(Approximate times)

• 00:00 Introduction to Joschua Knüppe and his work
• 09:51 Joschua’s experience as a scientific advisor for Netflix’s The Dinosaurs
• 19:56 The process of creating scientifically accurate dinosaur reconstructions
• 30:08 Challenges of communicating scientific uncertainty in media
• 39:57 The influence of fossil evidence and environmental data on paleoart
• 50:11 Future projects and research in paleoart and paleontology

Summary

In this episode, paleo artist Joschua Knüppe shares insights into paleo art, the process of creating scientifically accurate dinosaur reconstructions, and his role in Netflix’s The Dinosaurs. We explore how scientific knowledge influences media portrayals of prehistoric life and the importance of transparency in science communication.

Takeaways

• Joschua Knüppe’s role as a paleo artist and scientific advisor
• The process of creating scientifically accurate dinosaur reconstructions
• The influence of scientific literature and fossil evidence on paleoart
• Challenges of communicating scientific uncertainty in media
• The importance of transparency and honesty in science communication
• The impact of media portrayals on public understanding of dinosaurs
• The use of modern techniques and research in paleoart
• The role of color, behavior, and environment in dinosaur reconstructions
• The collaboration between scientists and artists in media productions
• Future projects and ongoing research in paleoart and paleontology

Keywords

paleontology, paleoart, dinosaur reconstruction, Netflix The Dinosaurs, scientific accuracy, science communication, fossil analysis, prehistoric animals, paleo artist, dinosaur media

Hello and welcome to I know Dino. Keep up with the latest dinosaur discoveries in science with us. I’m Gareth. And I’m Sabrina. And today in our 472nd episode, we’ve got a new dinosaur named Kank.

speaker-1 (00:42.69)
Yeah, it’s a fish-eating dinosaur. We also have an interview with Yoshua Kanupa, a paleo artist and scientific advisor who we’ve had on the show before. Plus, we’ve got Dinosaur of the Day, Ooko Tokia, an armored ankylosaur. And our fun fact, which is that T-Rex is now the most valuable dinosaur fossil. It dethroned Stegosaurus.

speaker-0 (01:06.038)
Mm-hmm. ‘Cause there was that one Stegosaurus sold for a bunch of money. Yep.

speaker-1 (01:09.482)
Apex. We’ll get into it later.

speaker-0 (01:12.024)
I mean, it makes sense. T-Rex had always been the most expensive. It just took, I guess, for the next T-Rex to come up for sale for it to regain.

speaker-1 (01:20.204)
It was surprising to talk about stegosaurs being the most expensive.

speaker-0 (01:23.872)
Yeah. But before we get into all of that, of course, we’d like to thank some of our patrons for making our podcast a reality. And this week we have a new patron to thank, and that is Todd. Thank you very much, Todd, for joining our Patreon. And then rounding out our shout-outs, we’ve got Potta, Geraldine, Tiffany, Chris, Charybdis, Clever Girl, Mongol Warrior, Michael, and another Michael. Yes.

speaker-1 (01:49.006)
Two different Michaels.

Thank you so much for being a Dino at all and being part of our community. We hope you are enjoying being able to talk to each other on our Discord and getting our bonus content. If you want to become part of our community, then you can check us out at Patreon, patreon.com slash inodino, see if all the perks are things that you might want.

speaker-0 (02:14.808)
Hmm. And as of this release, there’s still a little bit of time to get a exclusive card through our backer kit in the extended what they call pre-sales period, confusingly, after the crowdfunding ends. And you can do that at inodino.com slash cards. And if you’re a patron, then you get access to the exclusive NanoTirana stuff.

speaker-1 (02:40.248)
Jumping into the news, we’ve got a new dinosaur, an uninloggiid, Kink Australis. This was published in the Journal of Vertebrate Paleontology by Mateus Jay Mata and others. And uninloggiids were bird-like theropods related to Velociraptor. Their fossils have been found in South America, Madagascar, Australia, Antarctica. There’s at least eight species of them.

This new one, Kank, lived in the Lake Cretaceous about 70 million years ago in what is now Patagonia Argentino, is found in the Churillo Formation. The fossils were first found in 2018, but they were too fragmentary to be named a species at the time. The holotype is a single vertebra, but eventually more specimens were found, and some fossils found include part of the feet, five shed teeth, and vertebrae.

speaker-0 (03:29.518)
Could be worse.

speaker-1 (03:31.842)
Well, at least it wasn’t named just on one bone. So Kank is medium sized, estimated to be about sixty pounds or twenty seven kilograms and up to ten feet or three meters long.

speaker-0 (03:34.402)
Yeah.

speaker-0 (03:45.09)
Medium sized, that sounds really small to me, but I guess for an Unan Lagiad it was medium sized.

speaker-1 (03:51.798)
It’s similar in size to a greater Raya.

speaker-0 (03:54.806)
Yeah, Rheas reasonably sized, I guess. Yeah. But they’re alive today. So Well. For a non avian dinosaur, it seems like any if anything alive today, any bird alive today is bigger than

speaker-1 (04:08.514)
think when whenever we talk about medium or large size or small size, it’s in regards to their closest relative.

speaker-0 (04:14.806)
It’s true. Yeah.

speaker-1 (04:17.166)
‘Cause sometimes we’ll talk about a small sauropod, and a small sauropod is bigger than a medium sized loggy.

speaker-0 (04:24.214)
Or bigger than like a vehicle. Yeah.

speaker-1 (04:26.702)
All right, so the genus named Kank is in honor of a myth of the Ayana Kank, the southernmost group of the indigenous Tewelche people of Patagonia. Kank refers to an old giant Rhea or Rhea whose powerful running steps left an imprint of its toes in the sky, and that formed the Southern Cross constellation. And the species name Australis means from the south, which makes sense. It’s a southern hemisphere dinosaur.

speaker-0 (04:55.704)
That’s interesting because I remember the native people from Broom, Australia, had their legend of a giant emu bottomed man who walked on the beach and made the basically like tyrannosaur or other large theropod-sized footprints. And this one has a rea, which is basically like an ostrich. But instead of walking in the sand, it’s walking in the sky. Yeah.

speaker-1 (05:22.19)
Birds get around. So Kank is smaller and more grassile compared to other Unanlagids like Ostroraptor. It did have that large claw on its second toes. That’s one of their features and why they’re somewhat closely related to Velociraptor. So maybe Kank was an active fisher. It had a long snout, a lot of teeth, and a long, flexible neck, which would be good for fishing, similar to modern herons.

speaker-0 (05:51.478)
least we assume it would ’cause we didn’t find any of those parts. All we have is f feet, teeth, and neck vertebrae. they’re neck vertebrae. Okay. Yeah.

speaker-1 (05:58.168)
Vertebrae.

speaker-1 (06:02.19)
It had pneumatic cervical vertebrae, so air sacs in the neck bones. And based on the neck bones, it had special structures for muscle attachment and to protect neck blood vessels, similar to today’s herons with the complex neck movements. It also had small teeth that were not serrated. So another thing going for going after fish. Yep. It lived in a wetland environment with a lot of rivers and streams. So this helps show that this group were fish eaters.

speaker-0 (06:31.448)
The Unan Lagiads, or at least some of them.

speaker-1 (06:34.06)
Yeah, and Kank was also found alongside fish fossils, so there’s a lot of things pointing to the fish here.

speaker-0 (06:39.95)
Yes. Which is still evidence, by the way. Still admissible. People think circumstantial evidence doesn’t count, but it does. well then. Just means that it’s the circumstances. Like being fossilized by a fish.

speaker-1 (06:54.254)
I mean, it’s possible kink went for other prey too, because there were frogs, lizards, turtles, and mammals that lived around the same time and place. But there’s a lot of clues pointing to the fish. Mm-hmm. It would have had to watch out for mape. That’s a big mega raptorid that lived around the same time and place. yeah. Yeah. Be careful. There’s plans to dig more in the same area where these fossils were found. Hopefully to find more kink fossils. So it’d be cool to learn more about this potential fish eater.

speaker-0 (07:20.322)
Get more than some teeth, some foot bones and some neck bones. Yeah. We could confirm that it actually does have that long snout that people are assuming it had. Hmm. And in just a moment we’ll get onto our interview with Yoshua Kanupa, but first we’re gonna pause for a quick sponsor break.

speaker-0 (09:22.614)
And now on to our interview with Yoshua Kanupa. But as always, we have an extended version of this interview. So if you’re a patron, you can check out your premium content feed and you will see it there, along with a little footnote at the bottom of the show notes in the extended interview that tells you when to skip ahead to for the ad-free episode if you want to skip over this slightly abridged version. We are joined this week by Yoshua Kanupa, who is a paleo artist and the host of PaleoStream on Twitch.

Which is great handle. Is also the scientific advisor for Netflix’s The Dinosaurs, which came out earlier this year. And if his name sounds familiar, we talked to him in episode 403 about his graphic novel Europosaurus, Life on Jurassic Islands, which we very much enjoyed and we like the conversation too. So we’re happy to talk to you again. Thank you for joining us.

speaker-2 (10:12.46)
Yes, thank you. Thank you for the invitation.

speaker-1 (10:15.064)
So, what’s it like to be a scientific advisor for something like a Netflix show?

speaker-2 (10:20.654)
It’s hard to describe because as it should be pointed out, my part in this was absolutely minuscule.

speaker-1 (10:28.27)
It was enough to get you credit though.

speaker-2 (10:32.48)
Yeah yeah, they they gave me credit, which I honestly did not expect at all. So I I I should explain a little bit how this this all went down. Netflix, the dinosaur, is basically a direct continuation of Netflix’s other paleo documentary, Life on Our Planet, which we usually just call Loop in the community. And after Loop came out, a few days afterwards, Tom Fletcher, the main consultant.

of that show actually joined our Discord server. We didn’t even invite him or anything, but he came in, he he answered a lot of questions and so on. I protected him a little bit from the little nerds and stuff. And we had a really nice conversation about the show. And like I tried to give like really constructive criticism to to the Wolves thing. And sometime later

He approached me in direct messages, like, hey, could we have like a little talk about this and like go a little bit more into the nitty-gritty of your ideas? Like what could make this program better? And I think we sat down for like two hours or so, and I had a long list of points where I think, like, okay, this this I think you did really well. This could be better. This part here, please don’t do it again.

speaker-1 (11:57.292)
Yeah.

speaker-2 (11:58.484)
If you ever pick this up again. And yeah, I didn’t really think much about it at that point, although I he already told me that yeah, we want to work more in this direction. And yeah, that was basically my part. It wasn’t really like for the dinosaurs, it was more like for life on our planet in a way. But as I was told, my critique certainly was hurt and was.

speaker-0 (12:21.166)
Interesting.

speaker-2 (12:28.096)
incorporated. Like one of my main critiques and quite a few other people, like I I was basically a little bit the voice of the paleo community going back to Netflix in in this situation. And what many of us critiqued was that individual interactions oftentimes broken down to more violent struggles like like fights and and hunting scenes.

We’re basically stand-ins for like greater evolutionary narratives, which is just not what happens. Yeah. Like how animals like interact violently is oftentimes not like deciding the evolutionary fate of a who’s lineage.

speaker-0 (13:17.364)
Mm. Yeah. It’s not like this one’s stronger and therefore it survives.

speaker-2 (13:21.71)
This one has the brains, you know, like like and when Spinosaurus steps into water, it gets a a twenty percent melee damage buff. And that’s why it like can now overpower Kakarodontosaurus, you know. It’s it’s it was a little bit at times a little bit like like a video game in its logic or in its storytelling. Yeah. And I think they really, really improved in in that regard, with the dinosaurs. So yes, that was my part.

on the wall thing. And and we we should also mention there’s many, many, many, many more consultants on this show. Like the only reason I really stick out because I don’t have a doctor or professor title to my name. But yeah.

speaker-1 (14:05.614)
Well was thinking ’cause we know you’re a dinosaur expert. There’s there’s a lot of experts, but experts in different aspects.

speaker-2 (14:12.876)
Yeah, yeah. You you could say I’m I’m an expert to a certain degree on like how these animals might have looked. Although that again, like to only to a degree. I I try to be like a little bit of an expert in everything in this. Like paleontology is such a huge field.

speaker-0 (14:30.158)
yeah. Definitely. Did you give any feedback on how they looked, like what you liked and didn’t like from Loop?

speaker-2 (14:36.224)
A little bit, although that really wasn’t my focus. Because I think like I’m talking to Tom Fletcher, he’s paleontologist, he knows the shortcomings largely himself. I know from other people who worked with like Big Studios before that there’s always something being lost in translation. Like like I think it’s one of the biggest problems of like the the overall creative process with Big Studios that you have this this hierarchy.

Like the the the consultant usually cannot directly talk to the artists themselves. It always goes through producer and like art director and then trickles slowly down to to the artist. so it takes longer and less less precise and and it’s just just unwieldy the whole process compared to what you would need to really make it make it work for something like this.

speaker-0 (15:34.742)
That makes sense why so many of these documentaries end up looking kind of similar because they they have the starting point and it’s easy to say, well, this one did a pretty good job and then the artists know where to start from there. And if they’re not talking through a new concept directly with someone with a lot of new input, it’s yeah, it’s not gonna change too much.

speaker-2 (15:54.798)
Yeah, and of course also these big studios, usually all the artists working there or like the companies they they hire, like these are not dinosaur experts. Like they might have never done a prehistoric animal before. And even if it might have not been for a docum documentary, like paleo documentaries with a lot of CGI are such a niche thing. Yeah. So yeah. I I mean I I there’s always hope that we get a little bit more now.

But yeah, it’s it’s certainly not the the usual thing for for these CGI artists to do that are more used to like doing doing like Marvel movies and Jurassic Park or Jurassic World at best.

speaker-0 (16:37.804)
Yeah. Yeah, that’s true. For every dinosaur documentary, there’s probably five or ten dinosaur fighting, you know, scenes in various movies or things that look kinda like a dinosaur that people would draw from.

speaker-1 (16:52.846)
It sounds like they took a lot of good feedback though because I know they made like Tyrannosaurus seem more parental. That’s something we don’t we’re starting to see a little bit more of in dinosaur media, but it’s still pretty rare.

speaker-2 (17:04.977)
Yeah. No, I I I really liked many things they they did with this season, the the things they showed. There’s there’s so many more interesting behaviors and setups they introduce. And I I I think my one of my favorite parts is that they actually have like the first episode being fully on the Triassic. Yeah. And and even starting before we have proper dinosaurs, like like showing like the setup.

Okay, here we have the animals that would eventually lead to to dinosaurs. That is so rare to have. And I’m I know many, many people also were, for example, very disheartened by the lack of Triassic stuff, for example, in the new working with dinosaurs. Which has different reasons why that didn’t happen, but it’s it’s yeah, pe people still want to see this this stuff, even if we don’t have the

Giant therapods, giant sauropods and stuff. Not the not the weirdest things. Yeah, I I think the Triassic and early Jurassic segments might have actually been my my favorite in the dinosaur.

speaker-0 (18:15.448)
Yeah, ’cause even though I mean I really liked the Seam of Spinosaurus because it was sort of a modern take and they were they showed it like just getting completely outswum by a shark. It’s like that was in loop, not in the dinosaurs? I think I saw it in the dinosaurs too. But the

speaker-1 (18:25.853)
That was in loop.

speaker-2 (18:32.984)
Yeah.

speaker-0 (18:36.81)
Yeah. It’s just kind of a fun to see, you know, these modern interpretations of Cretaceous stuff. But it’s also yeah, I I agree with you. My biggest thing with prehistoric planet on Apple was it was cool, but it’s like it’s the Hell Creek. And then when they did prehistoric planet too, it was like more of the Hell Creek mostly. And I’m like, you know, there’s so much more of the Mesozoic to go through. And with the Triassic, too, like you were saying, there’s lots of interesting stuff there that isn’t dinosaurs. So if you’re not just limiting

If sure, if you limit just strictly to true dinosaurs, like within Dinosauria, and you’re not showing any other animals, yeah, the Triassic is kind of boring. But if you look at the Triassic and you’re looking at all the fauna there, it’s crazy. Like the n the variety all and the story too of how it leads to the true dinosaurs after the Triassic Jurassic boundary is really interesting to see the comparison. Like, well, why did the dinosaurs do better than these other animals that superficially look really similar or look

Like you were saying, you know, if you had like a video game buff, like why would a pseudo Sukian that’s huge and almost looks like a T Rex in some ways with big teeth and a big impressive mouth? Like, how could that go extinct? But this little goofy, two legged, skinny coelophysoid is doing great. It’s a it’s a really interesting story.

speaker-2 (19:56.31)
Yeah, yeah, no, no. I I there’s there’s so much cool cool stuff happening in the Triassic. Like yeah, there’s there’s nature itself like reinventing itself like several times over after the big extinction at the end of the Permian. but also like the the Triassic is f long. There’s there’s so much still happening there. one of the I like like like I I was I was pointing

happily at the screen when when it came up on on the dinosaurs they actually name drop the carnian pluvial event. Like I think that might be the first time something is like this has happened in in like a big modern documentary. Like I sure there there are smaller on on the side that are mostly like fossils and talking heads and so on. And I think they are actually very important. But like

these really big budget documentaries usually shy away from stuff like that. I mean that was one of the biggest critiques of prehistoric planet ice age how little they went into these scientific terminologies. Yeah. And and stuff like that. I mean there I I think there are other things in in terms of like science communication that are really, really good in Ice Age. Like each episode basically going into like

one of the phases or one of the aspects of like these glacial cycles, like the freezing, the melting, and and what that does to ecosystems. So I really appreciated that, but at the same time you’re also a little bit a little bit left hanging wanting to know more, because many of these creatures you don’t even have a name to. Yeah. So yeah, I I I think say the dinosaurs does does this really well.

speaker-0 (21:45.826)
Yeah, that’s true. It’s it’s always a fine line of like how much narration, how much explanation is there, because you don’t want to make it like you were saying, just a pure talking head, almost like a lecture. But you also need to add enough information that when you’re done watching it, you weren’t like, well, I saw this big bird thing attack this saber-toothed tiger.

speaker-2 (22:05.614)
Yeah, yeah, of course. it’s always like, but who even remembers that or who even wants to know? But there is always people who will remember and who will want to know. And like even if they are not like wanting to go into paleontology and stuff like that, like there’s there’s there’s like studies on like while kids like dinosaurs and learning all these complicated names, that is a big part of that.

Like like it’s subtle it’s like an a pool of knowledge that kids can accumulate that they suddenly have that the the adults don’t have. And and it’s so important for that. So like them being like, no, we want to create this this cool product for the wool family. So we shouldn’t make it too technical.

speaker-0 (22:55.747)
Yeah.

speaker-1 (22:57.25)
The adults wanna know too.

speaker-2 (22:58.74)
Yeah, true. Adults want to know too and it’s it’s it feels like profoundly anti intellectual the world notion. Which is his own can of worms.

speaker-0 (23:08.588)
Yep, that’s true.

I can’t remember with Ice Age if they did I really like one of the things I really liked in Prehistoric Planet was the first Prehistoric Planet was they at the end of the episode, I know they did in the second one too, they would spend a few minutes sort of going back and explaining how we knew those things and sort of getting some of the scientific nomenclature out there sometimes. But I don’t remember seeing that in Ice Age, but maybe I just

speaker-2 (23:33.678)
They did that too. They did it actually in all three epis seasons, but in the first season these segments were separate from the actual program, and you could just click on that separately on Apple’s website, while in the second season it was part of the runtime, which many people liked a lot more. and many people wanted to see more of.

speaker-0 (23:58.38)
Yeah, I was gonna say the ratio to me, I could have used more of that end piece because I remember when we were talking, I got to interview one of the producers for Ice Age, and I had like a long list of questions, like, was this real? Was this real? Was this real? You know, like what was this based on? What was this based on? But I only had a couple minutes to talk to him. So I got through like two of them, but I still didn’t find out like

This behavioral thing they showed, is that just because we know that a modern bear did something similar, or is there actually something in the fossil record that shows it? And that’s the kind of detail. It’s hard to get that information without talking to someone who worked on the show because it’s it might be buried in some paper somewhere, but figuring out how much of it is inference versus how much of it was scientifically informed and from where is super valuable information. Like you said, I think a lot of people would be interested in.

Hearing just, you know, like, yeah, this part isn’t so well backed by science, but we think it’s fun and it could happen versus like, no, there’s a fossil that like really shows this was a likely thing. Well

speaker-1 (25:00.918)
I say like on Netflix is the dinosaur, they had the singing and Kylosaur, and that was based on that paper that that we talked about on our show.

speaker-0 (25:07.372)
Fossilized hyoid bone.

speaker-2 (25:09.462)
yeah, yeah, yeah, the the Lyrynx. Yeah, potentially lyrics. Like I I a friend of mine who is like he’s working in Tepholymy, but he’s like kind of like a little bit like like a paleovocalization nerd on the side. He he’s a little bit skeptical about that. But yeah, I know there’s there’s there’s cool cool things happening in in that department, and that we even have like these big osophite hyoids like in in ankylosaurus, like in in several

speaker-0 (25:12.216)
Mm. Yeah.

speaker-2 (25:38.776)
generalizing at this point. Like we I I think makes it very likely that they would do quite a bit of vocalization. Also with with like their very complex nasal passages. Not necessarily like in as in the dinosaurs with the pyloroplitis that they have there. Unfortunately not name dropped. But like in prehistoric planet Tartia

in in Mongolia. There we have or also like some some North American ones like you Procephalus. You have like incredibly complex nasal pastures, also like nasal openings that look really weird and that make you think, okay, what noises would come out of that? Because they they are like speculating, this is maybe for cooling the breast and stuff like that, because they are like in like desert environments or like like like getting the moisture out of out of there before it’s like exhaled and and stuff. But

That would do more than just like help with thermoregulation.

speaker-0 (26:38.478)
Yeah. Yeah. And even if that it evolved primarily for something like that, it doesn’t mean it affected the way they sound.

speaker-2 (26:45.238)
Yeah, yeah, also because we have stuff like this not just in the desert species, but also in like the much more humid North American parts.

speaker-0 (26:53.676)
Yeah. So yeah, it’s hard to say chicken or egg, like what it evolved originally for, but it could be that once they had it in that desert environment, nobody else was gonna drop it because all of a sudden they can make these cool sounds that really impressed the the ladies or the fellas, as the case may be.

speaker-2 (27:11.178)
Yeah, yeah, yeah. I mean I to to go back to what you said earlier with with like these segments at the end of prehistoric planet like showing off like how do we know some things and stuff like that. I I I like that. It was too little, absolutely. Like like every segment I feel like should have had something like this. Yeah. Like I would like to know more about the Namact and and why you show Dino Kyrus this way, yada yada yada.

Yes. But I think that’s in general like one of the biggest weakness of most paleo documentaries, even the ones that don’t do not have like a huge CGI budget, and that is academic honesty and transparency. Like not just saying this is how we know it, but also saying this is what we don’t know and this is what we can only speculate about.

speaker-0 (28:06.636)
Yeah, yeah, that level of certainty.

speaker-2 (28:08.98)
Yeah, like I I wa I was part of an little documentary two no three years ago at this point. And we filmed like a longer interview for like I I think the world shoot was like like six hours or so. Like with with me like talking to the camera but also painting live and stuff like that like that. In the end, nothing of that got into the documentary. Mostly because on the cutting floor.

They decided to change the tra trajectory of the wool thing because the format was supposed to be more about the facts, the hard facts, you know, the stuff we know. And we and and me and the director, we were talking mostly about all the things we don’t know and all the uncertainties and and so on. Like really going into okay, yes, we know all of this stuff, but there’s so much more we have no idea about. And

Like the director too had like a different idea about how it how how the wool program could be, and then the higher ups were like no no no no no, not all this this wibbly wobbly stuff. No, we want to give the people like the hard facts they can bring up at dinner parties, you know? Did you know that about dinosaurs? Yada yada yada. And and yeah, it’s it’s it’s basically sucking a little bit the the humanity out of the field in a

speaker-0 (29:36.16)
scientific method in general because it’s it isn’t just like a list of facts.

speaker-2 (29:40.736)
It’s it’s baffling to me sometimes what is all shown to people and like sold as a truth, although we don’t know it. And I mean, I as a paleo artist that that is basically my bread and butter. I I sell illusions to people, like illusions of certainty. I don’t know if T-Rex really looked like this, but it looks plausible and it follows like

the scientific literature to a degree, but at some points the literature just stops and you’re left with a oftentimes huge gaping hole that you have to fill with creativity. Yeah. And that is just not accessible to most people.

speaker-0 (30:25.922)
Yeah. I think of that with with kids that I talk to. Sometimes they’ve got their favorite dinosaur. And sometimes the reason it’s their favorite is because a toy has painted a specific color or they did like a specific sort of interpretation on little spines it might have had on its back or some little detail. And you know, you don’t want to crush their spirits by saying, like, well, maybe they all had that, or maybe none of them had that, or that color might be wrong, or something like that.

But it’s interesting, you never know what people are going to latch on to that maybe to a paleo enthusiast might be obvious, like, we don’t know the exact good to acknowledge that in these sort of documentaries to be like, Well, we made them this color because we took inspiration from this bird, but that’s really where it starts and ends.

speaker-2 (31:02.51)
No absolutely.

speaker-2 (31:12.802)
Yeah, no, like there’s the yeah, the the emotional attachment that people form to certain ways of how we portray the past or individual animals is is so strong sometimes. I oftentimes do it the other way around when I to talk to small children. I absolutely crush their dreams right there. I’m I’m like

Brazer do it early than later when when their attachment has grown even deeper and they can no longer because then you get like like angry little people in the comments being like, why does it look like this? It should be like this.

speaker-0 (31:48.184)
You’re shutting them down before they get online as the

speaker-2 (31:50.574)
Yeah, yeah, no, like I I got a relatively late little sister and I taught her very early on about stuff like that and she grew up fine. So

speaker-1 (32:05.39)
So it works.

speaker-0 (32:08.686)
Good to hear.

speaker-2 (32:09.442)
Yeah, yeah. No, like I I what what I like to say always is when it when it comes to my line of work, learn to love the process, not the illusions is it creates. That also helps a lot with stuff like I might create artwork the other day and like today something comes out that completely changes how we imagine something. And when I’m like too much attached to the way

things look the way I painted them, then I will never be happy.

speaker-0 (32:42.946)
Yeah. Mm-hmm. Yeah, that’s a very good point.

speaker-1 (32:45.676)
In those cases you’re okay just start over.

speaker-2 (32:48.258)
Yeah, no, I’m I’m usually with with rare exceptions, I’m usually like, boy, more opportunity to do painting. You know? Like explore that once again. And I I think that is something that many, many people need to to learn that we oftentimes have to convince ourselves after new publications come out.

speaker-1 (32:56.351)
Yeah.

speaker-0 (32:58.337)
Like

speaker-2 (33:16.014)
To like something again because we are so used to aesthetics. We we oftentimes make arguments from aesthetics. The way something is portrayed can be just as important sometimes for the acceptance of science as the actual science itself. But I’m tasked to create an image of a new species.

One of the so first things I do is look in the section about geology and see okay what what else has been found here and what are the conditions, so the depositional environment, like how was this thing dep deposited here in this locality? And what does this tell us about the environment and so on? There there is so many information you can draw from that, even down to the coloration of the animal to a certain extent.

Because pigments found in the environment can travel up the food chain and will end up potentially in in your animal. Like like flamingos being pink because they eat all these little red crustaceans is like a famous example, but there are so many more where this is the case. And yeah, so that is always one of the first things to do.

speaker-0 (34:37.098)
I love that detail. Yeah. Thinking like, this animal might have been this color and it was in the same ecosystem as this other animal. So maybe eating it would change it its color.

speaker-2 (34:46.742)
Yeah, that that can have an influence, but also just like is it like an open environment or like a dense forest? Animals today like tend to have different patterns and gradients in their coloration based on what environment they they live in. And then it c goes to the like like you can like talk for hours just about coloration, but f another important thing is like does the animal see color or not?

speaker-1 (35:15.806)
Yeah.

speaker-2 (35:16.78)
And this is a constant question always with dinosaurs because yes, they fill all these niches that big mammals fill today, but mammals are largely colorblind, and dinosaurs were probably not, because crocodiles and birds see colors really well. Yeah, yeah, oftentimes better than us, like seeing into the ultraviolet spectrum, and so.

speaker-0 (35:35.052)
Yeah, maybe even better than us.

speaker-2 (35:46.73)
You have on the one hand that, but then again you also have to keep in mind that large animals, even non-mammals, usually get more blends the larger they get. So there’s a

A lot, a lot of discussion going on all the time in in regard to that. also in dinosaurs where we have soft tissue and and so on. Like there was the idea for a while that in heterosaurs we could see patterns in the scales because they were like larger and smaller scales, sometimes appearing like in clusters and stuff. So people were like, maybe the bigger like that means these scales.

Guys had spots and this guy over here had stripes and stuff like that. But when you look at modern day reptiles, usually scale size doesn’t really correlate with color. So another idea in the moment is that maybe this has a more like a functional thing going on here that the bigger scales are like more rigid parts of the skin, and the smaller scales are are the softer parts. So you have like integrated folding patterns.

That helps with the elasticity of of the skin and stuff. So super cool stuff.

speaker-0 (37:02.956)
Yeah. We did see. I remember Sabrina was recently talking about a paper where there was a sauropod and some of the pigmentation, and it looked to be that it had sort of a speckled pattern to it. And that’s something you don’t see because, like you were alluding to, larger animals tend to be more bland. And it seems like that is the primary way that paleo art takes it. They seem to take that as like the over because that’s what people are comfortable with. You see a T-Rex and it’s big and it’s sort of

brown or green, it feels right if you make it striped or you make it really bold colors with all sorts of, you know, variation on it. It doesn’t look like anything we’ve seen today. And it just seems and it also doesn’t look like famous depictions of it, I guess. then people might not have as good of a reaction to it. But I like the idea of like a Bronosaurus being colored like a giraffe or something. Just totally different than what you usually see. Yeah.

speaker-2 (37:59.502)
Giraffes are a weird case. And this is like going into color genetics and stuff like that, and and like how patterns are formed and and so on. It’s a it’s it’s very, very complex. I friend of mine is like a horse expert and he can like talk for hours about horse color genetics. It’s insane. Like whenever I do a horse, like I usually get like afterwards the comments, actually down there it wouldn’t be that tone because

Based on these and these genes, that is not really how it works. And if you have like a light lighter car part here, then you would also have lighter parts down here. Yeah. It’s really intricate. And the question then also is usually okay, okay, we know this about modern day horses, but how far in their evolution would that go back, these these things? And

speaker-0 (38:51.81)
Yeah, especially ’cause domestication has impacts on coloration too. And pretty much all the horses we have now are in a domestic I mean, there’s I think there’s a couple exceptions potentially, but most of them are on this domesticated lineage. So who knows how much that messed with their coloration.

speaker-2 (39:08.11)
Yeah, although apparently potentially not that much because we have this this cave art that actually shows some really interesting patterns and coloration that is similar to some modern day domesticated breeds. Where like for example, these these like very spotted horses, like that look a little bit like Dalmatian dogs. But stuff like this can also be found in cave art.

speaker-0 (39:23.379)
that’s awesome.

speaker-2 (39:37.6)
And like color genetics shows that genes for like this stuff appearing go back far enough that you would also have like spotted horses probably in in in prehistoric times. At least within the genus Equus.

speaker-0 (39:49.846)
That’s great. Yeah. It’s too bad we don’t have any cave art of dinosaur coloration. That’s true.

speaker-1 (39:52.782)
Mm-hmm.

speaker-2 (39:57.088)
That would make it so much easier. Then again though like like people back only a very limited palette to work with. I mean it’s it’s

speaker-0 (40:03.597)
Yeah.

speaker-1 (40:05.462)
It’s who knows how much creative liberties they would have taken.

speaker-0 (40:07.82)
Yeah, that’s true.

speaker-2 (40:08.706)
True, true that. Yeah. But yeah, like it’s it’s kind of a blessing that like most ice age mammals would probably have like a color palette that can be relatively easily reproduced with like ursin pigments yet that you find on your own doorstep. Yeah. You don’t have to like grind up laszuli to to get in br vibrant bruvaceri and stuff.

speaker-0 (40:32.747)
Yeah.

That’s a good point.

speaker-1 (40:36.782)
So since last we talk I mean, we you’ve mentioned a few projects that you’re working on, but I’m sure you’ve done many, many things because it’s been a few years, I think, since since we had you on the show. What are some of the projects you’re working on now that you can share?

speaker-2 (40:54.85)
One of the biggest things that is, at least from my side, already done is another graphic novel that should come out this year, probably in fall or a little bit later. It’s about an another locality. So with the Europosaur stuff, it was focused on the Langenberg query. And this one is about the Geiseltal open pit mine. Nowadays it’s a lake. but

No, it’s it’s an it’s an artificial lake. Many many of our open pit mines over here has been turned into into lakes, and it’s basically the eastern sister locality of Messel. Yeah. Similar preservation too, but it’s much less known, largely because it’s well, it’s eastern Germany, so for longest time it was like behind the Iron Curtain and stuff, and Messel so much more famous.

speaker-0 (41:32.952)
Nice.

speaker-2 (41:50.122)
and and so on despite the material from here being on par with with that what we what we have from Massel. And instead of Europosaurus our protagonist this time is a terrestrial crocodilian. Boveriucus which was like one of the apex predators of of this ecosystem.

speaker-0 (42:02.798)
Nice.

speaker-0 (42:09.582)
What’s the d estimated date of messel?

speaker-2 (42:13.022)
it’s it’s like fifty three million years.

speaker-0 (42:16.674)
Nice. So we’re getting some some more I w I wanna say modern, but that’s not the right

speaker-2 (42:23.906)
Yeah, Minozoic, it’s Eocene in age. So yeah, it’s it’s a little bit different environment from from Methel. it’s not like like like a lake where everything got stuck in it. it’s more like like a swamp in some cases, but also more open areas on so on. Like it it varies throughout the valley. There’s also a limestone plateau nearby where we have cave sediments. So we we know there were like

speaker-1 (42:24.216)
Yeah.

speaker-2 (42:52.962)
like actively forming caves in that region during the time of Bovariusuchis. And it’s it’s exact exciting and similar to the last graphic novel, this all goes hand in hand with a scientific project that also informs like what is like in the texts in the book. And yeah it it it brings a new new look basically to to this locality and hopefully gives gives it also some publicity because like everyone knows Messel.

speaker-1 (43:22.634)
Yeah. Yeah. Is that how you chose it? You wanna shine a light on a

speaker-2 (43:27.642)
It was one of the reasons. the other reason was that one of our authors already on the Europosaurus graphic novel, Oliver, he was curator at the collection for a while where all all the the Geiseltown material is housed. And and so it felt like a logical step after the Langenberg query to go into into this locality. And if it all goes well, there are ideas

For more of these kinds of books.

speaker-0 (43:58.541)
Nice.

speaker-1 (44:00.13)
I I I mean, we both really enjoyed your graphic novel. I like the style. It’s just something you don’t see too often. Yeah.

speaker-2 (44:07.468)
Yeah, yeah. Beyond that, there’s like a few other projects. I just recently finished another book about plesiosaurus, unfortunately only written in German.

speaker-1 (44:17.962)
speaker-0 (44:18.146)
We have some German listeners. What what’s the Plesiasor book called?

speaker-2 (44:22.35)
Title is The Welt der Plesiosaurier, Paläontologische Abenteuer, written by Achim Schwerman and Sven Sachs. Was an idea that has been like flown around in the heads of some people for a while. It’s mostly talking about like paleontology in general, like in the grand scheme of things, but plesiosaurus specifically.

With a specific focus then again on the plesiosaurs of Westphalia, which is my neck of the woods. Because there is an interesting amount of plesiosaurs we have here, four endemic genera so far. Among them the oldest plesiosaur from the Rassian, so the latest Triassic. Up

speaker-0 (45:13.006)
Nice.

speaker-2 (45:14.088)
Going then through through the early Jurassic. and we also have an early Cretaceous species here that is known from incredibly complete remains. I think it still is like the most complete Cretaceous plesiosaur of Europe. Bronchosaurus. Yeah. Known also from several specimens. Yeah, so it very important. All four have been coined fossil of the year.

speaker-0 (45:33.846)
Well.

speaker-0 (45:43.96)
my

speaker-2 (45:45.16)
recently, which is why this book was like published in a way in the first place, because okay, the idea was was around for a while, but then it became clear that this would happen, that we would get all four with basically awarded this title. And so Achim and Sven like, okay, now we have to put together a book. Now we have to make it happen. And I I did like probably over fifty

Illustrations for that for that book. Yeah.

speaker-1 (46:18.678)
That’s great. Do you know if it’ll be translated?

speaker-2 (46:21.762)
There is attempts in that direction. Like I I know Sven want and Achim want to to look into the possibility. I’m not sure if it might be too niche for for like English speaking publishers, but here’s open. Fingers crossed that it that it might work out.

speaker-1 (46:41.272)
Keep us posted and then for our German listeners, maybe check it out and let us know.

speaker-2 (46:46.39)
Yeah, yeah. for the German listeners, if you want to buy it, might be a little bit tricky in the moment because you will probably not find it on Amazon, but mostly through the museum where it’s published directly, the LVL Museum für Naturkunde in Münster. Unfortunately, the museum currently is being renovated, among other things, also their website. So they don’t have

the best online shop up and running in the moment. Of recording this might have already changed. I haven’t looked in while.

speaker-1 (47:18.062)
Maybe it’ll change.

speaker-1 (47:22.85)
Ha ha ha.

speaker-0 (47:23.754)
Also it makes it more fun. It’s like a scavenger hunt.

speaker-2 (47:27.542)
Yeah, yeah, yeah.

speaker-1 (47:30.39)
It’ll be worth it.

speaker-2 (47:32.704)
that is another big project in recent years. I did a lot of illustrations for the new exhibition they’re having there. Yeah, we my region here has has a lot of really cool localities and the new exhibition is putting a little bit more emphasis on that. Like we we have everything from like huge diversity of like Devonian fish and stuff like that, Triassic marine reptiles.

speaker-0 (47:40.078)
Nice.

speaker-2 (48:02.612)
As mentioned, like all these plesiosaurs, dinosaurs too, like Vien Venato are huge, megalosaur is is from from from here. Nice. And yeah, yeah. Also like Xenozoic stuff as like like big big proboscideons and tons of ice age stuff. So much ice age stuff that it’s it’s like getting too much for the local collections at the same time like like there’s a area in

The Rhinish Mountains, that is an basically the wool region is a former Devonian reef lifted up during the Mesozoic. we actually have their Cretaceous cave sediments in there with like like dinosaurs in caves preserved. Super rare, super cool stuff. Mostly like isolated bones and teeth, but like beautiful cut-through, like like a cross-section of the ecosystem. But most

speaker-0 (48:48.086)
Let’s see

speaker-2 (48:59.584)
Mostly what you find in there is like ice age megafauna. And that way too much. Like there’s still new caves being found to this day. And the people in Munster are usually the first people to be like contacted when something like this is found because they have to like go in there and like see if there’s any important fossils. And usually there is with like thousands of cave bears. Like

speaker-0 (49:26.434)
No cheese.

speaker-2 (49:28.427)
but also rhinos, mammoths and and and reindeer and there’s some megalosaurus and stuff laying around. There’s a lot. Yeah.

speaker-1 (49:40.588)
I guess that’s a good problem to have. Too much, not too little.

speaker-2 (49:43.318)
It is a good problem to ma have. What that is, I hope, something that will people take away from from the new exhibition, like just how much has been found on their own doorstep. Mm-hmm. Which is something I I love to like do in general, like like showing people like, hey, beyond the famous stuff in the US, you know, like beyond Hell Creek, there is so much more. Like oftentimes in your own neck of the woods that you you can explore.

artistically or or in terms of research. Over here in in set collection we have a bunch of fossils from the Cretaceous of beautifully preserved fish, like on par or even better preserved than what you see in Solenhofen. wow. Like like like little sharks with all the denticles and stuff like that. And

Really incredible stuff, like some of the earliest lantern fish are in there. And you can still see the bioluminescent organs in the skin. Nobody knows about the stuff. Mostly because the this the material is largely housed in a little local museum that mostly published about this locally, all in German and all nearly a hundred years ago.

speaker-0 (50:44.334)
That’s it.

speaker-0 (51:03.192)
That isn’t an issue for getting the word app.

speaker-2 (51:05.486)
Yeah. And and it it never ye really left left this this bubble because all the people who who like published on it were well pub publishing locally. And I guess in Germany you you might have known about this stuff. actually when you are in I think a Pittsburgh, you might have also known about this because at some point the museum traded a few specimens back and forth. but yeah, it’s very

speaker-1 (51:29.58)
Yeah.

speaker-2 (51:35.424)
unknown to to even fish workers, like people who study prehistoric fish. So whenever I see a fish worker, I’m like, have you ever heard of the fishes of Zendendor Zendenhorst? look at this, look at this. There’s a few images online and it’s like beautiful. But I want more people to work on this stuff because it’s it’s an absolute treasure trove for for research. There’s I think only one English speaking paper on this material.

speaker-1 (52:04.968)
I hope more people do work on it. Yeah. Maybe a graphic novel could come out.

speaker-0 (52:09.73)
Yeah.

speaker-2 (52:12.766)
They are I mean I I wouldn’t say no.

speaker-1 (52:14.958)
Cool. Well, so for our listeners, where is the best place if they wanted to find out more about you and your work online?

speaker-2 (52:23.8)
Simply Googling me usually works watching the tr the the streams on Twitch or now also YouTube. I’m I’m doing multi streams now. Yeah, yeah, yeah. simultaneously I I I got my app and finally got got a plug in for that. Because not everyone wants to join Twitch necessarily. But most people have a Google account so can join and comment on YouTube.

So yeah, no, that’s that’s why I’m doing doing stuff every every weekend. On Fridays, we have something called flocking together where people like vote beforehand on our Discord. like what’s what what do you want to draw? And the foremost voted on things is then will be done on stream by everyone who wants to join in, each one in 20 minutes. So it’s just sketches that come out of that. It’s basically just

little little drawing exercises. And every Saturday we do something called formation pieces, where we have a huge wheel of names with more than forty localities and formations on it. And we spin it every Saturday. And wherever it lands on, we take like two weeks to like research set locality or formation, and then within one sitting, sometimes two when it takes a little bit longer.

I do like like one piece showing like a panorama of set locality as it might have appeared when it was still a living, breathing ecosystem.

speaker-1 (53:57.71)
Cool. Well that sounds great. Especially if you’re an artist.

speaker-0 (54:02.008)
Mm-hmm.

speaker-2 (54:03.318)
It’s it’s a lot of fun. And I have to thank at this point like all all friends and and colleagues that that help with that. Like just keeping the like community running, but also helping with research research and stuff, because I usually don’t have the time to do that all myself, but there is very passionate friends that that some sometimes like very forcefully are like, Yeah, yeah, yeah, I’m I’m I’m looking into that. Go go go on.

speaker-1 (54:30.446)
It’s good. Well, thank you so much for taking the time to chat with us today. It was great to catch up.

speaker-0 (54:31.916)
Yeah.

speaker-2 (54:40.448)
It was a pleasure.

speaker-0 (54:42.616)
Thanks again, Yoshua, for taking your time to talk to us and explain all about.

speaker-1 (54:49.14)
art and streaming your art and your role in Netflix’s The Dinosaurus. Yeah, it’s always a pleasure to talk. So thank you.

speaker-0 (54:59.458)
And in just a moment we’ll get into our dinosaur of the day, but first one last break for our sponsors.

speaker-1 (56:07.534)
And now onto our dinosaur of the day, Ookotokia, which was a request from Tyrant King via our Patreon and Discord. So thank you. Ookotokia was an ankylosaur that lived in the Late Cretaceous and what’s now Montana in the US. It was found in the two medicine formation. It looked like a typical ankylosur. It was covered in armor, its body was low to the ground, it had that long tail with a club, a small head, it walked on all fours. It was large and heavy.

It’s estimated to grow up to sixteen feet or five meters long and weigh two point two short tons.

speaker-0 (56:40.494)
Compared to other ankylosaurs, I’d say that’s medium sized. We’re going on the family level of things. It’s way smaller than an ankylosaurus, for example.

speaker-1 (56:50.382)
Still heavy. The type and only species is O.O. Kotokia Horneri. It was named in 2013 by Paul Penkolsky. It was stored in the Museum of the Rockies for more than three decades, and then Penkolsky found it in the collections. The genus name means child of stone and refers to its body armor. And that name also honors the Blackfoot people. The fossils were found on their land.

So the name’s a combination of the Algonquin language spoken by the Blackfoot people and Latin. The species name, Hornerai, is in honor of Jack Horner who collected the type specimen. The holotype is a crushed but well-preserved skull, part of the shoulder blade, osteoderms, and armor on the neck, a large humerus or armbone, and other fragments. There were also six other specimens found that include parts of the skull, hips, arms, legs, shoulders, tail club.

And part of a cervical half ring. The skull of Ookotokia is relatively smooth compared to skulls of other ankylosaurs that lived around the same time. It had large eye sockets, and the back of the skull had some horn like protrusions. Mm-hmm. Things sticking out. It also had a large club at the end of the tail made of two big bone lumps. And maybe the club was for self defense, swinging at predators or rivals, or sexual selection. Ookotokia

speaker-0 (57:47.598)
Hey, not too bad.

speaker-1 (58:16.406)
Lived in an area that had a long, dry season and warm temperatures. Some other dinosaurs that lived around the same time and place include Ovarapterosaurs, the Nodosaur Edmontonia, Ceratopsians such as Brachyceratops, Trodontids like Troodon, Dramaosaurus such as Dramaeosaurus and Bambiraptor, and tyrannosaurids like Albertosaurus, Dyspleosaurus, and Gorgosaurus. And some other animals that lived around the same time and place include turtles, lizards, and gastropods.

speaker-0 (58:42.894)
It’s pretty fun name. I could see it being part of a song like O Koto Gia. It’s a lot of syllables too. For it’s not that long of a word, but it’s like every two letters gets a syllable. Yeah, it’s a good one. There are a lot of Algonquin names in the northern Midwest. The origins are like a lot of city names and stuff, and they’re always pleasant.

speaker-1 (58:50.368)
It is, it is.

speaker-1 (58:55.95)
It sounds nice.

speaker-1 (59:07.286)
And our fun fact is that T-Rex is now the most valuable dinosaur fossil. Again, a dethroned stegosaurus. So there was a T-Rex. Maybe you heard about this because it was all over the news. It sold at auction in July for 50.1 million US dollars. It was estimated to sell for like twenty to thirty million, so it went way higher than expected. Just for context, Apex the Stegosaurus sold for forty-four point six million US dollars in twenty twenty four. So

couple of years earlier.

speaker-0 (59:37.954)
The previous record holder and the the couple before that were both T Rex. I think maybe the most expensive T Rex was that one that ended up in Abu Dhabi. It was like thirty two million. Yeah, was that Stan? Yeah.

speaker-1 (59:49.39)
Stan. Stan. So this T-Rex was found in South Dakota, lived more than 67 million years ago, and it’s nicknamed Gus after the late Gary Gus Licking, a cattle rancher whose land it was found on. It took three years to excavate, or three field seasons to excavate Gus. They finished getting gus out of the ground in 2023. Then it took another three years to reconstruct the T-Rex, and it’s one of the largest T-Rex found.

It’s about twelve and a half feet or three point eight meters tall. It’s about thirty eight feet long. Its skull is about fifty four inches long. Yeah. And the skull’s too large and heavy to be mounted on the skeleton, so they mounted it with a reproduction of the skull.

speaker-0 (01:00:26.606)
That’s big.

speaker-0 (01:00:33.538)
Yeah, that’s pretty standard. Mm-hmm.

speaker-1 (01:00:35.916)
Now Gus is about sixty one percent complete by bone count. It had thirty out of thirty two belly ribs or gastralia, which is pretty good, and a hundred and eighty three fossil bone elements.

speaker-0 (01:00:47.35)
This makes me guess that some of the bigger bones were missing. Cause if they have the bigger bone, they’ll do the completeness based on the volume of the bone and be like, Yeah, it’s missing the thirty whatever gastralia, but those barely count because they’re so small. But in this case, since they’re counting up all the gastralia, I feel like they must have been missing some of the big stuff.

speaker-1 (01:01:07.32)
I didn’t see any illustrations or anything, so I don’t know which bones they are, but I think the gastralia was highlighted because we don’t find it that often. Yeah. It’s possible Gus fought other T Rex because there’s a bite mark on top of its skull. There’s also broken ribs and other signs of injuries. And Gus was sold over the phone. There was a I think a just a few minutes bidding war and then it went for fifty million US dollars. So a lot of paleontologists in museums are not happy because, you know.

speaker-0 (01:01:16.462)
For sure.

speaker-1 (01:01:37.122)
Gus can’t be studied now, and they were priced out because the bidding started at nineteen million US dollars, and then of course went way above that.

speaker-0 (01:01:45.998)
You didn’t say who bought it, is it an anonymous buyer, I assume?

speaker-1 (01:01:49.986)
We don’t know. It was somebody bought it over the phone.

speaker-0 (01:01:53.142)
Okay. So sounds anonymous then. I mean, every once in a while, actually not even that infrequently, these do end up in museums, whether they’re purely donated or there’s some sort of agreement where they’re on display, whether or not, like you said, anybody’s gonna research it under those conditions is sort of a separate question. But hopefully it ends up in some public display of one sort or another and not just in somebody’s home. Yeah. I guess time will tell.

speaker-1 (01:02:22.264)
Yeah, we’ll see. I’m sure we’ll hear about it if that’s the case. Hopefully. And that wraps up this episode of I know Dino. Thank you so much for listening. Stay tuned in our next episode of I know Dino in a couple weeks. We’re gonna be talking about so many new sauropods. I think I counted eight we need to cover at least. Yeah. So many new dinosaurs to catch up on.

speaker-0 (01:02:41.335)
my That is a lot of sauropods.

Well certainly not me.

speaker-2 (01:02:48.782)
Okay.

speaker-1 (01:02:48.856)
Who? Who would say that?

speaker-1 (01:02:53.678)
And if you’re looking for more paleo goodness in the meantime, in between our episodes of Ino Dino, we’ll be having our next Ino Paleo episode, number forty two. We’re gonna be celebrating the number forty two in Hitchhiker’s Guide to the Galaxy, partly by talking about forty two fish, yes.

speaker-0 (01:03:19.916)
That’s a lot of fish. Yeah. And not just forty two like fish, forty two different species of fish.

speaker-1 (01:03:25.952)
Yes. Well genera.

speaker-0 (01:03:28.106)
That’s even more.

speaker-1 (01:03:29.71)
Yeah, so if you want to hear that episode or other bonus content, head over to patreon.com slash inodino. Thanks again, and until next time.

(Approximate times)

• 00:00 Introduction to Dinosaur Growth and Size Estimates
• 03:06 Discovery of Dasosaurus in Brazil
• 07:48 Largest Dinosaurs and Their Size Estimates
• 14:39 Models and Variability in Dinosaur Growth
• 28:41 Early Growth Strategies of Archosauromorphs
• 31:32 Scale Growth and Function in Dinosaurs
• 34:38 Parental Care in Dinosaur Reproduction
• 39:14 New Findings on Tyrannosaurus Rex Growth
• 46:28 Growth in Sauropodomorphs and Titanosaurs
• 55:42 Growth and Diet Changes in Sauropods
• 01:03:24 Dinosaur of the Day: Tomba Titanis
• 01:05:42 Why Birds Lay Large Eggs and Brain Size
• 01:08:00 Implications of Brain Size on Dinosaur Reproduction

Summary 

This episode explores dinosaur growth, size, and parental care, featuring recent discoveries and research on various dinosaur species and their development patterns. 

Takeaways

• Dinosaur growth and size estimates 
• Bone histology and growth rings 
• Impact of climate on dinosaur size 
• Parental care strategies in dinosaurs 
• New fossil discoveries and their implications 
• Growth rates of tyrannosaurs and sauropods 
• Bone remodeling and soft tissue estimates 
• Sexual dimorphism and growth variation 
• Egg size and brain size correlation sound bites

Keywords

dinosaurs, growth, size, parental care, sauropods, theropods, paleontology, fossil record, dinosaur evolution 

Hello and welcome to I know Dino. Keep up with the latest dinosaur discoveries and science with us. I’m Garrett And I’m Sabrina. and today in our five hundred and seventy-first episode

speaker-1 (00:37.708)
We’re talking all about dinosaur growth. plus a new titanosaurform. They sure did. Yeah, specifically Dassosaurus, which got pretty large. It lived in what’s now Brazil. And yeah, the rest of the episode is dedicated to dinosaur growth, which includes news about Tyrannosaurus hatchlings, how there were so many, and they were pretty small, how tyrannosaurus took 40 years to reach full size. Some dinosaurs grew really fast, some were incredibly slow.

speaker-0 (00:42.562)
They grew a lot.

speaker-1 (01:07.02)
And we talk about how growth affects how much dinosaurs need parental care. We also have a listener question about how sauropod diets changed as they grew, and a whole lot more. Plus, of course, our dinosaur of the day, Tamba Titanis, which was a titanosaur form from Japan. And our fun fact, which is that birds may lay large eggs because of their brain sizes, because it turns out growth is connected to so many things. Yes.

speaker-0 (01:33.536)
Interesting. But before we get into all that, as always, we’d like to thank some of our patrons and we have ten new patrons to thank this week. We have Joseph, Maggie, Julia and Piney, Alicia, Spino Dino, Brad, Gregol Sower, Tectonic Stego, Aloys, and Ben.

speaker-1 (01:40.364)
Amazing.

speaker-1 (01:55.022)
Thank you so much for joining and being part of our community, being a dino it all.

speaker-0 (02:00.098)
Yeah, we have at least one more new patron to thank next week, maybe more. Who knows what’ll happen by then. Yes. And some people I think might have joined to get the exclusive nano tyrannus card and sticker in our backer kit campaign, which I believe we’re doing a little bit of a encore of for one month. We’re not going for stretch goals anymore, but if you want to get the Shri Rapac that was unlocked.

As well as the other five or six cards. If you’re a patron, you can do that at inodino.com slash cards. And thank you to all of our patrons.

speaker-1 (02:36.654)
Thank you, yes, for our Patreon and for the backer kid support. It’s really cool that we were able to bring these dinosaur trading cards to life. All right. So jumping in, I’m going to start with the new dinosaur, the new Titanosaurform dinosaur, Dasosaurus tocontinensis. And I want to thank Tito Aureliano, who’s one of the co-authors, for sharing this one with us. This was published in the Journal of Systematic Paleontology by Elvermeyer and others.

And it was a fairly large sauropod. It walked on all fours. It had a long neck, a long tail, the small head. Well, it was more like medium to large in size. It’s estimated to be about sixty six feet or twenty meters long.

speaker-0 (03:18.51)
That is big, but not that big for a titanosaur or I guess I should say titanosaur form.

speaker-1 (03:23.928)
Yes. It does look similar to another Titanosaur form, Garumba Titan. That one lived in the early Cretaceous in what is now Spain. This one, Dassosaurus, lived in the early Cretaceous in what is now northeastern Brazil in Maranjao. It was found in the Itapacuru Formation. And some other animals found there include the Rhubaki saurid sauropod, Amazonsaurus, indeterminate theropods of spinosaurs and carcarodontosaurs.

As well crocodilomorphs, mosasaurs, plesiosaurs, turtles, and fish. So lived in this warm, semi-arid climate that had seasons.

speaker-0 (04:00.174)
So probably pretty similar to what Spain was like back then, because back in the early Cretaceous, Africa and South America were still connected, and Europe was always even back then close to Africa. Mm-hmm. So it wouldn’t have been too far away. So I guess it’s not too surprising that they’re similar.

speaker-1 (04:17.934)
Yeah, and Dacesaurus is part of Samphospondyli. That’s a clade of titanosauriform sauropods, so not Titanosaurs, but Titanosauroforms that lived in the late Jurassic to Late Cretaceous. They’ve been found on all continents and they have at least fifteen tailbones.

speaker-0 (04:34.542)
Fifteen is very low. Yeah.

speaker-1 (04:37.176)
Yeah. But Titanosaurs I think and Titanosaur forms tend to have shorter tails.

speaker-0 (04:42.095)
you’re right. Yeah, ’cause there a lot of are more of like a brachiosaurus type body plan with a big neck but not so much on the tail. Yeah.

speaker-1 (04:49.44)
Yeah, not like Diplodocus that has very long tail. So Dacosaurus has a mix of features that we see in early diverging sauropods as well as later titanosaurs. So earlier and later sauropods, such as the growth pattern that you see in its bones, how fast certain bones remodel. See, we we are talking about growth. Titanosaurs have the highest known rates of bone recycling, where they replace and repair their bone. It’s also known as bone remodeling.

The fossils of Dastosaurus were found on a slope that was about 26 feet or 8 meters high. They’re found in 2021 during construction of a railway, and they’re more than 100 million years old, early Cretaceous. It’s known as the dinosaur of Davinoopolis, before it was officially named, because that’s the municipality in the state of Brazil where it was found. The fossils found include ribs, parts of the hands and feet, parts of the arms, parts of the legs, parts of the hips, and at least 10 tailbones.

speaker-0 (05:46.222)
Pretty good. Yeah. No head though.

speaker-1 (05:47.778)
Head. That’s okay. We’ll take what we can get. The name Dasusaurus means forest lizard. It refers to where the fossils were found, which is an area that has most of the Amazon rainforest. And the species name Tocantinensis is after Tocantins, which is a major South American river and the name of the administrative region of the state where the fossils were found, near the eastern banks for the Tocantins River.

Now when talking about dinosaur growth, there’s two terms that come up a lot. The first is lines of arrested growth or lags, and those are the tree like ring bands that you see in the bones when you slice them open or slice off pieces.

speaker-0 (06:29.538)
Slice it really thin pieces. Yes. Known as histology.

speaker-1 (06:33.72)
Yeah, and they help you estimate the age of the animal because they leave a mark when growth slows down or pauses. And often that happens when there’s fewer resources, like in winter. So you can estimate all right, three lags, that’s at least three winters it’s been through. Mm-hmm. The other term that comes up a lot is bone remodeling, which we already talked a little bit about with the new titanosaur form. And it’s basically you’re replacing old and damaged bone with new bone.

And it helps to keep bones strong and repair micro fractures.

speaker-0 (07:05.218)
Yeah, it also just happens as animals age because those tiny little baby bones need to grow up into bigger bones and the structure is a little bit different. So they get remodeled as the animal gets bigger and heavier.

speaker-1 (07:18.67)
Yeah, it also happens when even when the animal is small and putting a lot of stress on the bones, like walking around. So growth ends when you reach your adult size, but just how big could dinosaurs get? We’ll do a quick recap because we had an episode 486 called How Dinosaurs Got So Big. And I thought it’d be fun to talk about the biggest ones. Mm-hmm. So the longest, heaviest, and overall largest dinosaurs were, of course, the sauropods. The biggest one of all time may have been

Mara Punisaurus, originally thought to be Amphoselius. And that one, the estimates range all the way up to like a hundred and ninety feet or fifty eight meters long and weighing a hundred and fifty metric tons or a hundred and seventy short tons. We get into more details in the episode, but I just wanted to give you the biggest estimate because that’s impressive.

speaker-0 (08:06.336)
Yeah, but that’s not really the size we thought it was anymore. Yeah. Those were sort of the outlandish early estimates.

speaker-1 (08:14.904)
That’s true. And then it it might not have even been the heaviest dinosaur because there’s Bruhathkyosaurus, which is there’s one estimate from twenty twenty three that said it could get up to a hundred and ninety tons, which would be crazy.

speaker-0 (08:31.234)
Yeah, again that’s the that’s the very upper edge of the estimate, like the farthest error bar out.

speaker-1 (08:37.665)
Yeah. And then of course, sauropods aren’t the only dinosaurs that got big, although they got the biggest. There were some large theropods like Spinosaurus. One was estimated to be up to fifty nine feet or eighteen meters long, which is a good size.

speaker-0 (08:54.316)
Very long for a theropod, that’s for sure. Yeah.

speaker-1 (08:57.282)
And then of course Tyrannosaurus could get pretty long. The largest estimates are for up to 40 feet or over 12 meters long. You get into ornithopods, we’ve got Shantungosaurus. That’s a large saurolophine hadrosaur or duckbill, but that didn’t have a crest. And that one was estimated to be up to 54 feet or over 16 meters long.

speaker-0 (09:20.184)
Oof. Yeah, and they were pretty bulky too.

speaker-1 (09:23.16)
Yeah. And it could weigh up to sixteen metric tons or eighteen short tons. So we know about some of these really big dinosaurs. It’s unlikely though that we’ll know how large the biggest of the biggest got. Just don’t know what we don’t know. But for some comparisons, the biggest mammal is the blue whale. That’s about ninety eight feet or thirty meters long. So smaller than some of the sauropod estimates.

It weighs a lot, of course, a hundred and sixty tons or a hundred and forty five metric tons.

speaker-0 (09:53.678)
Probably heavier than any of those dinosaurs. Some of those really upper estimates were above a hundred and fifty tons. Yeah. But really, usually when we’re talking about sauropods, the weight estimate is more in the like high tens of tons, you know, like sixty, maybe eighty tons. Yes. I don’t think there are any where people are confident that they were over a hundred tons.

speaker-1 (10:18.434)
Yeah. But they were still really heavy compared to like one of the largest land mammals that we know about is this giant hornless rhino that’s estimated to be sixteen and a half tons. Fifteen metric tons, which is just so much smaller than some of these dinosaurs.

speaker-0 (10:34.801)
yeah, that paracerathurium. Mm-hmm.

speaker-1 (10:37.774)
So how is it that dinosaurs could get so large? Well, there’s a few factors probably. They laid eggs, so they could start out pretty small as hatchlings and then grow. But mammals, we grow our babies in our bodies, so that puts some size limitations on mammals, slash us. And souriskians, which include theropods and sauropods, they had those bird-like respiratory systems, so they had the lighter bones, the air sacs to stay light.

speaker-0 (10:54.68)
Yeah.

speaker-1 (11:04.258)
They efficiently inhaled oxygen. They had those bird-like lungs, so they could continuously take in the oxygen. And this helped, well, this allowed them to get big. And why did they have these things? Well, it could have been so they could be better at eating more food or a defense mechanism. Was it really an advantage to get so big? Because big animals tend to go extinct during major extinction events. And of course the non-avian dinosaurs did, but it probably was an advantage for a while.

speaker-0 (11:29.154)
Yeah, it’s really a fascinating question of why they got so big, because we don’t really know for sure. I think the best guesses are a combination of things. They were able to do it because they had that amazing respiratory system. Certainly the super long neck probably wouldn’t be possible without that breathing system and the sauropods. Yeah. And also with the long neck, like you were saying, the lightened bones allows them to get so big in terms of length.

But in terms of mass, there are some very heavy things today, but they’re mostly in the water. And we don’t know for sure why there were these eighty ton animals on land back then and there aren’t now. Yeah. It could be that it was just the a sort of a slow build.

And there was a bit of an arms race between the meat eating and the herbivorous dinosaurs. And it just happened to work out that way for a while. And we saw it again at other times in the past too. But we just don’t happen to have anything quite so big right now from a c a combination of factors.

speaker-1 (12:37.038)
You do want to be cautious though when it comes to estimating dinosaur sizes. Like you were saying, Garrett, we have these huge estimates of some sauropods, but that’s on the upper end. We talked about this in episode 513, too, titled Updates on Dinosaur Growth and Development. Scientists had cautioned how to estimate the sizes and body shapes of extinct animals. And it all comes down to being careful what animals you compare it to because

Since we only know incomplete fossils in many cases of the extinct animals, it’s useful to compare them to modern animals when you’re reconstructing the bodies, but modern animals aren’t an exact parallel.

speaker-0 (13:17.72)
Yeah, because the best thing you can compare it to is basically a bird. They have the most similar skeletons and breathing systems and everything, but most birds aren’t hyper carnivorous, you know, apex predators running around on two or four legs. Yeah. Yeah. They’re usually flying and that has a totally different set of adaptations.

speaker-1 (13:40.268)
And the authors had mentioned there seems to be a tendency to overestimate size because sometimes that just gets people more interested when we talk about look how giant this animal was.

speaker-0 (13:49.678)
Yeah. There’s almost always the earliest papers have the highest weight estimates. And then later on when other people look at it, they’re like, wait a second. Yeah. And also compare it a little more closely to relatives rather than just starting from, Look how big this leg is. Maybe it could have had this much meat around it.

speaker-1 (13:59.021)
Winnow it down.

speaker-1 (14:09.176)
Yeah. So building on that, we have our next new news item, which was published in Cretaceous Research by Evan Thomas Saida. And that’s about how when estimating how dinosaurs grew, some models may be missing some data points. So some recent dinosaur growth models that were saying maybe underfit. That means the model’s too simple and it has some biases or errors. They may not emphasize enough variation, whether that’s based on sex or species.

Now we do know it’s hard to study how dinosaurs grew, especially because there’s a lack of fossils. The fossil record is famously incomplete. And size is influenced by a lot of factors: nutrition, sexual variation, genetic variation, just to name a few. Some case studies that the author mentioned, one that examined Diplodocus growth, which we talked about way back in episode 509. They said that study didn’t account for variability in the animals. So

The author applied a different growth model and found that three different growth patterns could fit the Diplodocus specimens that were involved. And not all were realistic. There was one that showed exponential growth. So it’s like obviously it’s not exponentially growing. But they found that the hypothesis that Diplodocus halorum grew more slowly over longer periods than another species, an unnamed species of Diplodocus, didn’t work based on the evidence used. They had six specimens as part of the evidence, five of

This unnamed species, and then one of Diplodicus halorum. Another example they cited is the study of tyrannosaur growth. They said that that particular study didn’t account for variability in the animals, intraspecific variation in adult body mass of T Rex, for example, just different adult T Rex could have some variation. And also, there was a big question there of how fast does T-Rex grow in early life?

speaker-0 (16:03.18)
Yeah, ’cause we just don’t have many fossils from early life.

speaker-1 (16:06.554)
Although we have a few new ones now, but I’ll get into that in a little bit. And then there’s the sexual dimorphism aspect. So in some animals, like turtles, females are larger than males, so they can lay more eggs, or as the author put it, maximize reproductive output. But with dinosaurs, eggs were often much smaller compared to the adults. So it’s unlikely that, say, titanosaur females needed to be much larger than males to lay lots of eggs.

speaker-0 (16:30.268)
interesting. I never knew that connection between size and egg laying because we often talk about how a lot of times female birds are bigger than male birds. But I didn’t think about, yeah, they have to have eggs. Like that kiwi bird that has an egg that’s like half the size of its body. It would be helpful to have a larger body in that case. Yeah.

speaker-1 (16:52.334)
I’d say. It’s also unlikely that there needed to be much larger female tyrannosaurs than males to allow them to hunt while gestating. That their metabolism while gestating the eggs would only be a fraction compared to, say, what a kiwi goes through. Speaking of Kiwis, it’s not quite half. It’s like they said around 20% of its body size. yeah. It’s still very long.

speaker-0 (17:14.574)
I was thinking the longest dimension is like half, you know, like the length of the egg versus the length of the kiwi bulk of their body.

speaker-1 (17:25.869)
Well, it’s possible that more male dinosaur species were larger than females of the same species too. We see this in lots of crocodilians and with some birds. But even in species with sexual dimorphisms, sex alone only explains a small amount of variation. There’s more differences based on environmental conditions.

speaker-0 (17:42.712)
Yeah, like we talk sometimes about how I think it’s Bergman’s rule that animals that are closer to the poles are bigger than animals closer to the equator. And you see it with things like bald eagles. The bald eagles that are up in Alaska and Canada are way bigger than the ones in Florida. Yeah. And it’s the same species. And, you know, even males and females both do that. So and like you were saying, also the amount of food that they get. And we’re talking about these animals over the span of millions of years. Yeah. So there could be

large changes in the environment, it it makes it more complicated, that’s for sure.

speaker-1 (18:16.93)
Yeah, so the bottom line for this paper is you should take into account the variation within a species as well as sexual dimorphism when you’re estimating growth, which can be hard to do.

speaker-0 (18:27.106)
Yeah, a lot of the overview sort of meta-analyses of dinosaur papers end up summarizing as like we overstate what we know and really we don’t know all that much.

speaker-1 (18:41.826)
Although you can extrapolate a lot.

speaker-0 (18:43.712)
You can. And it is useful to have estimated sizes that are using a consistent methodology. So even if we’re saying this titanosaur is ninety tons and this one’s sixty tons and you’re off, hopefully you’re off in a way that the sixty ton one is still two thirds the size of the ninety ton one and you still have a rough idea about how big these animals are. Yeah. Is useful for talking about them and describing them and things.

speaker-1 (19:09.55)
So going the other way, there is a paper by Matthew Dempsey and others published in Biological Reviews, Open Access, that basically says the dinosaurs were likely thicker and heavier than previously estimated. Lots of debate in science. Mm-hmm. So for this paper, they looked at relationships between the dimensions of living soropsid skeletons and the soft tissues around them. So they’re looking at the volume of soft tissues in animals.

speaker-0 (19:22.68)
Yeah.

speaker-1 (19:38.656)
And that helps estimate what that looks like in dinosaurs. And they combine their models with bird and reptile variables, the you know, two closest living relatives. So body mass helps us learn about geography, ecology, form, function, physiology of an animal. So a lot of things, and mass affects behavior too, as well as how an animal moves. For this study, they used three models and three D scans, and then they compared body masses with previous methods. They estimated the body dimensions of.

Fifty-two dinosaurs. It included most major clades and body plans. And they found that dinosaurs had a lot of soft tissue and more mass. They’re not so shrink-wrapped, which is something we’ve talked about before.

speaker-0 (20:20.184)
Yeah. Sometimes there’s a tendency when you draw a dinosaur and you look at the skull with all of its little divots and holes, finestrae and everything, to bring all of those through in your drawing, because that’s what we know about the animal is what its skull looks like in a lot of cases. But later research showed that well, a lot of these animals do have these sort of holes in their skull, but you don’t necessarily see them when they’re alive. There is the soft tissue covering it. And the same is true about the big cubic bones.

boot that they have at the bottom of their hips that wasn’t necessarily super clearly defined, as well as the bones and their arms and their legs. So that shrink wrap effect is kind of an easy place to start when you’re looking at a skeleton because you’re bringing out the details of the skeleton. But when you look at real animals, they tend to have a lot more soft tissue muscles and bone and cartilage and fat and all that.

speaker-1 (21:14.988)
Yeah. So for their study, they had body mass estimates range from less than two hundred grams for the aviolin Achiatornornis to over sixty metric tons for the sauropod patagotitan. Such a wide variety. Mm-hmm. So yeah, there’s a lot of variation and subjectivity when it comes to estimating a dinosaur’s mass.

speaker-0 (21:35.79)
That is interesting that even with a more robust model, more robust dinosaurs, the Patagotitan was still only in the sixty ton range because like you were talking about earlier, some of these titanosaurs being over a hundred tons potentially. And this is a newer estimate, but it’s still not way out there. Right.

speaker-1 (21:58.382)
There was some debate on the dinosaur mailing group. Keep wanting to say dinosaur mailing list. It’s group dinosaur group, yeah. And there was debate that some dinosaurs would be leaner or have lower body fat, because we see this in some rhinos. They’re healthy, but you can see their ribs for some of them, for example. So it just depends on what models and comparisons you use. Yeah. Some things to consider, the authors mentioned, or long neural spines, is the

speaker-0 (22:05.035)
I think it’s just dinosaur group right.

speaker-1 (22:28.59)
Does that mean it had a sail or a hump? Because that could change your mass estimate, like with Acrocanthosaurus. Also osteoderms and body armor. Horns and frills, maybe they weren’t that dense. And then the long necks of sauropods, it’s a much bigger proportion of their total body mass compared to other dinosaurs. And changes in their neck posture could change their center of mass more than in other animals. Theropods also seem to have slender limbs for their mass, and ornithiscans have seemingly robust limbs for their mass.

speaker-0 (22:57.238)
Yeah. And that is generally how you see them depicted as the theropods like a little bit leaner, long legs. ‘Cause that’s what you see in animals that are hunting usually, whereas the herbivorous ones are often a little bit chunkier. They’re a little more sturdy. Yeah. ‘Cause they’re not usually in these larger animals cases, not outrunning predators. It’s more about being big and bulky and able to, you know.

speaker-1 (23:22.734)
Look at me, I’m too hard to take down.

speaker-0 (23:24.92)
Yeah. And also just being able to like stand your ground successfully. Yeah.

speaker-1 (23:30.67)
So another interesting question about dinosaur growth is did climate affect how big they got? Or how much did it affect their body size evolution? And that’s hard to say, is the conclusion of this paper by Lauren Wilson and others. This was published in Paleontology and also open access. So we’ll have a link in our show notes. You can check it out for yourself.

speaker-0 (23:49.122)
Yeah. People used to always say when we were kids, dinosaurs were so big in the Mesozoic ’cause it was so warm. And when it’s warm, you can get huge and there was more oxygen. So the more oxygen to breathe made them much larger. But then you see things like how there was the ice age, recent ice age in the Pleistocene, and we had huge animals. Yeah. Because cold can be good for getting really big too, because it actually helps you be more efficient with controlling your body temperature. Yeah. And sometimes getting really big.

In a hot environment can be really difficult because you overheat. So it’s complicated.

speaker-1 (24:25.492)
And apparently birds and mammals often get smaller with anthropogenic global warming. That’s warming caused by humans. As for dinosaurs, after the Jenkins event, this is the Torshian Oceanic Anoxic event in the Jurassic, about a hundred and eighty-three million years ago, there were a lot of volcanic eruptions, the earth heat up and then the oceans lost oxygen. So wasn’t great for everybody, I imagine. Mm-hmm.

So after that happened, sauropods moved to warmer and drier environments, and theropods moved to cooler, wetter climates. Ornithiscans had a similar pattern, but it happened way later in the late Cretaceous, about 94 million years ago, during the Cretaceous, well, after the Cretaceous thermal maximum. And that was a time of extreme heat. So how much was this change in climate and moving to the different or preferred climates related to the dinosaurs getting bigger? Well, they collected

paleogeographic data for 339 dinosaur species, basically where in the world they were, and femoral circumferences. That’s a proxy for body mass by looking at their thigh bones.

speaker-0 (25:33.292)
Yeah, bigger legs mean more massive animal, usually. Yeah.

speaker-1 (25:38.594)
They found no clear effect of climate on the evolution of sauropod body size. Same with theropods and ornithiscans. Wow. But they did find with ornithiscans a quote, significant association between ancestral increases in size and decreases in local paleo temperature along ornithiscan branches after the Jenkins event. End quote. So it may be that moving to cooler climates may have driven the rate or amount of change in body size along their lineages, but not.

quote their interspecific variation in size at any given time.

speaker-0 (26:10.794)
Okay. So on a a very long time scale, the fact that they moved to cooler places might have led to l larger species, but within a species you didn’t have variations based on temperature. Yeah.

speaker-1 (26:27.086)
There’s some things to consider, the authors said, like there’s some preservation biases. Some areas we’ve collected more fossils than others. They were just favored areas. Sometimes we only know a partial specimen for a dinosaur, so that’s really hard to estimate a body mass. Also, some dinosaurs changed a lot in size as they grew up, and we don’t know the ontogeny for every dinosaur. We don’t know exactly how it grew. And we don’t know the maximum body size, as we mentioned before. The largest known

Triassic theropods that we know from individuals, they were all still growing rapidly, for example. So we don’t even know how big they got. So the conclusion is that the sample size really affects whether or not you can use these macroevolutionary patterns. And we just need even more data and study it more, more body-sized data sets and phylogenies to draw better conclusions. So I think they haven’t ruled it out. It’s just hard to say definitively.

speaker-0 (27:17.752)
That climate didn’t affect body size. They haven’t ruled that out.

speaker-1 (27:21.526)
Yeah, I think so. That was the impression I got.

speaker-0 (27:23.884)
Yeah. I mean, certainly when you said that there isn’t s clear evidence of climate affecting sauropods or theropods or ornithiscids. Yeah. That makes sense. And also when you look at the family tree of, say, sauropods, you do have a group that got really big at the end of the Jurassic. But then you have groups when it was pretty hot in the Cretaceous that were getting smaller. Yeah. And some of those things were due to being on islands and having less resources available, but some of them seem to be kind of

Arbitrary. Like why was that one small? There was just a niche that opened up.

speaker-1 (27:57.602)
And sometimes on islands you had small sauropods and your regular medium large sauropods.

speaker-0 (28:03.142)
Yeah, exactly. It’s all about like what niche that animal could evolve into, which is a lot more complicated than just the temperature.

speaker-1 (28:11.342)
But I’m sure there’s a lot of factors that go into it. So next up, there was a paper by Kathleen Dolman and others published in iScience that found that scans of early Triassic Archosauromorph fossils show that this group, and that group includes dinosaurs, had a variety of growth strategies from almost the beginning. So Archosauromorphs started in the early Triassic. This is about 252 million years ago. Today they’re birds and crocodilians, so they’re still around. And birds grow fast, but crocodilians grow slow.

It turns out that in the early Triassic, Archosauromorphs were already had different growth rates. Some were fast, some were slow. And that means that fast growth is not a plesiomorphic trait or an ancestral trait in Archisoromorphs. It’s not like they were all growing fast and then eventually the crocodilians got slower. The evolution of growth is important to know because growth strategies are linked to things like adult size, immune resilience, maturation, and basal metabolic rates.

Now, bone tissue types can show different growth rates. For example, if you see disorganized woven fiber bone, that’s associated with fast growth, rapid growth. But if you see regular lamellar bone, that shows slower growth. That’s thin alternating layers or plate-like sheets in the bones. So with that in mind, for this study, they looked at nine limb bones, arm and leg bones, and did micro CT scans. These bones are from South Africa, the Karo Basin, and there’s

Enough differences in these bones that they said there’s at least nine distinct taxa here, but there’s not enough detail in the bones to confidently assign them. They just know there’s enough variation in the bone tissue to show they’re different. And for context, there’s fewer than 20 named Archosauromorph taxa from the early Triassic. So this adds a lot. They said they need to study more fossils though to see that broader evolutionary patterns.

speaker-0 (30:00.587)
Interesting.

speaker-0 (30:05.422)
Yeah, that is a very interesting. We’ve talked before about how sometimes you have a site and there are a bunch of footprints and you can say, okay, we know there were theropods here, we know there were sauropods here, but we haven’t actually found any of their fossils yet. And sometimes it expands the known range of them or the known time period when a group of dinosaurs was around, but you can’t nail it down to a species. I don’t remember ever seeing taking basically a bone fragment.

looking at it under a microscope and saying like, this bone has a different structure from that bone and that bone and that bone and that bone and therefore we can tell they’re all different species. It’s a a very interesting approach.

speaker-1 (30:44.77)
Yeah, I mean we talk all the time about different tools, different techniques that come out in paleontology or sometimes other science other studies, and you bring it into paleontology and then all of a sudden you have a completely different view of a bone that people dug up hundred, two hundred years ago.

speaker-0 (31:03.084)
Yeah, and wasn’t useful for a long time. Yeah.

speaker-1 (31:06.092)
Now, how scales grew as dinosaurs grew can also give us some information on how they lived. That’s what this next paper by Nathan James Enriquez and others is about. This was published in Journal of Anatomy, Open Access. Now, scales have a lot of functions. They can help with moving, visual signaling, protection against bacteria or parasites, as well as protection against UV rays and physical damage, and they can help with preventing desiccation or drying out.

speaker-0 (31:32.494)
That’s funny because a lot of times people reference having something scaly about skin, meaning it’s dried out. But if you had scales you wouldn’t have dried out in the first place, maybe.

speaker-1 (31:42.424)
Yeah, maybe. So the shape and the size of the scale are related to their function. Some animals shift ecological niches as they grow up. So these authors were looking at do their scales change too? Because scales may look different in juveniles and adults, and they might have different functions. Like maybe sometimes they’re for attracting mates. So you the scales change when you’re older. Mm-hmm. They studied the scale growth in the Ceratopsid Casmosaurus and the Hadrosaurid prosperoliphus.

And that’s because we know their skin for different ages. Wow. Yeah. And they compared how the scales looked in juveniles and adults. The scale shape stayed pretty much the same in both, although the Casmosaurus scales got wider as it grew up. So it doesn’t seem like there’s anything mating related. Size was, as they put it, largely non adaptive. It just doesn’t seem that the scales were for display to attract mates. They found reticulate scales on Casmosaurus. That’s the first ones found for a ceratopsid.

It was on the right foot of one. These are small scales. And being on the foot, it’s in quote reticulate scales, because it’s not exactly the same as the ones we see on birds. Pro Serolifus has a quote novel type of basement scale. Those are scales that are small, not overlapping, and they surround and connect larger scales.

speaker-0 (33:00.01)
Yeah. I think of as more they call base mint scales, but I feel like you could just call base scales. Yeah. ‘Cause they’re sort of like the default scale that’s around that don’t really stand out.

speaker-1 (33:10.542)
I think I’ve heard both terms. So instead of being rounded or polygonal like in reptiles, they make this irregular scale outlines with protrusions that can be sharp or angular or blunt and rounded. So things are sticking out. We see this in Seroliphus too. It’s possible that the frills and crests of adult ceratopsians and hadrosaurs were also covered by scales, which would be interesting, especially if they got these protrusions. So they compared them to eight modern reptiles.

Some crocodilians, skinks, and snakes. And it seems that the general scale shape is likely species-specific and consistent as they grow up.

speaker-0 (33:48.31)
Okay, so a little bit of species recognition. One of those details that is lost for almost every species, what their scales looked like. And we’ll get into more dinosaur growth stories in just a moment, but first we’re gonna pause for a quick sponsor break.

speaker-1 (33:50.669)
Yeah.

speaker-1 (34:08.141)
So we’ve talked a bit about different ways that growth affects, I guess, lifestyles. This next bit is about how growth affects parental care. And I’ll just start with a quick recap. In our last episode, episode 570, we talked about Tom Holtz Jr.’s paper, Bringing Up Baby, where he basically said dinosaurs were like latchkey kids and mammal parents are or were more like helicopter parents. Because

The dinosaurs in the Mesozoic seem to kind of be more independent, whereas with mammals, we tend to rear our young for a longer period of time. Mm-hmm.

speaker-0 (34:50.222)
I mean you kinda have to if they’re drinking milk. Not a lot of options. But dinosaurs could go either way.

speaker-1 (34:55.244)
Yeah. And in the case of dinosaurs, it’s even more interesting because sometimes some dinosaurs filled a totally different niche as a baby or a juvenile compared to the adult. But then with mammals, because you’ve got the babies or the young with the adults, they kind of they’re doing the same things, eating the same things, living in the same places.

speaker-0 (35:16.184)
Yeah, ’cause they can basically stay with their parent until they’re ready to do the thing the parent is doing. Yeah. They don’t have to figure out their own solution when they’re too small or not skilled enough to get whatever food that the adults might be eating.

speaker-1 (35:31.246)
Exactly. So breaking that down a little bit more, I’m gonna start with theropods, specifically tyrannosaurs. So tyrannosaur hatchlings may have left their nest shortly after hatching and hunted. This was published by Nicholas Longrich and others in biology. It’s open access. You might have heard about this one. It was kind of big news when it first came out, because it was about tyrannosaurus babies. Mm-hmm. Now young dinosaurs and eggs are rare.

And we don’t know much about the early life of tyrannosaurs. In this case, they studied hatchlings of both Tyrannosaurus Rex and Gorgosaurus. All these hatchlings were under one year old. They were all fragments found in drawers with porous bones. That’s what shows that they’re from young dinosaurs. The largest one weighed five and a half pounds or two and a half kilograms, which is less than point one percent of the adult mass.

speaker-0 (36:23.147)
Yeah, ’cause you’re talking about l more like five tons versus five pounds.

speaker-1 (36:27.808)
And they may have been even smaller when they first hatched, more like 3.7 pounds or 1.7 kilograms. Yeah. So they CT scanned the specimens. There’s bones and teeth. Tyrannosaurs had relatively small hatchlings, it turns out, compared to modern birds. And this suggests that they laid a lot of eggs and provided relatively little care for hatchlings, which is interesting because we often talk about like, the tyrannosaurs gave the parental care. Mm-hmm.

speaker-0 (36:34.072)
Makes sense, those are small eggs.

speaker-1 (36:57.592)
They estimated that there might have been twenty eggs in a small T Rex clutch, thirty with a large one, which is a lot, fifteen eggs in a Gorgosaurus clutch, still a lot. And they did have proportionally larger offspring than most reptiles, but they were relatively smaller than birds.

speaker-0 (37:13.192)
Interesting. The point one percent is actually on the bigger end for a reptile. I guess if you look at a baby sea turtle, it is tiny. It’s just like a few grams. So and but they put way more in a nest, like you were saying. Yeah.

speaker-1 (37:26.904)
So they saw some bone remodeling. It’s likely from when the tyrannos were moving around soon after hatching. We mentioned that it’s doing some repair and regrowth because of the stress from walking around. The bones remodel under stress. They get thicker and denser as the animal goes from not moving in the egg to hatching and moving around. Titanosaur hatchlings, bone density increased too around when they hatched and increased as they grew.

With these tyrannosaurs, the hatchling fossils looked a lot like adult fossils. And the teeth wear shows that they fed on relatively large vertebrates. Hmm. So the thinking is that tyrannosaurs, the reproductive strategy is likely somewhere in between primitive reptiles with limited parental care and advanced parental care seen in birds. It’s likely there was only one parent with dinosaurs, not two like with birds. You get one parent with crocodilians and many basil birds too. And tyrannosaurs didn’t seem to be stuck in the nest. They

Left soon after hatching and likely hunted.

speaker-0 (38:26.19)
Yeah, I guess if you have wear on the teeth that shows that they were chewing on bone. Something. Yeah. Or at least scraping up against bone occasionally, that means that it was probably wasn’t parents feeding them scraps of meat unless I guess they gave a scrap that had bone on it. Maybe it is so hard to figure these things out.

speaker-1 (38:41.198)
Hard to say.

But keeping with Tyrannosaurus, there was a recent paper that found it took Tyrannosaurus Rex 40 years to reach its full size. And this was published in Pier J, it’s open access by Hollywood. And 40 years is 15 years longer than previous estimates. Before, age 25 was considered adult size, and Tyrannosaurus Rex was considered to have a lifespan of only like 30-ish years, and full size being about eight tons. So

How did they come to this conclusion of 40 years? They found these previously hidden growth rings in the fossils. So they analyzed 17 tyrannosaur individuals, young juveniles to adults, the femora and tibiae, these are leg bones, and the smallest one was at least 10 years old when it died. So you’re looking at the lags, they used specialized lighting, circularly polarized and cross-polarized light, to study the thin slices.

speaker-0 (39:17.762)
Yeah, ’cause that’s a lot longer.

speaker-1 (39:43.052)
And they found growth rings that were difficult to detect using other methods, which means that there were more lags there than they previously thought.

speaker-0 (39:50.26)
Interesting, because circular polarized light is usually what they use. Maybe the cross polarized light. Yeah. I mean, that’s that’s just more of like a linear filter, but I guess that could make a difference. Or they were just looking closer. A lot of times you kind of see what you expect to see on these types of scans. So it makes sense that you might have only noticed the obvious ones if everybody is always pointing out the obvious ones. And it takes someone looking at it more closely to notice a few.

More faint lags near the center. Yeah.

speaker-1 (40:25.666)
Then they used statistical models to combine information from multiple specimens just to get a better idea of how T-Rex grew, to show its growth trajectory. And they found that T Rex grew at a steady pace over several decades, which would have helped with younger tyrannosaurs being in different niches as they grew up, because what they ate, how they lived and interacted with other species would have been different, especially it’s growing at this steady pace instead of a fast growth. Mm-hmm. There’s some limitations to the study.

They acknowledge, you know, there’s just not enough fossils, especially of young or small individuals and old and large ones. So this study is best suited for middle-sized, middle-aged tyrannosaurus wrecks.

speaker-0 (41:05.034)
Okay, so it might not have been purely linear all the way from hatching. Yeah. Maybe there was a period of faster growth for a little bit and then when they reached middle age ish, then they sort of leveled it out. Well, not leveled out, became more linear.

speaker-1 (41:19.906)
Yeah, and different pressures can also affect growth. A lack of resources would slow growth, for example. They found no strong link from living animals to support the idea that being full size is related to sexual maturity. For example, so many birds reach adult size so quickly before they’re sexually mature. And mammals apparently don’t have a consistent pattern, which is interesting. For this study, they also looked at Jane and Petey, which are now known to be nanotyranous specimens.

And Jane and Petey had different growth patterns from Tyrannosaurus Rex. I’m guessing that they at least started the study before or when the nano paper came out. But anyway, it is more data supporting nano tyrannus being valid. And they did mention that paper in the addendum that they were pleased to learn that study complimented theirs.

speaker-0 (42:05.518)
Yeah, that was one of the thoughts about the growth rate of T Rex, because a lot of those papers looking at the growth rate of T Rex would put Jane and Petey and some of these other now nano tyrannous specimens on the plot. And it I think made more of a pronounced S shape curve as a result because you get these later, older individuals who are on the smaller scale.

speaker-1 (42:30.732)
Yeah, yeah, it would definitely change in how we see things. Just a quick note about parental care in dinosaurs. Birds grow fast, but apparently it’s accelerated because of parental care. Because they can reach their adult body size within the first year, usually. Four months, I think, was the fastest I heard about. A T Rex took longer. It’s unknown the degree of parental care they got. It’s entirely possible there was parental care, like we were just talking about with the hatchlings.

speaker-0 (42:45.71)
Yeah, sometimes just a couple of months.

speaker-1 (42:58.326)
And if so, that early period could have accelerated its growth, and then it wouldn’t be following the same growth model later in life. And middle-aged. Sticking with the tyrannosaurs, just wanna do a quick recap. This was from episode 513, updates on dinosaur growth and development, where we talked about Displetosaurus, how the skull bones helped show how the dinosaur changed or really didn’t change as it grew up. Because they looked at

speaker-0 (43:05.07)
Mm-hmm.

speaker-1 (43:27.394)
different parts of the skull and they found that it looks the same as Dyspletosaurus grew up. It’s constrained throughout ontogeny, as the scientists put it. Which is helpful in some ways because then you can confidently identify no matter the age, whether a fossil is Dyspletosaurus or another dinosaur that lived around the same time and place, Gorgosaurus.

speaker-0 (43:48.054)
Yeah, that’s certainly helpful because we talk a lot about how a lot of times baby dinosaurs look like earlier, more basal forms of similar dinosaurs. And that can make it really hard to identify a baby dinosaur species. And a lot of times you end up naming them a different species, and then later on people realize that, it just looked different because it was a baby. Yeah. So if they look the same their whole life, that is much easier for paleontologists.

speaker-1 (44:13.068)
Yes. Easier to put together that growth series, too. Mm-hmm. Our last theropod we’re going talk about is Ceratosaurus and how it grew more than nine times faster than its fellow Ceratosaurs. This was published by Riley Sombathy and others in the Journal of Anatomy. It’s open access. And Ceratosaurus was known, it’s been known for a while for growing fast. It’s also the only theropod currently known with osteoderms on its body. Mm-hmm.

For this paper, they described bone tissues of three leg bones, two ribs, and one osteoderm from four different individuals of ceratosaurus. And they compared annual growth rates from three individuals to five other ceratosaurs. So they looked at lags, remodeled bones, and fibers. And the bone tissue in the legs looks similar to the bone tissue in modern bird legs. And bird legs represent some of the fastest growing bones. There was variation in the lags, in the legs.

There were lags in other bones too, but some of them didn’t have lags. Some of them had lags at regular intervals, and some were just all over the place. Ceratosaurus is one of the earliest diverging ceratosaurs, and it’s also the fastest growing. Their maximum annual growth rates were on average at least nine times faster compared to other Cerratosaurins. Oof. Yeah. And later Ceratosaurs grew more slowly, and they were generally smaller, which it could be because of environmental stressors, so they didn’t want to use as much energy to grow.

But some later Ceratosaurus include like Mechikosaurus and Majungasaurus, which were smaller. There’s no data from juveniles though, which does limit the study. So they’re saying that they need more samples from younger individuals to figure out when exactly Ceratosaurus started growing so quickly. Sounds like we just need more baby dinosaurs.

speaker-0 (45:55.886)
Mm-hmm. They’re so easy to find. That should take no time at all.

speaker-1 (45:59.264)
All right, that covers the theropods for this episode. Moving on to the next group of dinosaurs, the sauropods. Starting with a nude tiny young sauropodomorph sheds light on how early dinosaurs grew. This was published by Leomar Santos Campos and others in Paleo World. So in the late Triassic and what’s now Brazil and Argentina, that shows the earliest stages of dinosaurs diversifying and spreading out. In this paper, they described one of the smallest known.

Dinosaurs from the Triassic and what’s now southern Brazil and how it grew. The fossils include an arm bone, parts of the hands, and part of a vertebra. So in total, they got five bones. And these fossils were found back in 1999. They’re all tiny, they’re all smaller than 57 millimeters long. Hmm. We went from big serratosaurus to small sauropodomorph. Now, big sauropods, of course, they’re known for having the long neck, the columnar legs, the barrel-shaped body, and the small head.

speaker-0 (46:44.706)
Woof, those are small. Mm-hmm.

speaker-0 (46:50.412)
Yeah.

speaker-1 (46:57.176)
But that body plan changed a lot over time before settling in, and that’s for multiple groups. And soropodomorphs didn’t all evolve linearly from walking on two legs to walking on twos or fours to eventually walking on all fours. It’s kind of all over the place. And late Triassic and early Jurassic Soropodomorphs all had different strategies, which may mean that the body plan was adapted in different ways depending on their locomotor needs.

speaker-0 (47:21.947)
interesting. Yeah. So if they needed to move more quickly or slower. Yeah.

speaker-1 (47:26.476)
Yeah. for this one, it’s some sort of juvenile sauropodomorph, and there’s one lag. There’s also some bone remodeling. Again, bone regrows when under stress, like when walking or running, and it was about midway through its second growth cycle. Based on its bones, we can see continuous and rapid growth early on, but it’s an intermediate growth rate compared to other Jurassic juveniles, so it grew more slowly. On the other hand, the titanosaur nucensorus grew quickly but differently than expected.

This was published in historical biology by Virginia Zurigas and others. Nucensorus was a saltosaurus, titanosaurus dinosaur that lived in the Lake Cretaceous in what is now Argentina, and it had armor-like osteoderms. It’s small for a sauropod, we do know most of its skeleton. It was about 23 to 30 feet or 7 to 9 meters long. For this paper, they described an incomplete juvenile nucensorus that was about 44 to 64% of an adult size.

They compared it to adult specimens and found that various bones fused late during ontogeny, while it was growing up, or at least it was later than in the juvenile they studied. They also found that the air sacs in the bones got more developed as it got older. And they found that it grew allometrically, so different parts of the body grew at different rates. This contrasts with previous hypotheses that titanosaurs grew isometrically, meaning all their body parts grew at about the same rate.

speaker-0 (48:50.956)
Yeah. And isometric growth where they grow at about the same rate is usually correlated to animals that are sort of in the same niche.

speaker-1 (48:58.978)
Yeah. Now, based on histology, nukensores grew quickly, but there’s at least one lag or growth mark, and that also challenges previous hypotheses on how sauropods grew, because previous hypotheses were that they grew quickly and not interrupted. They didn’t pause for growth throughout the year, like in winter when there’s fewer resources, and that interrupted growth only happened when it was older. But this is showing that’s not the case. And giant sauropods

Lived for a long time. We talked about that in episode 509. New sauropods in the Yale Peabody has reopened, where a team studied Diplodocus and Supersaurus. Anyway, this brings us to our listener question, which came from Matt. Thank you, Matt. This question was posed a long time ago, but it made sense to include in this episode because it has to do with sauropod growth. I’m paraphrasing here, but if you start off with a hatchling sauropod that’s small enough to feed in your lap, and then it potentially grows into a treetop browsing giant in a decade.

Mm-hmm. The question is about how its diet would have changed over time and how much would it need to eat so it could grow so large? Which is a great question. And we’ve covered bits and pieces of this in past episodes, which we had to do some digging to find.

speaker-0 (50:08.268)
Yeah. As soon as you it pointed out this listener question to me, I was like, I know we’ve talked about this. Yeah. I just can’t remember when.

speaker-1 (50:15.704)
But yeah, sauropods, they were eating machines. And once they were big enough, they could use those long necks to swing over big areas, kind of like lawnmowers, and then just eat from one spot.

speaker-0 (50:26.018)
Or maybe in the case of the high browsers, like a a chainsaw and a stick. Trimming less of trees.

speaker-1 (50:30.229)
yeah.

But what about his hatchlings? Well, back in episode 220, we talked about Musaurus. Some hatchlings had been found near a nest with eggs, so maybe there was some parental care there. A young musaurus had awkward proportions. It started off its life on four legs, and then its body proportions changed, and then as an adult, it was on two legs. Its teeth were a little different too. It’s possible the young ones ate insects as well as plants, which would be good for getting more protein. Mm-hmm.

speaker-0 (51:00.568)
To a growing mooseurus need.

speaker-1 (51:02.54)
Not just mussaurus, but yeah, for growing in general, you need protein and nutrients. And in episode 256, we covered an SVP talk that rated which foods were best for young growing sawpods.

speaker-0 (51:13.56)
Yeah, that was a really good one. I think it was Carol G that presented it. Yeah. And she was talking about her super food, as she called it for the dinosaurs, were horse tails. Basically, Equicetum is like the official genus name. They were around through all of the Mesozoics. They would have basically been available for every herbivore. But they found a way to determine how much energy comes from these plants by putting microbes in a syringe and then measuring the amount of gas coming off of it, which

speaker-1 (51:23.574)
Yes.

speaker-0 (51:42.85)
Correlates the amount of fermentation that’s done, and more gas means there’s more energy being released. And then they have a five-star system for it. And they gave horsetails five stars because they produce a lot of energy and very quickly, which is good for having a short digestion time, which is what a lot of those little sauropods and some of those other small herbivores, especially in places like the Triassic, would have had. And so those young animals, in addition to digesting faster, they also need a lot of energy to grow.

quickly and so that equicetum is just perfect for them.

speaker-1 (52:16.546)
Yeah, because there’s a few ways to get that extra energy and protein. You just eat more, you digest better, you pick better food, or you digest faster because you have a higher body temperature. And horsetails, they were quick to digest, they give you a lot of energy. They were everywhere too. Cause they could get to three meters tall back in the Cretaceous. And even if you ate at all, the rhizomes, the underground plant stem that acts as like a storage organ that allows plants to spread and reproduce, they reproduce again, including every spring. So the horsetails come back.

speaker-0 (52:45.566)
Kind of like a weed. Yeah. If you don’t get the whole root with it, it’s just gonna come right back.

speaker-1 (52:49.698)
Yeah. And a lot of modern animals eat horse tails too, like trumpeter swans, they eat them after breeding. So do some geese. Those are good times to get more nutrients. It’s possible that juveniles and hatchlings ate the shoots of horsetails. Back to the sauropods. Horse tails also were better than grass, although there was no grass in the Jurassic. cycads they found were not great. But as the sauropod got bigger, horse tails didn’t matter as much.

In episode 552, What Dinosaurs Ate, we talked about the gut contents of a subadult Diamentinosaurus sauropod. Some bones were unfused, so that’s how we know it’s a subadult. It was at least 36 feet or eleven meters long, so it was a good size. And in this one, there were gut contents, plant fossils in its abdomen. They found a lot of plants. There were conifers, plants with seeds, flowering plants, also known as angiosperms. And there was a layer of skin with scales that were covered a lot of the gut contents, which is how they knew it was gut contents.

speaker-0 (53:47.864)
Probably its own skin. Yeah. Not something it ate. Yes.

speaker-1 (53:50.51)
And they determined, well, this sauropod was not a picky eater and it did not chew its food. There were no gastroliths either. It relied on fermentation and gut bacteria, therefore, to digest its food. And there were a lot of small shoots and sea pods, which may mean it went for new growth in plants. That’s easier to digest. It also showed it ate low and high-growing plants. So this find supports the hypothesis that sauropods were bulk feeders eating whatever food was in reach that it could handle.

So as a hatchling, it would have had to eat plants lower to the ground. As it grew, it could eat more types of plants. And then presumably as an adult, it could eat even more types of plants.

speaker-0 (54:27.948)
Yeah, because as you mentioned, one of the main strategies for these larger herbivores is having a large gut so that it can sit in there longer and potentially at a higher temperature because of that gigantothermy they have going on. The big body helps you warm it up more. Yeah. And then on top of that, we were talking about the long neck sort of sweeping back and forth, adding to efficiency for just consuming a lot. In that huge body where you’re looking for efficiency and movement.

You don’t have time to run around trying to find the optimal food everywhere. You just gobble up everything that you can possibly digest. Whereas the babies, it takes them a lot less energy to move around and they don’t need as much food to fill their stomach. So it makes sense that they would walk around and be pickier, find the plants that give them the most caloric value, and that they could digest in a shorter amount of time. And so that’s how you end up with different diets for the babies versus the adults.

speaker-1 (55:26.274)
Yeah. So that’s our sauropods. We’ve got one last group, the Ornithiscians. Starting with the basal ornithopod, Chang Chunsaurus was one of the slowest growing dinosaurs that we know of. Talk about fast growing ones, now we’re talking about slow growing ones.

speaker-0 (55:42.85)
I wouldn’t have thought an ornithopod would be a slow growing one.

speaker-1 (55:45.784)
Yeah. Well, this was published in paleoecology by Long Han Wang and others. And Chang Chunsaurus was a small herbivorous Neornithiscian, a basal ornithopod dinosaur from the Cretaceous and what’s now China. It was named back in 2005. It’s got a combination of features like early and later ornithopods. For this study, they looked at tissue microstructure. Specifically, they looked at seven femoras, so thigh bones, and there were lags in them ranging from one to two up to eleven to fourteen.

Some of them were lost though from bone remodeling, so they estimated the lost lags. But anyway, they’ve got juvenile, subadults, and adults that they were studying. And they found that it grew slowly, had a slow growth rate. And not only that, it was one of the slowest known dinosaurs in terms of growth. It reached sexual maturity around seven to eight years old, which is also late compared to most small basal neornothiscians. And it reached adult size by around age 14. Yeah.

speaker-0 (56:42.697)
that is kind of slow. Yeah.

speaker-1 (56:44.616)
And it was relatively small, it was about 3.3 feet or a meter long, especially compared to its closest relative Jeholosaurus. Now the slow growth might be linked to living in a semi-arid environment. Maybe there was environmental stress. It could get pretty hot, or there just weren’t as many plants around as when its closest relative live. So again, environmental factors. Going back to parental care.

speaker-0 (56:48.455)
man.

speaker-1 (57:09.718)
Myasaura grew in a way that it needed a lot of parental care as a hatchling, which might not be surprising given its name, the Good Mother. This was published by Hugo Burr and others in scientific reports and it’s open access. They use the inferred metabolic rate for newborn or neonatomyasora, both the rate when resting and maximum activity levels.

speaker-0 (57:16.782)
Yeah, living up to the name. Yeah.

speaker-1 (57:32.342)
And they determined how much oxygen myosaura used and then compared those minimum and maximum rates of oxygen use as a way to figure out how active they were. And that’s one way to figure out how much parental care they needed. Baby birds that forage alone as soon as they hatch have a higher metabolic rate. So if the resting rate and the active rates are the same, it seems that they wouldn’t be too active and they’d be relying more on their parents for help. Although this doesn’t apply to some shorebirds that live in cold, windy environments, because that just

It takes a lot of energy to keep themselves warm. But the idea is if you have the similar rates, then you’re probably getting a lot of parental care. They used a statistical tool that could build models based on phylogenetic information, animal traits, and how closely they’re related to each other, and they included data from modern animals, mammals, birds, amphibians, crocodiles, lizards, and turtles. They found the myasaura resting metabolic rate was similar to fast-growing endotherms today, or warm-blooded animals.

And oxygen use is similar to birds today that need, as they put it, intensive parental care. Altricial birds, which depend heavily on their parents to survive. So they estimated based on all this that myosaurus stayed in its nest for forty to seventy-five days after hatching. That’s based on estimates of babies ages found in and outside the nests. And they likely needed a lot of care from their parents during that time, especially when it came to food and protection.

speaker-0 (58:52.406)
Yeah. If you’re gonna stay in the nest for two months, yeah. You’re gonna need a little parental care.

speaker-1 (58:57.102)
They needed more than tyrannosaurus, it sounds like.

speaker-0 (58:59.328)
Yeah. Although we don’t have any good T Rex nests to based on yet.

speaker-1 (59:03.746)
Not yet. Next up, the Hadrosaur Gripposaurus grew mostly isometrically, meaning everything grew at the same rate. There was a study done in 2022 by Jordan Mallon and others in the Anatomical Record that’s open access. And then there was additional information they published, a commentary this year, the same team. Also open access. So in 2022, they studied the two smallest known gripposaurus specimens that were about two years old.

Gripposaurus is a hadrosaur that lived in the Lake Cretaceous and what’s now Alberta and Canada and Montana and Utah in the US, also possibly Texas. It’s got a big nose. It was named back in 1913 by Lawrence Lamb. The gist of the study is that most of the skull grew isometrically, except for the height of the nasal arch. Yeah, which is what gave it its big nose. That grew allometrically. So that was at a different rate from the rest of the skull bones. Its teeth also changed over time. These juveniles had extra ridges.

speaker-0 (59:41.646)
Yeah.

speaker-0 (59:50.67)
Yeah.

speaker-1 (01:00:02.838)
on the teeth. So maybe they ate slightly different foods. Its arms and legs grew isometrically equally at the same time. So the way it moved stayed the same as it aged. Didn’t change from being two legged only to four legged only or vice versa. But it could switch between two and four legs as needed.

speaker-0 (01:00:18.23)
It’s just its whole life, not just at one point. That’s interesting too, because usually, like we were saying, with isometric growth, that means that it we think it filled a similar ecological niche throughout its life. But things that grow allometrically, especially a big display structure like that, usually they would say that that was probably a sexual selection feature. Yeah. So maybe that nose was a very important thing for the adult gripposaurus. Yeah. When they’re looking for a mate. Could be.

speaker-1 (01:00:47.118)
Or some kind of visual communication, something. So for this commentary, they said they found more information about one of the juveniles they studied that supported their hypotheses. The skeleton had gotten moved around a lot, pieces are now missing or broken, but they recently found this uncataloged photo of the skeleton taken in the basement of the Calgary Courthouse, which shows it was nearly complete and well preserved back then. The skull today is crushed and fragmented, but it was almost entirely intact in the photo. Some of the bones that are missing now are also in the photo.

The neck bones were complete. Unfortunately, most of that’s missing now, and so were the shoulder and arms. So I don’t know what happened. In the caption, they called it trachodon and said it about twelve feet long. The measurements taken back then confirm that Grypposaurus, because now it’s known as Grypposaurus, that its leg probably scaled isometrically, so all parts grew equally. So again, supporting their 2022 hypotheses. Nice. And last up with the Ornithiscans is the small iguanodont Dysalatosaurus, which had some interesting fused bones in its neck.

This was published in papers in paleontology, it’s open access, by Ricardo Rocchi, and others. Disolithosaurus was a small dryasaur iguanodont that lived in the late Jurassic and what is now Tanzania, found in the Tendiguru formation. It’s the best known dryasaurid and only late Jurassic iguanodont known from the southern hemisphere. Wow. And more than 14,000 elements have been found in that formation. There’s a new block that they studied and had as a small semi-articulated specimen. So they did micro CT.

X-rays of this small individual in a block. And then they made a 3D model and they describe more parts of the skeleton. The individual’s between four and five years old. And it’s got a cervical fusion locus, meaning at the neck there’s multiple bones or vertebrae that form a single rigid bone structure. And that’s the first evidence of this in ornithopods. It seems that it evolved independently in multiple archisoromorph lineages. You do see it in some theropods and sauropodomorphs, also pterosaurs and other animals.

And it can help with keeping the head stable when moving or digging. We’re not sure why Disolitosaurus had one though. That could be an interesting follow up. Mm-hmm. Maybe you need more bones. Fourteen thousand elements is pretty good though. Although I don’t know how complete it is.

speaker-0 (01:02:59.224)
Well, that was the full Tendaguru formation, right? Not just this one individual.

speaker-1 (01:03:03.646)
I think more than fourteen thousand Disolidosaurus elements have been found.

speaker-0 (01:03:08.407)
wow. Mm-hmm. That is a lot.

speaker-1 (01:03:10.062)
So more studies, please. And that wraps up our segment on dinosaur growth. We will get into our dinosaur of the day in just a moment, but first we’re going to take a quick break for our sponsors.

speaker-1 (01:03:24.364)
Alright, we have finished talking about dinosaur growth, at least for this episode. We hope you enjoyed it. And now moving on to our dinosaur of the day, Tomba Titanis, which was a request from Dilophosaur Rob via our Patreon and Discord, so thanks. It’s one of the perks of being a dinodal. You can request dinosaurs. Tomba Titanis was a titanosaur, possibly a titanosaur. It’s a sauropod. It lived in the early Cretaceous and what is now Hyogo Prefecture in Japan. It was found in the Oyamashimo Formation.

It walked on all fours. It had a long neck and tail and small head. Only a partial skeleton has been found. The fossils found include teeth, the brain case, lower jaw, parts of the hips, part of a backbone, some ribs, and some tailbones. It took five field seasons to excavate between 2006 and 2010, because it could only be dug up in winter when the water level of the river was lowest. It was described in 2014 by Saigusa and IKeda. The type and only species is

Tampa Titanis Amisitae. That genus name refers to Tamba, the area where the fossils were found. It means tampa titan. And the species name means friendship and refers to the friendship between the two people who found the holotype back in August 2006, which is very sweet. Mm-hmm. There’s unique features in the brain case and tailbones. There’s also neural spines which stick out of the tail that have a strong curve. Tampa Titanis lived in a subhumid to semi-arid climate.

Other dinosaurs that lived around the same time and place include indeterminate ankylosaurs and iguanodonts, the neoceratopsian sasayamagnomnomus, and theropods such as the eutroodontid hypnovenider. And other animals that lived around the same time and place include squaw mates, amphibians, mammals, crustaceans, and mollusks.

speaker-0 (01:05:11.694)
I’ll always think of it as the friendship titan.

speaker-1 (01:05:14.606)
That’s a nice one. I like it. And now our fun fact of the episode, thank you for sticking with us, is that birds may lay large eggs because of their brain sizes. This was published by Stephanie Lecky and Roger Benson in the Royal Society Open Science, so it’s open access. And large non avian dinosaurs laid pretty small eggs. We actually talked about that in this episode. The biggest dino eggs were smaller than the largest bird eggs.

For this study, they analyzed data about the reproduction and anatomy from mammals, birds, and reptiles. Reproduction includes how many eggs or animals are in a litter, the mass of the offspring or babies, etc. They had data from 2,857 living species, 541 birds, 23 crocodilians, 1,187 squawmates, 56 turtles, and 851 mammals.

speaker-0 (01:06:05.634)
Surprised I didn’t have more birds. It’s like ten thousand species. They only took five hundred. And maybe that was enough to get a representative sample.

speaker-1 (01:06:10.284)
Only. man.

Maybe. They also had data for non-avian dinosaur eggs and egg clutches. They had egg mass data for 35 non-avian dinosaurs, including five ornithiscans, twelve theropods, and seventeen sauropods. And they had a clutch mass or clutch size data for three ornithiscians, seven theropods, and three sauropods. Just because it’s fun to talk about that some of the dinosaurs included were like protoceratops, troodon, massospondylus, myasaura, city potty. They found a pattern.

Species with large brains had fewer but larger offspring. For example, the Hawkspill sea turtle has, on average, a clutch of 158 proportionally small eggs that weigh about 29 grams each. That’s about 0.019% of the adult female mass. For comparison, the blue whale has one baby every two to three years that weighs 2,500 kilograms, and that’s 1.6% of the adult female mass. They found that turtles produced the largest number of eggs for their body size.

And birds produce the fewest number of eggs for their body size. And birds and mammals do a lot of parental care, as we’ve talked about in this episode. So it’s possible the non-avian dinosaurs had limited parental care, and they’re more similar to crocodilians than to birds, though it was likely higher in theropods the parental care compared to other types of non-avian dinosaurs. Like we’re talking about with tyrannosaurus. Maybe there was some there. They said it’s indirect evidence, like the size of offspring or the nest structure, et cetera.

When it comes to inferring parental care. But having a lot of small offspring and lower relative clutch mass may mean limited parental care, especially in the non-theropods. Yes. So they might be more like modern crocodilians. Birds developed bigger brains over time, which led to larger offspring, and that meant bigger eggs to support their development, versus dinosaurs had many smaller offspring.

speaker-0 (01:08:00.78)
So the sort of connection between the amount of parental care and the number of eggs, which is also related to the size of the eggs. Yeah. So that it yeah, that is a little indirect.

speaker-1 (01:08:11.586)
Yeah, the increasing brain size may have indirectly influenced nesting behavior, anatomy, and parental care in birds. Larger eggs meant they needed wider pelvic canals to lay the eggs, they needed better ventilated nests for incubating, and then they needed more parental care after hatching.

speaker-0 (01:08:27.074)
Kind of a chicken or the egg, or maybe I should say the chicken brain or the egg size.

speaker-1 (01:08:31.694)
Question. But yeah, so many aspects of growth to consider. So that wraps up this episode of Ino Dino. Stay tuned. Our next episode of Inodino will be talking about a number of new dinosaurs. If you want even more dinosaur goodness, we have our bonus episodes that go in between our regular Ino Dino episodes, and you can listen to those at patreon.com slash InoDino. Thanks again, and until next time.

(Approximate times)

• 00:00 Introduction to Dinosaur Discoveries and Exhibits
• 02:59 New Sauropodomorph Xiang Yun Long Feng Ming
• 08:58 The Six Extinctions Exhibit at the Bruce Museum
• 10:03 Mass Extinctions and Human Impact on Biodiversity
• 11:01 Fossil Birds and the Extinction of the Chatham Islands Penguin
• 11:58 Fossil Critters and the Diversity of Extinct Animals
• 12:54 The Triassic Mass Extinction and Dinosaur Evolution
• 13:48 Fossil Discoveries in Connecticut and Local Paleontology
• 15:04 T-Rex vs. Taurosaurus: The Ongoing Debate
• 15:52 The Evolution of Bird Brain Size and Cognitive Abilities
• 17:13 Fossil Evidence of Dinosaur Social and Parental Behaviors
• 17:58 The Record-Breaking Pelagornis Sandersi and Its Unique Features
• 18:46 Feeding Strategies of Ancient Flying Birds
• 20:12 The Fascinating World of Fossil Birds and Their Adaptations
• 20:46 The Ecological Roles of Juvenile and Adult Dinosaurs
• 22:13 Implications of Dinosaur Growth and Development Studies
• 22:50 Museum Exhibits and Art-Science Intersections at the Bruce Museum
• 24:07 Conservation Lessons from Extinct Species and Modern Biodiversity
• 24:55 How Paleontology Informs Our Understanding of Earth’s History

Summary

Join us as we explore the fascinating world of dinosaurs, fossil birds, and mass extinctions with Dr. Daniel Sepka. Discover the latest discoveries, research, and exhibits that shed light on Earth’s history and the evolution of life.

Takeaways

• Xiang Yun Long Feng Ming sauropodomorph discovery
• Dinosaur naming and etymology
• Mass extinctions and their impact on life
• Bird evolution and brain size studies
• Fossil bird research and fossilization processes
• The debate over Taurosaurus vs. Triceratops
• The role of juvenile dinosaurs in ecosystems
• The significance of the Triassic mass extinction
• Museum exhibits blending art and science
• Conservation lessons from extinct species

Keywords

Dinosaurs, Fossil Birds, Mass Extinctions, Paleontology, Evolution, Bruce Museum, Scientific Research, Dinosaur Names, Extinction Events

Hello and welcome to I know Dino. Keep up with the latest dinosaur discoveries and science with us. I’m and today in our 570th episode.

speaker-1 (00:36.942)
And I’m Sabrina.

We’ve got a new sauropodomorph with a sturdy long tail.

speaker-0 (00:45.294)
That’s how I like I want those flimsy tails, a nice sturdy tail. I don’t know. It’s it’s got the lengths at least.

speaker-1 (00:49.818)
You don’t like diploticates?

speaker-1 (00:54.286)
We also have an interview with Daniel Sepka, curator of science at the Bruce Museum in Connecticut. And he is an expert in fossil birds. We talk about all kinds of things. And we have Dinosaur of the Day, Brazillo Titan, a square jawed titanosaur. Mm-hmm. That’ll sauropod theme going here. And our fun fact is that dinosaurs were latchkey kids, and mammal parents were or are more like.

Helicopter parents.

speaker-0 (01:24.27)
That’s true. All the helicopter parents I know are mammals.

speaker-1 (01:28.308)
Good one.

speaker-2 (01:31.278)
But

speaker-0 (01:31.95)
But before we get into all of that, as always, we’d like to thank some of our patrons for helping to keep us going. And this week we have 10 random drawing winner patrons to thank, as usual. They are James Pasco, Tyrant King, Daniel McGill, Quadrasaurus, Jennifer, E Ray, Scott, and Lorasaurus. And if you joined recently, we’ll be thanking you soon. But we had to pre record some episodes because we had to do some last minute travel.

speaker-2 (01:43.907)
David?

speaker-1 (01:47.166)
K

speaker-1 (02:01.42)
Yes, so thank you for your patience and thank you to all of our Dino Itals. We hope you are enjoying this show because you make it possible, as well as the perks that you get from Patreon, which includes this month, if you pledge for our dinosaur rookie trading cards, you can get an extra special exclusive nano tyrannus card. Mm-hmm. You just you do have to pledge for the cards.

speaker-0 (02:22.936)
But no extra cost?

speaker-0 (02:27.672)
Yeah. That we’ll just throw it in with the other cards. Will we mail them to you?

speaker-1 (02:31.266)
Yes, and we have about a week left for that campaign. So that means time is running out if you want those trading cards or the stickers or the keychains or our enamel pin or magnets. Yeah. Now is the time. Mm-hmm. Yes. So head over to InoDino.com slash cards if you wanna make sure you get your cards. Jumping into the news.

speaker-0 (02:44.066)
Magnets.

speaker-0 (02:48.354)
It ends at the end of July.

speaker-1 (02:59.736)
There’s a new sauropodomorph dinosaur, Xiang Yun Long Feng Ming, that had a sturdy long tail. This was published by Royal Society of Open Science, it’s open access, by Xiaobin Hu and others. And this sauropodomorph lived in the early Jurassic in what is now Yunnan China. It was found in the Feng Jiahu Formation. They found a partial skeleton that includes neck, back, and tailbones, parts of the ribs, and parts of the hips. So they found 15 tailbones, five backbones, and three neck bones, if you want to get specific.

And the neck bones are short, especially compared to other sauropods. Xiang Yunlong is estimated to be thirty to thirty-three feet or nine to ten meters long, and it’s one of the largest known early diverging sauropodomorphs from China. That’s a mouthful.

speaker-0 (03:45.95)
It is. So of all the early Jurassic and late Triassic sauropodomorphs in China, it’s one of the bigger ones. At thirty feet, that is pretty big.

speaker-1 (03:57.366)
Yeah. So it didn’t have a particularly long neck because its neck bones were on the shorter side, but it did have a robust long tail.

speaker-0 (04:05.206)
That’s where the action is.

speaker-1 (04:06.784)
It might yeah, that tail might have helped it with balance. It might have helped it rear up to eat.

speaker-0 (04:11.084)
It reminds me of another thirty foot long animal with a robust tail. Ankylosaurus. It’s funny to think that the sauropodomorph was about the same length as Ankylosaurus. Yes. I’m guessing Ankylosaurus’ tail was more robust.

speaker-1 (04:15.97)
Which one?

speaker-1 (04:27.5)
Well, yes. I don’t think there’s much guessing there. But back to the sauropodomorph. This helps show s more diversity in sauropodomorphs before they evolved into the long necked giant sauropods, ’cause the long tail may indicate an initial stage of gigantism, and it could be another evolutionary pathway to getting big.

speaker-0 (04:48.792)
Yeah, it’s interesting to hear the tail getting longer first, ’cause I feel like we’ve seen other ones that had a longer neck. That’s

speaker-1 (04:54.124)
Yeah. That’s the usual route, at least the ones we’ve found so far. So the genus name Xiang Yu Long means auspicious cloud dragon. Nice. Auspicious means promising or favorable. It refers to the county where it was found, Xiang Yun, and that name means auspicious clouds. And then Long means dragon.

speaker-0 (05:13.26)
And they use the less common spelling of long with two o s.

speaker-1 (05:17.218)
Yes. And then the species name, Feng Ming, means Phoenix calling. It refers to Luming, the town where the fossils were found, which also means deer calling, and it’s a reminder that birds are living dinosaurs. It’s doing double duty here.

speaker-0 (05:32.43)
Nice. I like that they got a little creative with the name.

speaker-1 (05:35.906)
Names. Yes. And Feng Ming is also the original name of Lin Feng Min, the founding president of China Academy of Art and staff of China Academy of Art helped a lot with this project.

speaker-0 (05:46.392)
Double whammy, so many double meanings going on. They really got their money’s worth out of that dinosaur genus and species name.

speaker-1 (05:53.366)
Yes. And it’s a place name, but also more.

speaker-0 (05:59.958)
And in just a moment we’ll get into our interview with Daniel Sepka, but first we’re gonna pause for a quick sponsor break.

And now onto our interview with Daniel Sepka. But as always, we have an extended version of our interview for those who want to hear even more about what we got to talking about. And you can get that at patreon.com slash inodino or in the Apple Podcast Premium. And if you listen there, there’s a timestamp in the description where you can jump ahead to after this shorter version of the interview. So without further ado, on to our interview.

speaker-2 (08:44.664)
Feed.

speaker-1 (08:58.19)
We are joined today with Dr. Daniel Sefka, a vertebrate paleontologist who specializes in birds, which of course are living dinosaurs. He has more than 70 peer-reviewed research papers and many articles for publications, including Scientific American and American scientists. His main research is on penguins, though he has studied everything from turkeys to albatrosses. He’s also a research associate at the American Museum of Natural History and the Field Museum of Natural History.

adjunct faculty member at the University of Connecticut and Curator of Science at the Bruce Museum in Connecticut, which is an art and science museum, and they’ve got an exciting exhibit out right now about Earth’s mass extinctions. So thank you so much for chatting with me today.

speaker-2 (09:39.886)
Thanks, Sabrina, really happy to be here.

speaker-1 (09:41.57)
Yeah, I wanted to ask first, can you tell us about the Six Extinctions exhibit?

speaker-2 (09:47.276)
Yeah, this is a really fun show. We have everything from Tyrannosaurus to some giant molluscs. And so as the title implies, it covers all of the major mass extinctions in Earth history, the big five in geological time, and the one that we’re unfortunately causing right now.

speaker-1 (10:03.054)
I was gonna ask, yeah, because that one I is there some debate about the sixth extinction if we’re going through it or if it’s we’re not entirely sure.

speaker-2 (10:10.604)
I think it’s really pretty well established that we’ve elevated the extinction rate far above the background with our own activities. Basically anywhere where humans have have gotten, they’ve caused a lot of trouble, especially on islands. That’s from my perspective as a bird paleontologist. We all know about the dodo, but there are dozens of other species that have been wiped out around the world. Whenever people kind of got around and either were collecting the birds directly for food or for eggs or for meat, or

Altering the environment. So introducing other species, changing habitats. We’ve done some damage, unfortunately.

speaker-1 (10:45.354)
Right. It’s not been great for penguins, right.

speaker-2 (10:48.024)
Penguins it always surprised me how well penguins seem to have have done over the years as flightless birds. But we now know that there’s at least one species that was wiped out by humans a little more than like six hundred years ago.

speaker-1 (11:01.92)
that’s pretty recent.

speaker-2 (11:03.434)
It is, yeah. It’s a a species of penguin that was on the Chatham Islands. My colleague Tess Cole led a study that I was part of where we actually had ancient DNA from these bones that were found in like sand dunes out on the Chathams, and they showed that there was a crested penguin species that was basically wiped out pretty quickly after humans got out there.

speaker-1 (11:22.018)
Wow. Does that make an appearance in Six Extinctions?

speaker-2 (11:25.366)
That one does not, no, unfortunately. It did make an appearance in our exhibit Penguins Past and Present, which we did in twenty twenty three, which was about penguins today and and their their evolutionary history.

speaker-1 (11:36.28)
So six extinctions read in the press release you’ve got fossils, there’s casts, there’s realistic models and murals. What sort of animals can people expect to see?

speaker-2 (11:47.64)
There’s a lot of fun critters there. One of my favorites is Anthroplora. This is basically a giant millipede. And so you’ve got this thing that kind of looks like maybe an area carpet that came to life. It’s truly delightful and gruesome. And it it’s you know, it is related to modern millipedes. And so it’s probably like them eating like plant matter and decaying stuff. And so it wouldn’t necessarily be a terrifying creature to us, but it was it was really a fun animal. So that’s one of my faves.

speaker-1 (11:58.102)
Okay.

speaker-2 (12:15.724)
That’s a life reconstruction, so it’s got, you know, the appearance it would have in when it was alive, which was, you know, roughly three hundred million years ago. Yeah, nothing more fun than a nine foot millipede. I spent so much time looking under rocks and logs with my kids and we haven’t found that one yet, but classic.

speaker-1 (12:30.638)
And I said it’s not really a threat to us, but I can imagine standing next to it, it might still seem a little scary.

speaker-2 (12:38.542)
I think the worst thing would be if you accidentally stepped on it.

speaker-1 (12:41.486)
Do you have a favorite mass extinction?

speaker-2 (12:45.912)
Favorite mass extinction. Hmm. It it almost makes you feel bad, right? But

speaker-1 (12:49.634)
Yeah, is that a too too depressing of a question?

speaker-2 (12:54.144)
I I kind of like the Triassic mass extinction and there’s two reasons. One is that it it gives the dinosaurs like the leg up they need to to really take over. And I I love dinosaurs. I mean I think everyone does. And so they may never have achieved the the great sizes and wild forms they did if it wasn’t for you know, removing the boot of the crocodilomorphs from their neck. And that is also really cool to me because it kind of took place like right where we live, Connecticut.

The middle of Connecticut, that fertile valley, the Connecticut River Valley, that’s basically a former lake. the continents started breaking apart. And that rift zone, if it would have continued, that would be the Atlantic Ocean. Eventually it stopped spreading there and started spreading farther east. And so the Atlantic is is still rifting today, but we had a kind of failed tear, and that filled in with these lakes. That’s where all the dinosaur footprints are, these wild fish that we we have, many of them in our collection thanks to Nicholas McDonald.

And massive outpourings of of lava and magma. And this this is really the driver of this extinction. And it’s represented in our landscapes. Like we’ll be driving through these, you know, beautiful less urban parts of Connecticut and you’ll see these rock formations. And that’s basically the volcanic eruptions that wiped out all those creatures. so you’re you’re kind of living right there. And that’s that’s why it appeals to me as a Connecticut resident.

speaker-1 (14:12.334)
That’s cool. Yeah, I ’cause I I don’t think we talk about Connecticut too often when we’re talking about but Yeah. You’ve got some great museums.

speaker-2 (14:23.148)
We have some wonderful museums. I mean, the Bruce, of course, we have our friends at the Peabody. And there were a lot of cool Triassic creatures historically discovered here. It’s tailed off a little bit and that’s because we used to really mine these rocks, these Triassic and Jurassic rocks for construction, like all these brownstones in New York City. A lot of them are made with rocks taken out of Connecticut. but we’ve switched, you know, no one’s really building with those materials anymore. Now we’re using steel and all these other things. But

Back when they were quarrying we’d find fossils a lot more. Now you’re only seeing what erosion reveals or the occasional roadcut. So there’s just not enough excavation going on to turn up these nice skeletons that we once were were getting relatively frequently.

speaker-1 (15:04.302)
Yeah. Well, okay, going back to the Six Extinctions exhibition, I thought it was interesting that there’s a face-to-face encounter with a T-Rex and Taurosaurus at the end. It sounds like the Bruce Museum is team Taurosaurus.

speaker-2 (15:19.456)
are we? Why is that?

speaker-1 (15:21.72)
I usually hear T Rex versus triceratops, right?

speaker-2 (15:24.526)
sorry, thought you meant we were rooting for one versus the other. Well, Taurus Taurus is is an interesting question, right? So I don’t know if you’ve had have you had a Triceratops Taurusaurus episode? Yeah. So I’d encourage people to listen. That I won’t go into it too much detail, but I actually have friends on both sides of the debate. So I don’t want to come down obviously in favor of one or the other, but but basically the debate is Triceratops is iconic dinosaurs probably one of the three dinosaurs that people name if you say name three. Mm-hmm.

They’re probably gonna say Stegosaurus, Triceratops, Tyrannosaurus Rex. And it’s this, you know, beautiful three horned animal. Taurosaurus looks very similar, but it has big holes in the frill, which triceratops doesn’t have. And so there’s this debate whether they’re two separate species or whether Taurosaurus is actually like an old triceratops. It’s it’s gotten to full size and then it’s developed in these openings. And it’s a really tricky debate. We can’t really ever be a hundred percent sure. we’re never going to be able to like DNA test them or observe them in the wild, but

We are going with Taurosaurus here in the exhibition. And I think that’s the favorite hypothesis of the people who have the original at Yale. So but but it is it’s an ongoing area of research. There’s a lot of a lot of evidence kind of in favor of both sides. And so I don’t know if we’ll ever be a hundred percent sure.

speaker-1 (16:40.802)
Yeah. Just need to find that one skeleton.

speaker-2 (16:44.746)
Well, you know what you’d want to find, I think, is in theory, if Taurusaurus is an old triceratops, those holes are opening up as it ages. But I don’t think they’ve ever found like a triceratops with like a tiny opening in the frill and then one with half of an open. That’s what we’d really want. And maybe that’s something that took place over the course of a year as the dinosaur hit maturity or something, and so we never got one. One of the reasons I I kind of favor the Taurus is there’s really a lot of triceratops out there, and so it would be a little weird if we’re finding a

So many young ones and very few old ones. now it could be that the adults go live in a different area or something like that, but I’d lean towards Taurosaurus, I think.

speaker-1 (17:22.882)
Yeah.

speaker-2 (17:26.038)
No disrespect to anyone who’s doing the work. I’m a bird person, so this is just kind of me glossing over the literature.

speaker-1 (17:31.938)
Yeah. Well, I know you’re a world expert on fossil birds. And actually this was good timing. I recently read a bit about you in Steve Brussati’s latest book, The Story of Birds.

speaker-2 (17:45.375)
no. So I I I keep hearing this from friends and family. I ordered my c I haven’t received it yet. So I have no idea what it says, but hopefully it’s good.

speaker-1 (17:53.656)
Good things, yes, you you come off very impressive. World expert on birds, on fossil birds. Get assigned one.

speaker-2 (17:58.591)
wow. Well that’s that’s kind. I mean I should buy two copies. Maybe.

Yeah. that would be easy well I gotta go to Scotland now though.

speaker-1 (18:07.342)
I know you described as Pelagornous Sandersai.

speaker-2 (18:12.502)
Yes, yes, that’s a big one.

speaker-1 (18:14.158)
It’s got like the what the widest wingspan of any known bird.

speaker-2 (18:17.578)
It does. So it was this huge creature that hilariously enough was actually found at the Charleston Airport. Which I always I always laugh about. It’s so it’s, you know, a little close to twenty five million years old. And it had a wingspan roughly around twenty feet, which is really impressive. Basically when I try to describe it, I say you could take like two California condors and tape them together and this thing would still have a bigger wingspan. So absolutely massive compared to anything alive today. And

Honestly, totally bizarre beyond that. So the size is almost like the most normal thing about this bird. It’s huge, but it’s also got teeth. So it’s got pseudo-teeth, bony teeth. It it looks like it’s got like this, you know, pumpkin jack-o’-lantern grin, but all these sharp little cone-like structures, and they’re actually not true teeth. They’re made of bone. So they’re not enamel and dentine, they’re not in sockets, they don’t replace themselves. They’re they’re projections of the premaxil and the mandible.

They probably would have been covered with beak tissue in life. They said it would have been sharp, but they would have had like a little coating because you can see like the blood vessel traces on the surface. So they had to have something over them. And the bird is it’s got like a hilariously tiny shoulder bone, like the scapula shoulder blade. In fact, when I submitted the paper to Nature, it got rejected. And one of the reviewers said, Clearly I’ve mismatched this bone and it didn’t belong to the specimen because it was too small. But they they have articulated smaller ones.

probably couldn’t really raise its wing above above horizontal. So it it looks like it was hyper adapted to gliding. So very good at holding its wing stretched out, but not very good at flapping. And and maybe it even needed some type of assistance from the wind or you know, jumping off the proverbial cliff as a reviewer said to get into the air. so weird and I sort of hinge draws. There’s three hinges in the draw the d the drawbone’s actually in three separate pieces with a synovial joint, which is like, you know, like a

little capsule joint like your knee or something. And so it probably could expand its jaw like almost it’s so flexible. The only thing I can think of that’s really similar is like snakes. Wow. and it wasn’t it wouldn’t be that crazy, but like a ridiculously flexible jaw as well. And so so many oddities in one creature. And it also happens to be the record breaker for wingspan. Probably not the heaviest bird ’cause its bones were like paper thin. But but in terms of that span, just breathtaking.

speaker-1 (20:41.55)
Do you think it’s just like gliding along with its jaws open? Or maybe

speaker-2 (20:46.134)
It’s very d yeah, we’re really debating what on earth it ate, right? So it’s its legs are dinky. So I think, you know, an albatross can actually get down like you know I think some of them go like six meters down in the water, which is surprising because they have really wide wingspans. And so a lot of seabirds will, you know, there’s gannets that plunge dive and they’ll actually basically fall from the sky and catch fish that are below the surface. There’s skimmers, which, you know, the black skimmer, which is the you can find that on the east coast, it will skim

Like just dip its mandible as it goes. But it it I don’t think that’s any of those are really viable for something so large. There actually was a study recently, a biomechanical study, that said the drag would be too great if it tried this game. So it it almost has to feed at the surface of the water. And the only thing we can really think of is like flying squid and flying fish. And so it’s a it’s gotta be snatching things near or even above the surface. And that that kind of blows my mind because how many patches of flying squid are there?

The the other thing I propose in in the original paper is that it can also eat kinda anything it wanted on land and so there’s this horrifying picture that’s circulating online, but it’s a it’s a pelican eating a pigeon. You know, pelicans and and albatrosses as good as they’ll raid other birds’ nests. They’ll eat the eggs, they’ll eat the chicks. And so I would imagine like a Pelagornus would probably be pretty happy to come to like a gull or albatross or whatever breeding colony and kind of just

What are you gonna do to a bird with twenty foot wingspan? It would just take whatever it wanted. So that was probably a very important food source for it as well.

speaker-1 (22:21.152)
That is a weird bird.

speaker-2 (22:22.958)
It’s so weird. I key I visit Charleston like every two years I go back because there’s something else I need to look at about. I’m like, I forgot to look at this. I forgot to look and it I always find something new on the same skeleton. It’s just such a it’s so bizarre. There’s nothing like it today. I mean, you know, there’s fossil penguins and they’re basically just really big penguins or penguins with long beaks, but there’s no analog there’s no toothed bird alive today to compare this to. There’s nothing that’s that big. And so you’re kind of

Doing your best to to speculate. And if you if you can, you can test it with some kind of models. But I don’t know, sometimes like, you know, the wind tunnels where science goes to die. You’re making a lot of assumptions, right? I’m sure whatever it we think it did, it would shock us to just put on the time travel binoculars and see what it was up to in real life.

speaker-1 (23:10.7)
Yeah. Yeah. You could say that about pretty much anything, right?

speaker-2 (23:14.814)
yeah, I mean all these like what blows my mind about dinosaurs and I I’ve o I did work on one sauropod or Keycha when I was in grad school. I they’re always made my favorite. The Bronosaurus I I don’t I know for great. Yeah. I I it’s good good good taste. I know there’s some debate over whether Bronosaurus is a valid genus, but I’m gonna roll with it. And that was always my favorite. So working on one when I was in grad school is great, but what

What’s up with them, right? Like their heads are like the it’s like the size of a horse’s head and the body’s like fifty tons or more. Like, how did they work? Did they have like, you know, like a brewery in their stomach or they’re fermenting? I mean, even if they’re doing that, you’d think they’d have a larger mouth. They they just they completely k baffle me. Like as something that needs to eat enough to live. I just I can’t wrap my head around it.

speaker-1 (24:07.8)
Yeah.

speaker-2 (24:08.728)
They’re so weird. They’re just so and they’re like filled with air. Yes. And their necks are like I mean, did they just stand there like a vacuum cleaner and move their neck? How did they get through a forest without knocking everything over? Right. How did they even like lay their eggs without them just like falling to the ground and shattering? It everything about them is fascinating to me.

speaker-1 (24:26.39)
Yeah, same. Plus I I was a fan of Littlefoot.

speaker-2 (24:32.112)
yeah, that’s a popular I think that got a lot of people into this Team Sour Pot.

speaker-1 (24:36.43)
I think so too. Well, on back to the birds. I know you led a major study of reconstructing the evolution of bird brain size.

speaker-2 (24:48.299)
yeah, yeah, that was fun.

speaker-1 (24:49.614)
And actually I think that that was probably a little bit in Steve’s book too.

speaker-2 (24:55.892)
yeah. So that was a great great project. It was at Nescent, which was a evolutionary synthesis center in Durham, North Carolina. And they had a program called catalysis meetings where you basically can bring scientists from different fields into one room to solve a problem. So our meeting was about bird brain evolution, and we had people who are like computer statisticians. We had people who do evolutionary trees, people who put little PET helmets on birds to see where what they’re thinking when they’re flying.

People who look at fossil brains to understand like how Archaeopteryx worked, CT scans, MR like every different type of gene labeling, vocalization in hummingbirds, like every topic you could think of, putting them all in one it’s so great because no one can be an expert on it. So everyone learned something. And we had this like I think it had like thirty two authors, and that was one of the biggest tests of my career was getting like thirty two people to send their data into the same spreadsheet.

speaker-1 (25:51.788)
Ha ha.

speaker-2 (25:52.492)
But I think we learned a lot about, yeah, how bird brain size changed over time and the dinosaur to bird transition and then equally important like among different types of living birds.

speaker-1 (26:02.69)
Yeah. And so what was the trend? It got smaller but denser?

speaker-2 (26:08.15)
One of the funny things is you you always think of dinosaurs I think especially like before Jurassic Park, everyone thought of them as pretty dull witted. I think after Jurassic Park, maybe people think they’re too smart. It kinda like it kind of went into overdrive. We’re like, well, we all know dinosaurs communicated with language and use tools. And it’s like Yeah. so I think that the smartest so the smartest dinosaur was probably about as smart as the dumbest bird is a simple way to put it. There’s not a big

speaker-1 (26:24.078)
Glossaraptors, they can do anything.

speaker-2 (26:35.688)
change in the brain-body relationship. And so we’re looking at not raw brain size, because obviously like an elephant should have a much bigger brain than a mouse, but it scales not isometrically. And so as you get bigger, you need a proportionally smaller brain because some of your brains just like remember to breathe, remember to breathe, remember to breathe. And so like a mouse scaled up to an elephant would have like a huge brain. It would look like this like, you know, alien. But that’s not true because it’s there’s a different slope. Anyway, a lot of

of the first birds to branch off, the bird tree, and dinosaurs kind of pr they’ve kind of fall out on the same line. And so we think that some t theropods were probably like similar in cognitive ability. And and this is of course tricky ’cause not every part of the brain does the same thing, right? Like you can have a a large brain because you have a big olfactory boom and that just means you can sniff really well. But all things being equal, I think those advanced dinosaurs were like in the early bird zone. There’s not like a big change when flight evolves or anything like that. That’s kind of cool.

And then you see some some trends towards really profound brain expansion in groups like parrots and then Corvid. So crows and ravens, they’re like we we had tried to come up with an analogy and we kinda said they’re like the hominids of the bird world. So like these birds, they got bigger and their brains got bigger at the same time, but but faster than their bodies. So like us, we’re scaling up from early primates. And so like, you know, you have Lucy and she’s pretty short.

And then you get bigger and bigger towards like humans, sort of anatomically modern humans, and the brains also skyrocketing at the same time, but it’s it’s going even faster. And so you end up with a bigger body, a bigger brain, but it the brain’s even proportionally larger. And that’s what’s happening in like frozen ravens. So they’re kind of near the the pinnacle of the bird world, them and parrots really. Other groups, you know, they don’t seem like they need a large brain, like pigeons. I I really like pigeons. A lot of people are grossed out by pigeons.

They’re amazingly good at maneuvering in the sky. Like they can some they they really can do some interesting, you know, turning on a on a dime. But pretty sure I saw a pigeon eat a cigarette in New York. So so like the dodo, for example, it’s portrayed as like this, you know, dopey bird. It’s it’s really just a big pigeon. It’s not that the dodo has a tiny brain. It’s that th that whole group is pretty small brain compared to their body side, and that’s just a really big one. Yeah. So

speaker-2 (28:54.36)
Yeah, different different needs though, right? You know, if you don’t need a to do doing, you know, trigonometry, mm-hmm. You don’t really want your brain to be very big ’cause it takes a lot of energy. It’s the most expensive tissue. Like the most expensive organ is the brain per like, you know, cubic centimeter. So having a huge brain and not using it is is an evolutionary liability.

speaker-1 (29:14.37)
Yeah, that makes sense.

speaker-2 (29:16.322)
Yeah, T Rex was a very smart. My my friend Amy Balanoff and I had an article in Scientific American. We we read this paper that said like T Rex had baboon like cognition. We were like so outraged, we’re like, we’re gonna write a reply. And we start we wrote like half the paper, and then Amy got like a like a Google Scholar notification that someone else had already published the thing. But we rolled it into the Scientific American paper, which was kind of more on the whole way T Rex perceived the world. So we

speaker-1 (29:26.284)
That paper, yeah.

speaker-2 (29:44.13)
We still got to use our our research, but we were like, No way, ’cause it’s not very big and half of it’s just for smelling and like a lot of it’s empty too, like a dinosaur brain case for a T Rex. Part of it’s just like blood vessels and junk and sinuses. So there we don’t think it was super smart.

speaker-1 (29:59.47)
It didn’t need to, it had the powerful bite and then

speaker-2 (30:04.332)
Yeah, it just needed to see you or smell you and then go eat eat you. So it did I don’t think it I don’t it never I don’t I doubt it came up with like a plan of attack where we’re gonna you know, we’re gonna come in from the left and then, you know, they’ll fall into a pit we dug. It was sh I’m gonna go eat that guy.

speaker-1 (30:18.83)
Yeah. Do you think any dinosaurs had coordinated a an atta and I know that’s a big question because then there’s a lot of debates but

speaker-2 (30:27.978)
Yeah. Well, so we know there’s some pretty complex behavior in dinosaurs from from direct fossil evidence. So we have like nesting dinosaurs, right? So Ovaraptor and Truodontids, they they clearly incubated their eggs or at least brooded their eggs. And so they they probably have partial contact incubation. So that’s showing a level of care. We have evidence of like satakosaurs living in like groups and like in the burrows and things like that. So there’s definitely some some social behavior, some parental care.

The whole pack hunting thing’s really hard to prove. Yeah. I don’t know w what kind of preservation environment you’d have to get to to have that. but I I think, you know, we look at things that ostriches and emus and chickens do. Dinosaurs are probably capable of very similar things. And so, like, you know, ducks shooing their their young out of the nest into the water or

Teach you know, nudging them to fly and things like that. That’s probably all within their behavioral capacity.

speaker-1 (31:29.026)
Yeah. I mean I’d like to think that there were some pack hunters, but

speaker-2 (31:32.682)
It probably makes sense for some of the smaller ones, especially. I think the Deinonychus, you know, feeding on Tenantosaurus is probably the best example we have. And it’s not like smoking gun exactly, but it probably they’d have a better chance, I think, tanking one down together. Mm-hmm.

speaker-1 (31:49.55)
Is there anything else that we haven’t talked about that any like research you’re working on or we could go back to exhibitions, things you want to mention?

speaker-2 (32:00.364)
Yeah, just really want to encourage people if you’re in the Connecticut or New York City area to come see Six Extinctions. We got Scotty. So the T Rex is a cast of Scotty, which is nice. One of the largest T Rex ever discovered. Interestingly, discovered by a high school principal, which is great. and it was in like this crazy sedimentary environment. So it took I think like twenty years or something to fully remove it and reassemble it. So it was a lot of work, but it’s a a beautiful skeleton.

About forty feet long, I believe. Estimated at six tons. So it’s an impressive animal. And that’s what’s kind of great about T Rex is it used to just be there’s a Tyrannoshirus Rex. Now they all have names. Yeah. There’s like Sue and Scotty and whatever. And it’s facing down that that Taurosaurus, that controversial serotonin.

speaker-1 (32:44.726)
that’s where Scotty is. Nice.

speaker-2 (32:46.7)
We have them kind of staring each other down. So that’s that’s a highlight I think for most people. Everyone loves sinosaurs. But what’s really fun is delving into the others. So see the giant nine foot millipede and and see and we have classics like the Metrodon, the sail back the reptile. We have that that squidded and ice cream cone we were talking about before. and then there’s animals from the most recent extinction. So we have woolly mammoths and sabretooths that were wiped out basically when humans were moving into the Americas.

And also we have a few objects from our own collection, examples of birds that were wiped out in the last century. So like passenger pigeons, Carolina parakeet, Heath and you know, really sad stories. These two species, passenger pigeon and the Carolina parakeet, the last one died in the Cincinnati Zoo both times. I mean, that’s just it was Inca, I believe, was the name of the parakeet, and Martha was the pigeon. Martha’s in the Smithsonian actually, they had her on display on the hundredth anniversary of of the extinction, but

It’s such a cautionary tale, right? There were in Autobahn’s day, there were flocks. They said flocks would take hours to pass over you. Like, could possibly a billion birds like moving in in unit? I mean, just unthinkable numbers, like so so abundant it almost defies belief. It’s almost like it’s a plague of locusts. And and then they’re gone in like a blink of an eye. And so they really they seem absolutely limitless. And now there’s none left.

The Heath end, that died out on Martha’s Vineyard. The last one was called Booming Ben. And you think of these events as happening in the past, but he was he died near an airport on Martha’s Vineyard. So like it was not that long ago. and it’s just they were once allegedly so common that people would complain if they had to be f serve them more than three times a week. I mean, they were supposedly in the common in Boston. so they it’s

Really eye opening house, something that we we just take for granted that is like, you know, it’s just there and it can it can be gone really quickly if we if we are careless with it.

speaker-1 (34:50.414)
Definitely. So for our listeners, if they want to know more about the Bruce Museum or you and your work, are there places they can go online?

speaker-2 (34:57.868)
Yeah, absolutely. So we have a website, of course. You come to the Bruce Museum website, Bruce Museum.org, you’ll see all the exhibitions we have. And we are art and science, right? So we have Six Extinctions is really fun because we actually have a T Rex in a gallery that usually has art in it. But we’re gonna have a great show from Sergeant to O’Keefe with these these masterpieces of art in that same space in in the October. And so like there’s not many museums in the world where you can go see like a Pizarro.

A 2,000 pound quartz crystal, a Dilophosaurus model, a living turtle, and you know, a bunch of Giacometti sculptures. Like we have so much. I’m on the science side, obviously, but it’s really great to be able to enjoy all the art. And one of the things we really pride ourselves on is finding those intersections between art and science. And so we often have, you know, sculpture that’s inspired by natural objects right next to the mineral gallery. We had this beautiful Tara Donovan piece, and it looked

For all the world, like a giant piece of scolocyte, this zeolite mineral. in fact I heard many dads tell their kids it was a giant crystal. it was called aggregations, but having those side by side is just so so eye-opening and evocative and fun. We had this fun art show with Jennifer Angus. she actually covered the walls of our art gallery with over four thousand insects. So they were pinned in these wonderful Victorian patterns, and there was these little vignettes of bugs baptizing one another and coronations and

playing dice and all these things. And so that was like it’s an art show, but it’s the substrate is or the the medium is not paint or or clay. It’s it’s insect. And so that’s what makes us unique, right? We’re not the biggest museum in the world, but there’s so few that that would have both of these. And we’re so proud of that and and really finding the the times when we can do both at once is what what we really live for.

speaker-1 (36:49.134)
Amazing. Well, thank you so much for so for our listeners, you have until September sixth if you want to see six extinctions, although it sounds like there’s never a bad time to visit the Bruce Museum.

speaker-2 (37:01.202)
The only bad time is Monday. We’re close Monday. But other than that, come on come on in. yeah, I I can’t recommend it enough. It’s a it’s a terrific show and you know, come for the dinosaurs, stay for the millibeat.

speaker-1 (37:11.886)
And we also have a on our Patreon we have a whole series on mass extinctions too. If anyone wants to listen more and, you know, bone up on that before you see the six extinction exhibit. So thank you so much for taking the time to talk with me today.

speaker-2 (37:28.462)
Thanks, Sabrina. I had a had a blast. Thank you so much.

speaker-1 (37:31.662)
Thank you so much, Daniel. That was a lot of fun talking about the Six Extinctions exhibit, as well as birds, of course, and especially penguins. Love talking about penguins. And we will get to our dinosaur of the day in just a moment, but first we’re going to take a quick break for our sponsors.

speaker-1 (39:19.534)
And now onto our dinosaur of the day, Brazillotitan, which was a request from Dilophosaurab via our Patreon and Discord. So thanks. It’s great. So Brazillotitan was a titanosaur sauropod that lived in the Lake Cretaceous and what is now Brazil, in the Adamantina formation. It was small, it walked on all fours. It had a long neck and a long tail and a small head. As a titanosaur would have walked with its neck more upright. And by small I mean it’s estimated to be

speaker-0 (39:26.636)
I love the Dilophyso Rob.

speaker-1 (39:47.97)
39 feet or 12 meters long. It had a squared off snout. The lower jawbone was L-shaped, so that gave it the squared snout. You can think like Nigerosaurus, but much less extreme. The type and only species is Brazillotitan nemophagus. The genus name Brazilotitan means Brazil giant, and then the species name means pasture or wood and to eat and refers to it being an herbivore. The fossils were found in 2000. They were found in reddish sandstone.

Bones were broken, but not really distorted. And then Brazilotitan was described in 2013 by Elaine Machado and others. And the holotype’s a partial skeleton and includes a right lower jawbone, two partial neck bones, parts of the hips, and a footbone. They also found an isolated tooth. It’s likely that Brazil titan was scavenged by theropods before it was buried, because there were some theropod teeth found alongside the skeleton, and the fossils have puncture marks, and they’re in the hips.

speaker-0 (40:44.55)
yeah. Something that you might not reach if you’re just happened to be biting an animal. That’s more of a consuming sort of

speaker-1 (40:52.984)
Happen to be biting. Yeah. Some other dinosaurs that lived around the same time and place as Brazilla Titan include sauropods such as Antarctosaurus and Gondwana Titan, and theropods such as abellosaurs and enantiornithes like Navaornis. Other animals that lived around the same time and place include amphibians, turtles, fish, mammals, and crocodilomorphs. And our fun fact is dinosaurs were like.

I’m saying this in quotes latchkey kids, and then mammal parents were or are more like in quotes helicopter parents. This is from something that Thomas Holtz Jr. wrote in the Italian Journal of Geosciences. So dinosaurs in the Mesozoic and mammals today are often considered to be ecologically equivalent. They are or were the majority of the medium and large animals in their eras.

speaker-0 (41:46.934)
In other words, the Mesozoic was the age of the dinosaurs and the Cenozoic is the age of mammals.

speaker-1 (41:54.24)
Exactly. There’s also similarities between dinosaurs and mammals in terms of posture. The fact that we and they, because we’re mammals, we and they have different ways of eating. And there’s evidence of some levels of being warm-blooded. Well, we know that with mammals, but with dinosaurs. But how similar were they really in terms of ecology and meaning how they interacted with their environment? And it turns out that there’s a big difference between mammals and dinosaurs.

And how animals raise their young impacts the ecosystem around them. So with mammals, young animals usually stay close to the mother until they’re nearly fully grown. And that means that they fill the same ecological role as their parents. They’re relying on adults for food and protection and they’re interacting with the same surroundings. And that’s what makes mammals the helicopter parents. Young dinosaurs, on the other hand, were pretty independent. Some had parental care for a few months or a year, but then some of them took care of themselves right away.

And that’s what makes them the latchkey kids. And they’re independent. They could also being independent spread into niches that their parents weren’t in.

speaker-0 (43:02.136)
Yeah, which always sounds a little weird to us as mammals. The idea back when we were thinking that T Rex and Nanoterannus were the same species, that as a juvenile, T Rex might have eaten totally different prey and acted differently and ran faster and done completely different sort of ecological niche filling than the adult would have done. And that’s probably still true. It just turns out the nanotyrannus is also there doing its own thing.

speaker-1 (43:26.862)
Yes. Another example is that juvenile Brachiosaurus wouldn’t be able to reach plants up as high as the adults. So it would have to go to different places to eat different plants and worry about carnivores that wouldn’t be going after the large adults.

speaker-0 (43:40.32)
Yeah. Whereas if it was a mammal, it would be like, Okay, climb on my back, baby Brachiosaurus, so you can reach the leaves or I’m gonna get them out of the top of the tree and feed to you down there or something.

speaker-1 (43:52.242)
that’s funny to think of a brachiosaurus climbing onto a back. All right, so this study started off by looking at dinosaurs’ closest living relatives, birds and crocodilians. Birds today need parents to take care of them until they’re nearly adults. Crocodiles take care of their hatchlings for several months to over a year and a half. And then as they grow up, they fend for themselves and their diet changes.

Alligators, for example, start off by eating insects, then they switch to crustaceans and fish, and then eventually on to mammals and turtles.

speaker-0 (44:25.592)
I should say most birds need their parents to take care of them until they’re almost adults because some of them are pretty precocial and take care of themselves. And they also get to adulthood or near adulthood really fast.

speaker-1 (44:37.587)
sometimes in a span of months. Yes.

speaker-0 (44:40.078)
Like a two or three months and they’re big enough to be like, Okay, I’m outta here.

speaker-1 (44:43.822)
Was it like chickens can start laying eggs after four months, and then I think pigeons are adults after six months? Mm-hmm. So it’s not the same level of commitment that mammals have. Yeah. Especially humans.

speaker-0 (44:54.594)
Yeah. Very true.

speaker-1 (44:56.782)
All right, well, what did dinosaurs do in the Mesozoic? It took them many years or even decades to reach their full size. And with dinosaurs, we see pods of young dinosaur skeletons preserved together with no adults nearby. So it seems that juveniles sometimes traveled in groups together, getting their own food and fending for themselves. It’s possible that in these juvenile bone beds, for whatever reason, some adults were there and they didn’t fossilize, but it’s hard to say.

For this study, they looked at mammalian faunas like Librea plus 18 more faunas, as well as dinosaurian faunas, including Hell Creek, Nemet, and sixteen more. I don’t want to list all the faunas. And they compared the body sizes of adults and juveniles. Young mammals are typically closer to adult size in terms of body mass than Mesozoic dinosaurs. You’d think how like a baby is small compared to an adult human, but not

that small compared to say a sauropod that laid an egg. Yeah.

speaker-0 (46:00.024)
Because yeah, a a human goes from say on the smaller end, five pounds up to two hundred pounds, which would be a factor of forty. Whereas with sauropods you could go from one pound up to I don’t even know how many tens of thousands of pounds, which is tens of thousands of times the size increase.

speaker-1 (46:20.962)
were the hatchlings even on their radar. I don’t know. Yeah. All right. So they examined three scenarios. One where only adults represented taxa, another that included adults and juveniles of all growth stages to represent taxa. And another where there’s juveniles living independently and then there’s adults without dependent offspring to represent the taxa. It’s a preliminary type study so that

simplifies things and Tom Holtz acknowledges that. But he suggests that because dinosaurs were on their own as kids, that doubled the number of species in their communities compared to mammals.

speaker-0 (46:59.349)
yeah, effectively doubled, I guess. Yeah.

speaker-1 (47:01.366)
Yeah. Because they’re doing all different stuff and eating different things and yeah, just living different lives.

speaker-0 (47:07.724)
It could be even more. You could imagine it being three different cause sometimes like you were talking with alligators, right? Some of stay in like trees and things, these smaller lizards. And then as they get a little bit bigger, they might be eating smaller prey. And then when they’re larger, at the largest they could be behaving differently.

speaker-1 (47:25.868)
It’s also possible that dinosaurs had a lower metabolism compared to comparable size mammals, which would allow for more diversity in the same area because they just wouldn’t need to eat as much. So the takeaway here is that dinosaurs change what they ate over the course of their lives. And adults and juveniles can be considered different functional species because they occupy different niches, what they eat, what species can threaten them, where they can move. So just like what you were saying, Garrett.

speaker-0 (47:51.884)
Yep. So even if Nanotyranus and T Rex are different genera, doesn’t mean that juvenile T Rex didn’t behave totally different and still look a fair amount like Nanotyrannus in a lot of ways.

speaker-1 (48:03.298)
Yeah. They might have been rivals. Mm-hmm. Food.

speaker-0 (48:06.36)
Well, yeah. And also probably rivals with others of the same species based on all the face biting that T Rex seemed to do.

speaker-1 (48:14.09)
It’s a tough life. That wraps up this episode of Inodino. Thank you for listening. Stay tuned. Our next episode of Inodino, we’re going to have at least one new dinosaur and we’ll be talking about dinosaur growth. And don’t forget, you’ve got about one week or so left to pledge if you haven’t pledged yet for the dinosaur rookie cards. You can do that at inodino.com slash cards. Thanks again, and until next time.

(Approximate times)

• 00:00 Introduction to Tara Tassone and her work
• 01:00 Designing the new dinosaur trading cards
• 03:05 Details about the spiky hadrosaur How Long Dong I
• 11:47 Interview with Tara about her design process
• 21:56 The story behind the Atacama Titan discovery
• 30:07 Tara’s work at the Mariners Museum
• 34:04 Her own paleo art studio Feather and Fang
• 40:04 Favorite animals and design challenges
• 44:47 Insights into dinosaur evolution and origins
• 46:53 Closing remarks and upcoming episodes

Summary

Join us as we explore the paleontology and design with Tara Tassone, a talented graphic designer and illustrator. Discover her creative process, her work on dinosaur cards, logos, and her role at the Mariners Museum, along with insights into recent dinosaur discoveries and the history of maritime engineering.

Takeaways

• Tara Tassone’s background in paleo art and graphic design
• The process of designing dinosaur logos and trading cards
• Details about the new spiky hadrosaur How Long Dong I
• The discovery and significance of Atacama Titan in Chile
• Insights into dinosaur evolution and early origins
• The role of design in scientific communication
• Tara’s work at the Mariners Museum and her own studio
• The challenges of illustrating dinosaurs accurately

Keywords

paleontology, dinosaur art, graphic design, dinosaur cards, paleontologist, museum, Atacama Titan, dinosaur evolution, paleo art, dinosaur design

Hello and welcome to I know Dino. Keep up with the latest dinosaur discoveries in science with us. I’m Gary And I’m Sabrina. And today in our five hundred and sixty-ninth episode

speaker-1 (00:57.4)
We’re talking about a new spiky hadrosaur. I know, but maybe that’s fitting because it kind of goes along with our spiky dinosaur rookie trading card that we have already announced. And if you’re interested in getting a dinosaur rookie trading card, because what better way to celebrate dinosaurs that were recently named than with a card? You can do that at inodino.com/slash cards.

speaker-0 (01:00.494)
Likey Hadrasaur.

speaker-0 (01:09.112)
Hmm that we’ve already announced.

speaker-1 (01:26.41)
Later in this episode we have an interview with Tara who designed all of the dinosaurs and the cards and did an amazing job. Thank you, Tara.

speaker-0 (01:34.764)
should mention it’s not just cards. She also designed some stickers for us, which are available as a sticker, a magnet, and a keychain. So if you’re into one of those things instead, we also have a pin. So yeah, lots of stuff to look at on inodino.com slash cards.

speaker-1 (01:51.734)
Now is the time to pledge. We’re about a week in ish to the campaign. Mm-hmm. And then after our interview, we’ll talk about Dinosaur of the Day Atacama Titan, which is one of the most complete titanosaurs found in Chile.

speaker-0 (01:55.842)
Yeah, it ends at the end of July.

speaker-0 (02:05.784)
Probably in the Atacama Desert, I’m guessing.

speaker-1 (02:07.798)
Yes. And our fun fact is that dinosaurs may have originated 10 million years earlier than we previously thought.

speaker-2 (02:08.814)
Yeah.

speaker-0 (02:15.938)
Da da da. But before we get into all that, as always, we’d like to thank some of our patrons, because without them, there would be no I know dino. So thank you all. This week we’d like to thank Trev, Kiani, Verociraptor, Benetseratops, another updated name, Pota, Morgan E. Clove, Bobby, Tyrannosaurus, Brooke, and Norwegian Saurus.

speaker-1 (02:41.966)
Thank you so much. Yes, like you said, Garrett, without our Dinoidals, we would definitely not be here. We wouldn’t be able to do this show. We wouldn’t be able to do things like trading cards. So we hope you enjoy all of the perks. Because one of the perks, if you’re a paid patron right now, is if you pledge for the dinosaur trading cards, you get an extra special Nano Tyrannus card. It is.

speaker-0 (03:05.614)
Yeah, it’s a good one.

speaker-1 (03:08.248)
So you can learn more and sign up at inodino.com/slash cards. And again, thank you to our Dinoidalls. Jumping into the news, we’ve got a new spiny hadrosaur. This is how long dong I’m published in Nature, Ecology, and Evolution by Jin Dong Huang and others. Yeah. They found this nearly complete articulated skeleton of a juvenile. The lack of fusion makes it seem like it’s a juvenile. It’s about eight feet or

Almost two and a half meters long. It’s got some detailed fossilized skin with spines that are not seen in other dinosaurs. So we know about hadrosaur scales. We ha there’s a lot of hadrosar quote unquote mummies. They’re mummies because sometimes it’s more like a clay mold over some of them we’ve talked about and

speaker-0 (03:56.044)
Yeah. It’s I would say there’s a lot of them compared to other dinosaurs, and maybe an absolute count, but I think you might be able to still count on both hands. There’s not a ton of dinosaur mummies or hadrosaur mummies.

speaker-1 (04:11.202)
We’re finding more and more and there’s some sites where paleontologists knew that mummies had been found and then they’ve been re-excavating and finding more. We’ve talked about this, yes. But anyway, we didn’t know about the spikes on Hadrosaurs.

speaker-0 (04:25.23)
So these aren’t spikes like on Spike Omelus or on a stegosaur. They’re spikes like little spikes, more like a hedgehog in the skin.

speaker-1 (04:34.062)
Porcupine’s quills, yeah. cool. At least they’re more like those than protofeathers. And the spikes were cornified. That’s tissue that’s hardened into a horn. The skin is preserved at the cellular level, which is pretty amazing. So you can see the cellular structure of the skin. You can see the keratinocyte nuclei, which is a cell found in the skin. There’s two types of scales and spikes here.

Part of the hadrosaur’s tail has rows of large overlapping shield-like scales. Most of the scales are ovoid, they’re shaped like an egg. There’s also some small spikes and small tuberculate scales, so small rounded bumps. There’s patches of small rounded non-overlapping scales around the neck, chest, hip, and base of the tail. Most of those are rounded, some are egg-shaped, some are polygonal, and they have spikes in between them. Most of these spikes are tiny. They’re like two to three millimeters long and

point one millimeters wide at most. Thistle. Yeah, so definitely not like spicomellus. But they’re similar to protofeather filaments that we see in Calindodramaeus. Mm-hmm. There’s also some medium sized spikes in between the smaller ones. Those are up to five to seven millimeters long.

speaker-0 (05:34.936)
Yeah.

speaker-0 (05:40.472)
Okay, which is a little firmer.

speaker-0 (05:48.758)
So half an inch almost, maybe a quarter inch actually.

speaker-1 (05:52.618)
Still pretty small. Yeah. And then there’s some large spikes too around the chest, but they’re poorly preserved. The largest spike is a little over forty-four millimeters long and almost eight millimeters wide at the base.

speaker-0 (06:05.398)
Okay. That’s pretty. I mean, eight millimeters wide at the base. So that’s like a quarter inch in diameter and then it almost two inches long. So that’s more like a really nasty thorn that you’d find on like a vine somewhere. Mm-hmm. Yeah, that I could see how that would be a deterrent for getting bit. It would be really funny if because we’ve talked before about like how did hadrosaurs coexist with all these large meat-eating dinosaurs, because they weren’t as fast as like

Or nithamimosaurs and stuff. Yeah. If the answer was just like they were spiky, they were like a bunch of porcupines.

speaker-1 (06:40.686)
It seems like there’s multiple roles for these spikes because there’s so much variation. And it’s not clear if adults had them too, because again, this one’s a juvenile.

speaker-0 (06:49.9)
yeah, that’d be interesting. They’re little pincushions growing up to deter some of the smaller predators, but then when they get bigger they have to they can run faster so they don’t need them or something.

speaker-1 (06:59.97)
Yeah, and so maybe it’s possible the spikes helped it keep warm, but the spikes are scattered, so we don’t know if they’re dense enough to i actually provide any insulation.

speaker-0 (07:09.164)
Yeah. And then you it’s hard to say for sure if they were that scattered when it was alive or if it’s a preservation thing. Although it sounds like the preservation’s pretty good, so

speaker-1 (07:16.93)
Yeah, right on the skin. The scientists couldn’t observe melanosomes in the spikes, so it’s hard to tell if they were for display or camouflage. We don’t know colors. Color. It could be like with lizards and snakes that there’s bristle like spines on the scales that are microscopic and then they can help detect vibrations. Although the spikes on how long are much larger. So it seems most likely like what you were talking about, Garrett, to deter predators. The spikes just make it harder to swallow the dinosaur.

speaker-0 (07:25.964)
Yeah, it’d be nice to know the couple.

speaker-0 (07:45.609)
If you’re covered in thorns, yeah.

speaker-1 (07:47.598)
It doesn’t necessarily mean how long was protected from teeth and claws, but it would have been harder and more time consuming to kill it and eat it.

speaker-0 (07:54.636)
Yeah. You don’t have to be impossible to eat, just harder than the other options.

speaker-1 (07:59.906)
Yes. Now the spikes are similar in some ways to protofeathers. They’re cylindrical in shape. They have a hollow structure, cornified skin. The more recent hypotheses suggests that the first stage of feather evolution wasn’t a hollow structure though. Instead it was a simple filament stuffed with melanosomes, and it formed this dense protoplumage. So the hollow spikes on how long are likely not an early stage in feather evolution. They’re not long scales either. We see scaly spines in modern squaw mates and

Calindodramaeus, too, but they come from a larger base. So it seems that these spikes have a distinct evolutionary origin. And how long is a basal hadrosaur? For comparison, Cytacosaurus has long bristle like structures on its tail that’s also cylindrical and seems to be like tubular skin structures. So those bristles for Cetakosaurus probably aren’t directly related to feather evolution either. Yeah. The paleoart of how long is

speaker-0 (08:53.186)
Yeah, interesting.

speaker-1 (08:57.186)
Shows it walking on all fours, although it looks like it could walk on two legs if needed, and it’s got a bulky body, a beak, and a long head. So what you would expect for a hadrosaur. Mm-hmm. It lived in the early Cretaceous and what is now Liaoning China, found in the Ixian Formation. And there were a lot of small predators in that formation, as well as U tyrannus. So having the spiky deterrent was probably beneficial. Yeah. The type species again is How Long Dong I. That genus name means spiny dragon, and it refers to its in

Tegumentary structures, the scales with the hollow spines. And the species name is in honor of Dong Ji Ming, quote, pioneer of dinosaur research in China and one of the most influential paleontologists of the past sixty years who recently passed away. So there we go, that’s our latest spiky dinosaur, and it’s not an ankylosaur.

speaker-0 (09:42.754)
That was so cool. Yeah, totally different type of spikes.

speaker-1 (09:45.922)
Yeah, maybe this will make Hadrosaurs more popular.

speaker-0 (09:48.576)
Yeah. Imagine if they all were like this. I’m really interested to hear what people think about if it was just juveniles, just adults, if it was just this species, or if there’s like a group it was narrowed down to. What I was thinking is if we end up doing cards for twenty twenty six, if the cards for twenty twenty five are popular, this would be a really cool one.

speaker-1 (10:08.142)
Ooh. And there you go. Pledge for the cards of twenty twenty five so we can do this again next year. That’s InoDino.com slash cards.

speaker-0 (10:14.82)
And do this one.

speaker-2 (10:16.312)
Yeah.

Ha ha.

speaker-0 (10:21.376)
And speaking of advertisements, we’re gonna pause for a quick sponsor break and then we’re gonna get on to our interview with Tara.

speaker-0 (12:31.222)
And now on to our interview with Tara, who helped design not only our cards for this year, but also our logo, our I know paleo logo, lots of things. So, of course, we talked quite a while with Tara. We had a lot to talk about. So we have an extended version of this interview. And if you’d like to check that out, check out your premium content feed on Patreon or Apple. And there’ll be a timestamp in there to get to the

speaker-1 (12:41.07)
Thank you, Tara. Yes.

speaker-0 (12:57.216)
End of the interview in the ad free version of the show. If you want to skip over this shorter version. But without further ado, here is the interview. We are joined this week by Tara Tassone, who is a graphic designer and illustrator, and she’s a graphic designer for the Mariners Museum and Park in Virginia. But we’re mostly talking to her today because she designed our new dinosaur rookie cards, as well as in the past, our I know Dino logo and our I know paleo logo.

So thank you so much for joining us.

speaker-2 (13:27.582)
Thank you guys for having me.

speaker-0 (13:29.166)
So I guess maybe we should start a little bit before that work and say, How long have you been doing paleo art?

speaker-2 (13:39.022)
So I want to preface I am not a trained paleo artist. I have no background in biology or paleontology, but I’ve always had an interest in dinosaurs. And so ever since I was a kid, I was drawing dinosaurs. And probably in the past like couple of years or so, maybe like five or six, I started really like honing in on like learning the anatomy, learning the musculature, all the stuff that goes into paleo art.

speaker-0 (14:04.846)
Nice. Yeah. I remember in our Discord server years ago now, you posted some cards that you designed for a game, and they look so cool. You did a better job of sort of capturing most of the dinosaur in a small awkward vertical space and keeping it, you know, anatomically accurate than I think I’ve seen elsewhere. So that was part of the reason we were thinking of you when we were looking at.

making some cards of our own, ’cause it’s not easy to fit a very long horizontal animal into a vertical space.

speaker-2 (14:42.12)
And that was so that was a school project. It was my senior capstone thing. And that I ran into that challenge immediately was how do I get this very long, compared to any other animal, awkwardly shaped animal into a little tiny rectangle. And a lot of it was the tail. Was trying to figure that out. So I figured, well, if I just turn them a little bit, that might help and have them facing forward. But yeah, the premise for that game.

my thought process was there’s always dinosaur games and there’s always horror games. You don’t really see dinosaur tabletop horror games that are accurate. Sucker, why not give it a shot?

speaker-0 (15:20.238)
Nice. I remember too another thing you posted in in our Discord where you did like a logo concept for I think it was La Brea Tar Pits or something. that I think looks cooler than their actual logo. But we should just like forward it to them and be like, you should hire this designer to make this for you.

speaker-2 (15:41.038)
That one we had a list of museums to pick from for a class project. I was like, Look, right, I want right. And they worked.

speaker-0 (15:47.904)
Nice. Very cool. And then obviously a little bit later you designed our logo. Mm-hmm. How did you when you’re designing a logo? Because I feel like you’ve done a couple at this point, where do you start? Like how do you decide what you’re gonna do?

speaker-2 (16:05.342)
so with any logo, my first step is research and development. So I’ll take a look at what other similar either company or in your case a podcast. I’ll just kind of look and see like what are other people doing and then what could be different, what is everybody doing well. So in your case, I looked at a lot of Scicom stuff. I looked at a lot of like just nonfiction type of podcasts.

And then from there, I also looked at because I knew you wanted to keep the T Rex. Then I started gathering a bunch of images of T Rex, just kind of seeing like, well, here’s all these stylized images, here’s the more realistic one, just kind of gathering everything that I might be drawing inspiration from.

speaker-0 (16:49.826)
Nice. And I think you did an amazing job, obviously. And part of that to me with like a good logo is I mean, logos are supposed to be sorta simple, kind of by definition. You know, they’re not supposed like our old logo was basically a picture that was turned into like a logo shape. But it’s so tricky with a dinosaur or like how we prefer a very scientifically accurate dinosaur, but also making it super simple because they’re kind of contradictory things.

But I think you did a great job of just like highlighting a couple of the details so you can tell like, yeah, this is this isn’t like a cartoony dinosaur. This is right the real deal.

speaker-1 (17:28.205)
Colors too. They really make it pop.

speaker-2 (17:31.246)
And it’s funny because any of the designer probably has like this huge process with their colors. I I’m sure in the back of my mind there was probably color theory going in there. But this one I was like, these look good. And then I just, it just happened to click. I’m like, perfect. All my designer friends, they’ll be listening to this, just going,

speaker-0 (17:45.654)
Nice.

speaker-0 (17:51.992)
How long does it take you when you’re working on a design? Because you were talking about you got to do your background research and all that kind of stuff. And then I know it’s mostly digital these days. So then you have to actually create the artwork. About how long does it usually take you to make something?

speaker-2 (18:08.222)
usually give or take maybe about a month. It really just depends on if there’s deadline. Like, well, everything has a deadline, but it really just depends on is there already a clear idea in mind or is are we just like starting like completely scratch. And I’d say maybe a couple of weeks to a month or so because it’s I kind of just I’d say the bulk of it is the ideation because without that if you go into it just kind of like half with an idea.

you’re gonna go back and start changing stuff. And that’s kind that’s what happened with the cards a lot, is I would think I would get an idea and then I’d be like, no, never mind. Yeah. I’d say like a logo and any subsequent branding take for for me at least give or take a month. But I can always adjust if need be. Yeah.

speaker-0 (18:54.494)
That’s sort of not working on it eight hours a day ’cause you have a real full time job in addition to

speaker-2 (19:01.351)
Correct. Yeah. Now if I had if that was my full time job was doing that, I could probably do it within a week.

speaker-1 (19:06.616)
Yeah. Gotcha. Well you’re also going through multiple rounds too, because I know you do like the sketches and then various rounds of Yes. And then eventually the finishing touches and everything.

speaker-0 (19:14.903)
Alteration.

speaker-2 (19:19.262)
Right. Yeah, mainly the sketches, because that’s like when you’re really coming up. So that’s where it goes from ideas to concepts is well, here’s an idea. How do I turn into something that looks tangible and like there’s you could see what the intent is. So I think that’s to me the hardest part. And I’m always thinking back to like all those thumbnail sketches we had to do in school. Your teachers like, all right, you gotta have like 20 sketches. And it’s like, how am I possibly gonna come up with 20 ideas? And it

does help is doing those exercises. I think I shared like I think about like 18 or 19 designs with you guys before we landed on this one.

speaker-0 (19:49.869)
Ace.

speaker-0 (19:55.214)
Yeah.

speaker-1 (19:56.64)
It was a lot. Yeah.

speaker-2 (19:57.312)
Think I had like a grid of sketch.

speaker-0 (20:00.156)
yeah, yeah. I remember yeah, like different sizes of how big the Ino Dino part is and like different poses for the dinosaur and all that stuff.

speaker-1 (20:07.656)
And that was for a concept where we knew we wanted T-Rex. And then we go to Ino Paleo and it’s like, what kind of animal should we deal with?

speaker-2 (20:15.832)
Yeah.

speaker-0 (20:16.28)
Yeah. Could be any animal.

speaker-2 (20:19.82)
And what made that actually easier was because now we have a a visual language going on with the Ino Dino logo. And I thought, all right, we know it’s gonna be silhouette, we know it’s gonna be blacked out. At that point, it was just a full creature, but then it turned to, all right, here’s a creature. What pose is it in? Because it’s like some of them, I forgot was a terror bird. It was it was one of the creatures where its jaw judge like and again, this is me not knowing the fine motor skills of

the animals and stuff or how they the musculature works. But I was like, I don’t think our jaw can open that weapon. So so for some things I had to get like a little bit creative, but it’s like, it’s a two D dinosaur. It’s okay.

speaker-0 (20:59.362)
Yeah, I remember the options for I know paleo, maybe because it was more recent than I know dinos logo a lot better because we had I remember I really liked all four of those. The there was like you said, the Terror Bird. There was also a Smilodon and a Quetzel Coatlas and a Dunkel Ostius. and also the Anomalocaris. Yeah. Yeah yeah, maybe there was another one.

speaker-1 (21:20.898)
I remember you send it and you’re like, I have my favorites, but you guys tell me.

speaker-0 (21:27.399)
But we liked all of them so much.

speaker-2 (21:30.474)
If I said it, I was like, I don’t want to skew them, but I was like, I really like the anomaly cars. Yeah. And the polls were leaning that way, you guys were leaning that way. And I’m just going here, yeah. I’ll go according to plan.

speaker-0 (21:41.976)
Yeah we couldn’t.

I forget which ones we narrowed it down to. I wanna say maybe it was Dunkelastius and Anomalocaris.

speaker-2 (21:49.858)
Think it was the dunk, yeah. And that one it was a close second favorite of mine too. And I was like, that that’s pretty good.

speaker-0 (21:56.632)
And then you snuck in like some detail. I wanna say that you said it was from the Burgess Shale, the sort of like background.

speaker-2 (22:04.526)
So because for the background on the T-Rex logo, that is actually taken from a skin impression of a tyrannosaur. And for this one, I thought, well, we can’t use that because it’s like, you know, it’s not a dinosaur. but also that’s the whole point of that set that podcast is it’s not dinosaur, it’s nothing else. I thought, well, what will work with the animalcaris? And I thought, Virgil shell. So like all all of those are and I don’t remember what all the species are in that, but I figured, you know, taking

little fossils with little shells and stuff and it seemed like, well, these are recognizable the fossil. If you know that one, then hopefully I didn’t write. But

speaker-0 (22:39.47)
Yeah, it’s really cool. It’s really subtle too. It makes it makes the art pop a lot more because it’s not just like a simple plain background and you can easily not even notice it’s there and just notice there’s like a little bit of texture to the image. But when you blow it up to like full size, you can actually pick out the different fossils if you’re looking for them. That’s cool. I didn’t remember that about the skin of the T Rex on our I know Dino logo. That’s cool.

speaker-2 (23:05.464)
Yeah, there was some creative liberties taken just to make the actual pattern mesh together. But yeah, a lot of them are kind of I took the image and was kind of like, Yeah, that’s that’s a relative shape of it.

speaker-0 (23:14.424)
Nice. So cool.

speaker-1 (23:16.034)
Yeah. So for the cards, I know we started off with Nanotyrannis and Spicomellus for sure.

speaker-0 (23:23.628)
Yeah, because they were the two finalists from our top twenty-five or sixteen. We started with sixteen dinosaurs for twenty twenty-five, and then we had people like narrow down which one was the best. Those two were the final contenders. But then yeah, narrowing it down farther than that was tricky. And I think we mostly leaned on you to decide which ones to draw.

speaker-1 (23:35.237)
yeah, for the dino duels.

speaker-2 (23:49.494)
So that came down to I was gathering paleo art and fossil material from like all of these things and a lot of it came down to what can I find reference?

speaker-0 (23:59.702)
Mm-hmm. Yeah, that’s good. And it’s good in a lot of ways. For one, it makes the art more accurate because you’re basing it on a skeleton rather than like a single vertebra. But also, a lot of these animals that you picked are really interesting because they’re not when we were doing because we pre-recorded these little videos about each card, and we got to like the fourth one and we’re like, this is another herbivore.

We’re like we’re very herbivore heavy. And in dinosaur diversity, a lot of the carnivores kind of look the same, especially when you’re sort of simplifying them down to like the card size and you can’t necessarily see all the details on their body. You know, a lot of these theropods just kind of look a lot alike. But the herbivores, especially you’re talking about like spicomellus and stuff, have some radical differences.

So it was really cool to see how you highlighted the differences of these different herbivores in the art.

speaker-2 (24:58.668)
Yeah, that I was it a lot of it came out of posing as well because I did run into the issue where I wanted to pick is it Mexitrachin? Is that how you say it? I almost picked that one, but then it’s like, well, I already have a feathered theropod and they both kind of fill in the set that same herbivorous feathered thing with long arms. So I was like, let me not do that one. So I picked and chose. But then I know with both NATO Tyrannus and Tameri Raptor, I like, well, right, both.

big pheropods, how do I differentiate these? I figured just change the pose. ‘Cause I know I kept thinking in one of the Jurassic World movies, a lot of the producers on that were worried that people were gonna think it’s all the same dinosaur and there should be some people who think that, but you know, hopefully I made them different enough.

speaker-1 (25:45.613)
Yeah.

speaker-0 (25:46.626)
Yeah, that reminds me, I feel like they did that with a little bit with like Spinosaurus and T Rex. They changed the way that it was posed a little bit for their logos, but actually not that much. They should have changed.

speaker-2 (26:00.29)
No, the reason they added the spikes on the Giganotosaurus is in the movie is because they didn’t want people to confuse it for the T-Rex.

speaker-0 (26:09.825)
that’s funny.

speaker-1 (26:10.958)
That makes sense. Well, I think he did a good job differentiating.

speaker-0 (26:14.22)
Yes. Yeah. I think my favorite is Yuan Yanglong, the Love Bird Dragons, because there’s like sort of a behavior element to it and they’re like looking at each other so lovingly. I just I love that one.

speaker-1 (26:27.982)
much at the Duonigas is I I like all of them. But just something about the way it’s looking up and then the big claws.

speaker-0 (26:30.894)
Cool too, yeah.

speaker-0 (26:35.798)
Yeah. I just realized I didn’t say spicomellis and that’s probably like blasphemy.

speaker-2 (26:42.498)
I like to take the dune, I guess there’s like a tree outside of the frame of the car that you can’t see if he’s looking at the home get that tree.

speaker-0 (26:50.498)
Yeah, and you also picked different animals as your references for each of them, right? To sort of like decide what kind of coloration to use and things like that early in the process.

speaker-2 (27:02.914)
Yeah. So when I’m coloring my dinosaurs and it’s not like a hardened rule that I do for all my paleo art, but what I like to do, I like to look at the animals that are currently in the location that where these fossils were found in. So for example, for the Dunicus, I’m blanking on where this thing was found, but one of the animals that lives there now is a black belled caper caley. And I thought that would be a great reference because they’ve got it’s not just black plumage, it’s this nice

Almost like a blackbird where it’s a little bit shiny, a little bit shimmery, got some glue tints to it. And then my favorite was for the Yuanyang Long. When I looked into the etymology of it, it comes from the term for mandarin ducks, which they made for life. And I thought this would be a perfect depiction for these dinosaurs. It’s like, well, you have a male, you have a female. It works. Especially the the male mandarin duck has this beautiful coloring. I thought, you that’ll work perfect.

for dinosaur, ’cause a lot of male birds have that very vibrant plumage in the females maybe not so much, but it’s like that’d be a really cool dichotomy to feature.

speaker-0 (28:08.598)
Yeah, that is so perfect. And yeah, I remember I we kept saying Yuan Yanglong, it means lovebird dinosaur or lovebird dragon in Chinese. And then I was rereading the paper and it mentioned the Mandarin duck. And I was like, wait a second, we keep saying it’s lovebirds. But then I looked into it a little bit more and it was like, okay, in Chinese, the or I should say in China, the Mandarin ducks are

They’re equivalent of a lovebird, which is why they put it that way, because it’s like they’re fame they’re the birds that are famous for mating for life in China, or at least in parts of China. So that’s why they named it that, even though it doesn’t literally translate to lovebirds, because they don’t have the same lovebirds in China that we have elsewhere. Just in case anybody hears this and is like, that’s not that doesn’t mean lovebird. Yeah, they all turned out so great. And then we also very much appreciate because

Originally we were like, we want you to do the art and we’ll figure out what to write on it and how to structure that. And you were like, Well, I can help you figure out how to structure the writing on it. And then you actually suggested some of the writing too, which was awesome. So thank you for all of that.

speaker-2 (29:19.79)
Yeah. a lot of that also comes from working with some people on my team do marketing and I’ve been slowly getting exposed to new writing styles ’cause I’m not a writer. I’m just I make the visuals, but it’s like it’s good to pick up some stuff here and there.

speaker-1 (29:32.352)
Mm-hmm. Yeah. And do you want to talk about being part of that team and and where you’re working right now?

speaker-2 (29:39.352)
Sure. So I am at the Mariners Museum and Park that’s in Newport News, Virginia. So if anybody’s ever on the East Coast and wants to visit it, same as plug at the dollar for admission. So our that’s our goal is to make it as accessible as possible to all communities. And we do a lot of well, it’s mariners. So it’s a lot of nautical stuff, it’s boats, it’s anything that was on ship. So we have like military, we’ve got recreational, we’ve got historical, we’ve got pretty much everything. One of our biggest things is we have

a lot of stuff related to the USS monitor, pretty much a lot of civil war stuff. So yeah, it’s not it’s a little bit different than paleontology of its stuff. It’s it’s stu it’s still a museum and I’m I’m loving it. So then I do the graphic design work there for multitude of different teams.

speaker-0 (30:22.318)
Was the monitor ’cause it was the monitor of the Merrimack where there were like the steel boats and the Civil War? Is it Civil?

speaker-2 (30:27.874)
Ironclads, yeah. So we’ll yeah. So yeah, monitor was Union, the Merrimack, or well, to in the battle, it was actually the CSS Virginia. that’s right. Yeah, so it was it was a weird little thing that happened there with the naming of that, which they’re listening, they’re gonna just got told the story the other day, and I forget. It did change names over time. And not really over time, it was just one event that changed it. But yeah, but Battle of Hampton Roads. So it’s really cool that we get to see.

parts of history just on a daily basis, just working there.

speaker-0 (31:02.318)
Did the monitor win? Did either of win? I feel like it was a draw, but I

speaker-2 (31:06.816)
It was a draw. So I think the monitor took out more Confederate ships, but the Confederate army, they successfully held the like they held up their not really a sea I don’t know if it was a siege, but they nobody got past them. So it’s both sides are claiming victory, but in reality

speaker-0 (31:25.304)
They were the same as when they started out, basically.

speaker-2 (31:28.184)
pretty much and then not long after both ships sank, one got hit by a rogue wave. That’s the monitor that’s now off the coast of North Carolina. The other it got stuck. So they’ve had to they had to scuttle button and take all the parts off of

speaker-0 (31:41.71)
So you just have the what did you say, the turret from it? So they w somebody went down and collected that piece and brought it to the museum?

speaker-2 (31:47.958)
Yeah, so that’s the rotating part of the top that all the guns are shoot being shot out of. But they found monitor in and again, if they’re listening to me, I’m so sorry. They found it in the 70s where it was offshore. And then in 2002 or three, they were able to dive down and retrieve parts of the ship. And they pretty much had because this turret is like 20 feet across, it had like seven tons of coal that had landed in it because of what it.

When it sank, it flipped upside down. So all the coal went to the turret. And then the rest that so is the rest of the ship. So they had to cut through part of the ship just to get the turret out. And so they got the turret, they’ve got the engine, they got some of the guns. Obviously, the rest of the ship is still down there and they really can’t bring it up, but it is actually turned into it is a national marine sanctuary. So if you want to learn more about that, Noah has some great information.

speaker-0 (32:42.68)
That’s so cool. Something about giant ships. I just like big things maybe, but I like dinosaurs and I also like big old ships.

speaker-1 (32:50.67)
And history.

speaker-0 (32:53.804)
It is all history too, that’s true. So what as a graphic designer for a maritime museum, what kind of stuff are you designing there?

speaker-2 (33:04.45)
So a lot of it is marketing material. So just promoting the museum or stuff throughout the museum as well, like a lot of brochures for to hand out to guests. I get to do some scavenger hunts for children, which is really fun. So we have our education team that works on that. And then I get to help either illustrate it or just find some graphics for it. A lot of signage just really promoting like what’s in the museum. Yeah, just really big variety of things.

speaker-0 (33:27.47)
That’s cool. Do you have is your favorite thing there, the monitor? Or is there something like niche that is your favorite?

speaker-2 (33:35.256)
So we’ve got one of the things there is we’ve got this giant catamaran that took part in the America’s Cup back in 2013, I believe. And for those that don’t know this cat catamarans are ships and they’ve got like these big things that stick out the side of them that help it stay in the water. But then it’s got these big blades that sit in the water and it’s it’s gotta be at least sixty feet tall. It’s giant, not even really a sail, but just this big fiberglass pillar.

Then when these things start moving, they’re going like 50 miles an hour in the water. I’m not sure what it is in knots, but what gets so fast that the blades are just barely in the water. So it’s essentially flying. And so we have this in the museum. And it’s not even fully out there because the the tall part is so big, but this thing is just so cool. And I thought it was like, yeah, that’s my favorite.

speaker-0 (34:28.558)
The it that’s funny to see the or hear the juxtaposition of this old like civil war steel boat and then this modern fiberglass hydrofoil catamaran situation. That’s super cool.

speaker-1 (34:43.522)
Yeah. But I know you do other paleo art in addition to our cards and everything because you’ve got your own shop, right?

speaker-2 (34:51.17)
Yeah, so I run Feather and Fang Studio. That’s my Etsy shop. So it’s funny, I do like the really serious, realistic paleo art, but then I also do this really cutesy style too. A little more kid friendly, we’ll call it. But yes, like I do keychains, I do stickers, I do prints. Yeah, a lot of little I do I sew sometimes, but that’s not I don’t really have much of that in my shop right now. But

speaker-0 (35:13.624)
That’s hard to make in bulk for sure.

speaker-1 (35:18.572)
What’s your favorite animal that you’ve illustrated or or created something for so far?

speaker-2 (35:24.194)
gosh, that’s a tough one. I’d say a recent favorite is I did the set of, I called them dangling dinos. It’s this little keychain that likes it’s got moving parts on it, so the whole thing can dangle, it’s a little tail that hangs down. And I did a triceratops. And it was the last, I did a bunch of other sketches for stuff. And this was the last one I did. And I thought, all right, one more just around the set. And I think it’s one of the cutest things I’ve done.

speaker-0 (35:53.326)
So which other ones are there other than triceratops in your dangling dinos?

speaker-2 (35:58.466)
Yeah, so I did my first wave of them. I did what did I do? I did Denachirus, I did Dilophosaurus, and then it was kind of just a generic raptor, which I f like in when I was drawing it, I didn’t really have much of a species in mind. But the coloration kind of came out like the prehistoric plan of Velociraptor. So it’s Velociraptor with a kind of bulkier jaw. Nice. And then I did the herbivore set, which is Triceratops and Kylosaurus and Stegosaurus. And then after that I did the I the big three. So I did

T Rex, Spinosaurus, and Giganotosaurus. Nice.

speaker-1 (36:31.352)
Nice.

speaker-0 (36:31.874)
I like referring to those as the big three.

speaker-1 (36:34.062)
I was just thinking that that’s a good way to refer to them.

speaker-2 (36:36.692)
And it’s funny because we were just talking about differentiating the dinosaurs and like, you I drew I drew the T Rex, I drew the Spinosaurus, which that one was hard doing at that angle because like it’s got this big fin and you can’t like if you look at it straight on, it just looks like a line. So I kinda had to like hilt a little with the Giganotosaurus. I’m like, what can I do to this thing to make it look different than the T-Rex? So that I made sure like the proportions were way different, it’s a little bit skinnier, the skull’s a little bit narrower.

made the color different and I almost did and I forgot to actually add them on the final file. I almost gave it the spikes. Like from Dominion.

speaker-1 (37:13.195)
Yeah.

speaker-0 (37:13.646)
But people would recognize it that way.

speaker-2 (37:15.999)
They would. No, but I I made sure to give it the Giga Chin, the wage.

speaker-0 (37:21.922)
Forgot to ask earlier when we were talking about the cards what the hardest one was to design out of all the six.

speaker-2 (37:30.52)
So it’s between Zavacephaly and Nano Tyrannus. So the Zava, that one, because the pose I was going for, it was a very like it it was stepping like across the name of it and just trying to get that angle down. And then realized, well, it’s kind of everything else gets kind of cropped. This thing, it’s the whole body is within this thing. So it’s the odd one out. So I think that as well as trying to get that head angle right, because

trying to make it look like it’s got a domed head and not just a little bald man. Yeah. Yeah. So really just trying to get er all these little tiny minor changes. I think at one point I realized I’m like, what’s wrong with its hands? And I realized I drew the hands backwards. Like they the fingers were the opposite way of what they should have been. so I that was an easy change, but it was like that that almost fixed the entire drawing was the hands. I realized that one almost hit the end.

speaker-0 (38:28.195)
the hands are so tiny that it would be hard to notice for anybody else though.

speaker-2 (38:32.876)
It was one of those things like nobody also noticed, but I noticed. But then, yeah, so then the other one was the nano Tyrannus. That one was also very hard. And that’s actually why I’m in the process of like redoing that one. Just because I I had like so many different poses and I ran into the same issue of how do I get this really long animal into this little tiny rectangle? And one of the things I wanted to keep consistent across all the cards is having some element of it.

pop out of the card. And I know the Tameri Raptor, I already kind of had, depending on which angle I faced it at, it was either gonna be the back of the head or the tip of the snout poking out. But then I was like, well, if I do that, it’s gonna look way too similar to the nano Tyranna. So it’s there was so many things that just were like factors to consider. So that one I thought I had an idea and then I did it and then it’s like wow, kind of hate it. And that that’s just kind of how art works is you

And that’s honestly just part of my process is I need to see it completed before I realize it’s not working. And you know what how to fix it after.

speaker-1 (39:40.59)
I get that. That’s kind of like with writing. Sometimes you just need to put it down and then look at it later with fresh eyes.

speaker-0 (39:41.506)
Mesh.

speaker-2 (39:48.75)
Yeah, you gotta make it exist first, then you can fix it later.

speaker-1 (39:55.054)
Well, I personally love how all of them turned out. Yes. Yeah. I’ve been very excited sharing it with everybody.

speaker-0 (40:03.95)
Yeah. And we’ve had nothing but positive feedback too, which is awesome.

speaker-2 (40:07.854)
Glad people were enjoying them.

speaker-0 (40:09.678)
Cool. So if people want to check out your work and also your store, you mentioned your Etsy shop already. Could you remind me the name of that one?

speaker-2 (40:21.804)
That is Feather and Fang Studio. The mascot for that is a little dinonicus that I drew named Tawny. She has little owl ears. And then so for my design work, I have an online portfolio called TNTesign.com. And then for more of my illustration work, that is TNT Design with periods in between TNT. That is Instagram, yeah.

speaker-0 (40:45.056)
On Instagram. At T N T design, I guess.

speaker-1 (40:50.486)
We’ll make sure to put the links in our show notes too, so it’s easy to find. Yep.

speaker-0 (40:55.832)
Cool. Well, thank you so much for joining us. And also thank you for all your work designing these cards and our logos and some other marketing stuff related to the logos.

speaker-2 (41:08.462)
Of course. I’ve had so much fun creating this and you guys are amazing to work for.

speaker-1 (41:12.046)
Thank you. Thank you.

speaker-0 (41:14.392)
Thanks again, Tara, for the fantastic interview and for all your artwork. We really appreciate all the hard work you put into them.

speaker-1 (41:21.89)
Yeah, and it’s so fun hearing about your process.

speaker-0 (41:25.686)
And in just a moment we’ll get into our dinosaur of the day, Atacama Titan. It’s a fun one to say quickly. But first we’re gonna pause for a quick sponsor break.

speaker-1 (41:37.038)
And now onto our dinosaur of the day, Atachamatitan, which was a request from Ryan the biochemist via our Patreon slash Discord. So thank you. It was a titanosaur, it lived in the Lake Cretaceous and what is now Chile, found in the Tolar Formation. As a titanosaur, it would have walked on all fours, had a long upright neck, a small head, and long tail. It’s estimated to weigh between eight and sixteen tons. Oof. The type and only species is Atacamatitan chiliensis.

And that genus name means Atacama Desert Titan. Nice. It refers to the Atacama Desert where the fossils were found. And then the species name refers to Chile. Those fossils were found in 2001 by Chilean and Brazilian researchers, and they found fossils from one individual. It was found near Conquiv Viejo Town in the Atacama Desert.

speaker-0 (42:23.618)
No there were towns in the Atacama Desert.

speaker-1 (42:25.762)
Yes. I learned a few things about that desert. Well, first, only Atacama Titan and indeterminate dinosaur fossils have been found there so far. But the Atacama Desert is the driest nonpolar desert in the world and is the largest fog desert. Fog gives most of the moisture that the plants and animals need to survive.

speaker-0 (42:47.128)
Not much if it’s the dry

speaker-1 (42:48.558)
No, but it this happens because of hot humid air interacting with the two mountain chains around it, the Andes and the Chilean coast range. The average rainfall each year in the Atacama Desert is about 15 millimeters. my goodness. Yes. But it’s a great place to see the stars because there’s almost no light pollution. Mm-hmm. So there’s a few major observatories there.

speaker-0 (43:06.584)
Awful.

speaker-1 (43:15.276)
The soil of the desert has been compared to Mars, and that’s where some Mars scenes have been shot for some films. But anyway, back to Autocoma Titan. The femur was first found, it was eroding on the surface. So the holotype is a right femur, that thigh bone, part of an upper arm bone, or humerus, two backbones, dorsal vertebrae, some tail bones, caudal vertebrae, parts of the ribs and chest and other incomplete bones. And it’s one of the most complete titanosaurs found in Chile.

speaker-0 (43:42.658)
Me on. So it doesn’t have a lot of competition, it sounds like that’s not an amazing finding.

speaker-1 (43:48.586)
still. So it was named by Alexander Keller and others in 2011. Most of the fossils are a little distorted. They’re reddish and they’re heavy because there’s a lot of per mineralization. So mineral rich water seeps into the bones, water evaporates, and then the minerals form an internal cast.

speaker-0 (44:04.622)
So they’re basically filled up with rock. We don’t have the big air spaces that you often get in these sauropod vertebrae and other bones.

speaker-1 (44:13.432)
They’re heavy. But there’s unique features in the bones, like having rounded pleuroceels, as are hollow depressions to make the bone lighter, ’cause in life it needed its bones to be lighter. Mm-hmm. And it had a grassile thigh bone. Its arms or its forelimbs were stronger than its legs too.

speaker-0 (44:30.732)
almost sounds like a brachiosaur type situation. Yeah. Which I guess they’re on the same

speaker-1 (44:36.226)
Titanosaurs and brachiosaurs have a similar posture.

speaker-0 (44:39.584)
Yeah. They’re like closer cousins than they are to some of the other sauropods, at least.

speaker-1 (44:45.294)
And our fun fact is that dinosaurs may have originated 10 million years earlier than we previously thought. This was published in Proceedings B, it’s open access, by Chase Duran Brownstein and Christopher Thomas Griffin. So, dinosaurs may have been around about 250 to 240 million years ago. That’s 10 million years before the first fossils have been found. That the first fossils that we know of that are definitively dinosaurs are from about 230 million years ago.

Ago. Okay. But we’ve talked about this before because of track. Yeah.

speaker-0 (45:18.298)
yeah. And also psilosaurs. But I guess they’re talking about not just psilosaurs. Silosaurs being dinosaurs would push it back that far.

speaker-1 (45:28.108)
Yeah. So they modeled how dinosaurs evolved over time and found that dinosaurs had a burst of evolution early on and then diversified soon after they got started, which might be why it’s hard to understand the relationships between theropods, ornithiscans, and sauropods. They all just diverged so quickly, they didn’t even form key skeletal features that would show us their relationship with each other. And then once the three groups evolved, they settled in for a while. There was a drop in morphological evolution where they didn’t change as rapidly.

So they looked at the evolution of the earliest dinosaurs and they statistically analyzed nine morphological data sets that includes data on the shapes and sizes of dinosaur bones, certain features like horns, feathers, and other traits that dinosaurs had. And then they analyzed data related to the traits of the three major dinosaur groups. They looked at the estimated ages of fossils and previous evolutionary models to estimate when dinosaurs appeared and how fast they evolved. And it could be that this burst.

of evolution early on was from an extinction event. So there was more opportunities for them to adapt. There’s the Carnian pluvial event, that two million year long period of time where it rained. Mm-hmm. That was about 233 million years ago. That would have actually helped the dinosaurs because it shrunk the desert belt in the middle of Pangaea so dinosaurs and other animals could migrate across the supercontinent. Uh-huh.

speaker-0 (46:50.734)
Cooled things down a little bit. Yeah. Wettened them up.

speaker-1 (46:53.224)
Yeah. Helped with the plants, probably. So yeah. And this all tracks with the tracks that have been found, the ones that were in Poland, which is considered to be likely from close relatives of dinosaurs. Cause it’s really hard to tell from tracks what animal made those tracks. Could be.

speaker-0 (47:10.638)
Could be a real dinosaur. It’s kind of semantics at that point. Hmm. Very cool.

speaker-1 (47:16.386)
Yeah. Well that wraps up this episode of Inodino. Stay tuned. In our next episode of Inodino, we’ll be talking about a new sauropodomorph with a sturdy long tail. And we have an interview with Daniel Sepka, curator of science at the Bruce Museum in Connecticut, who’s also an expert on fossil birds. And don’t forget, now is a great time if you haven’t yet pledged for the dinosaur rookie cards. You can do that and choose from all kinds of perks at inodino.com/slash cards.

Thanks again and until next time.

(Approximate times)

• 00:00 Introduction to Theropods
• 03:06 Understanding Theropod Groups
• 06:01 Evolution of Theropods
• 08:58 New Discoveries in Theropods
• 11:57 Antiornithines and Their Characteristics
• 15:08 Gorgonavus and Its Significance
• 18:09 Large Theropods and Their Evolution
• 26:02 Exploring the Size and Characteristics of a New Tyrannosaur
• 29:02 The Evolutionary Significance of Tyrannosaurs
• 32:13 Unveiling the Validity of Nanotyranus
• 36:14 Adaptations for Carnivory in Theropods
• 49:19 The Evolution of Shorter Arms in Theropods
• 53:06 The Evolution of Theropod Limbs
• 56:37 Tyrannosaurus Rex: Scavenger or Predator?
• 01:00:04 Listener Questions and Theories on Apex Predators
• 01:06:03 Avimimus: The Bird Mimic Theropod
• 01:14:52 Tyrannosaurus Rex: The Tiptoeing Giant

Summary

In this episode, we explore the fascinating world of theropod dinosaurs, from their evolution and diversity to recent discoveries about their feeding behavior and social structures.

Takeaways

• Theropod groups and evolution
• Recent fossil discoveries and new species
• Feeding mechanics and skull stress analysis
• Social behavior and gregariousness in dinosaurs
• Size and speed estimates of Tyrannosaurus and relatives
• Arm reduction and predatory adaptations
• Feathered dinosaurs and their implications
• Fossil evidence of scavenging and predation
• New insights into dinosaur locomotion and gait
• The debate over Nanotyrannus validity

Keywords

theropods, dinosaurs, evolution, Tyrannosaurus, bird-like dinosaurs, fossil discoveries, feeding behavior, social behavior, paleontology

Hello and welcome to I know Dino. Keep up with the latest dinosaur discoveries and science with us. I’m Garrett. And I’m Sabrina. And today in our 568th episode

speaker-0 (01:02.808)
We have an episode about theropods, from the smallest ones, birds, to the largest tyrannosaurs, and a little bit in between. We’ll talk about the evolution of theropods, two new small theropods, specifically in antiornithene birds, an extra large tyrannosaur, more evidence that nanotyrannus is valid, how big the skulls and small arms of theropods affected how and what they ate, the fact that smaller theropods scavenged larger theropods.

And we answer a listener question about whether or not Tyrannosaurus was like a hyena. Hmm. It’s a theropodastic episode. Our dinosaur of the day is a theropod, Avimimus, that’s a small bird-like theropod dinosaur. And our fun fact is that Tyrannosaurus tiptoed instead of stomped.

speaker-1 (01:37.678)
That is a lot of theropods.

speaker-1 (01:49.77)
yeah, that’s a fun one. So don’t expect the Jurassic Park ground shaking water cup rippling stomps that you’re familiar with. But before we get into all of that, as always, we’d like to thank some of our patrons. And this week we have two new patrons to thank, and they are Kate and Alex. So thank you very much for joining. And then rounding out our shout-outs, we’ve got a patasaurus, tyrannosaurus, Verociraptor.

So we got three dinosaurs in a row with people’s names in them. I really like that. Also Obi Juan Kenobi, Spino Sam, Mary Siroliphus, Adelosaurus, and Grace.

speaker-0 (02:34.67)
Great names, everybody.

speaker-1 (02:35.956)
Yes. Lots of good dinosaur fied names in there too.

speaker-0 (02:39.096)
Yes, thank you so much for being Dino at all and supporting our show. If you’re considering supporting our show so we can make more content like this episode, but also a lot of bonus content. We do a lot of mini episodes and I know paleo episodes. You can head over to patreon.com slash InoDino and join. If you’re on the fence, we do have a member perk sampler so you can get a taste of what you would get with a paid membership.

speaker-1 (03:06.584)
Yeah, and next month you’ll be able to order something that only patrons can get.

speaker-0 (03:12.75)
Mm-hmm.

All right, before we get started into all of our theropod news, I thought it’d be helpful to break down some of the different theropod groups. And Gary, you did a great job with that. Ooh, it’s been a while now. Episode four hundred and ninety seven, how to tell a tyrannosauroid from a ceratosaur and a manorapterin. We had a listener question asking about different groups of theropods, and I remember you really dug in.

speaker-1 (03:38.152)
yeah, so I think I started with overall theropods. So theropoda literally means beast foot in ancient Greek, which I think is kind of funny because there’s a lot of like therians and things that end in theras are often mammals. The beast is sort of a beast is often associated with mammals in the phylogenetic names, but in the case of theropods, the beast foot is actually a dinosaur thing and a bird thing, because birds are theropods.

speaker-0 (04:07.33)
And they have similar feet. You can see it in the track.

speaker-1 (04:10.074)
Beastly feet. I mean, if you think of something like a griffin with a part of a body like a lion and the front half like a eagle or some other bird of prey, they often have talons in the front and that’s sort of what makes them extra beasty. So I don’t know if that’s what people were thinking of when they named the beast feet. But they do have large sharp claws on their hands and feet. Usually we’re talking about feet when we’re talking about

speaker-0 (04:29.942)
Maybe.

speaker-1 (04:38.904)
theropods and their beast feet, but sometimes they do have four legs, in which case the front legs would have the claws. In the most cases when they’re bipedal, they usually have pretty big claws on their hands too. Even things like T-Rex had some pretty decent claws on those little tiny fingers. Some of the first known dinosaurs are theropods. So not only are they the only dinosaurs that are around today as birds, they were also some of the first dinosaurs

The oldest ones we have are about 230 million years old. Sometimes you could say about 240 million years old, depending on how you classify things like Niaosaura. It’s one of those things where it’s like, is that a theropod? Is it a theropod like basal dinosaur or dinosaur form or dinosaur morph? Yeah, and it’s really just a question of it’s like a semantic thing.

speaker-0 (05:28.456)
Hard to tell in the early days.

speaker-1 (05:33.858)
They were definitely around by the midpoint of the Triassic, which again is the late Triassic, confusingly. There are some cool basal theropods like Eodramaeus, the Dawn Runner, and that sort of indicates that they were usually these bipedal quick forms, basically for the last 230 million years. At least there were some of them around. Not all theropods are quick.

Some of the first well-known theropods are psylophysoids. Those evolved later in the Triassic, about maybe 220 million years old. But when you get to the early Jurassic is when you get the exciting stuff starting to pop up.

speaker-0 (06:15.406)
That’s biased.

speaker-1 (06:17.646)
I I mean they’re the ones, the groups that we’re the most familiar with, like tetanurins, which means stiff tails, and that’s a lot of the more exciting big dinosaurs, big theropods like T-Rex and dromaosaurs, and a lot of people’s favorite meat-eating dinosaurs. Ceratosaurs are typically seen as a sister group to tetanurin, so they are not the stiff-tailed in air quotes one, even though some of them had fairly stiff tails. Mm-hmm.

In the Triassic, a lot of the theropods had five fingers, but by the Jurassic, both the ceratosaurs and the tetanurins had lost their fifth metacarpal bone, the hand bone, which means there was no place for a fifth finger in any of those cases. So they had a maximum of four fingers. Although, of course, we know that a lot of theropods had just three fingers, and in some cases only two fingers, like or duonicus.

speaker-0 (07:09.656)
yeah.

speaker-1 (07:13.558)
One of the things that sets Ceratosaurs apart superficially from tetanurins is that a lot of Ceratosaurus had fancy head ornamentation, like the horns you see on Ceratosaurus, and that Sarah part of their name is where the name comes from. It’s the same as Triceratops, the three horns. So it’s about the horns, basically, with the name Ceratosaurus, even though not all Ceratosaurus had horns, and some tetanurins did have some fancy head ornamentation too.

Maybe the three biggest groups within the tetanurins that we usually talk about are the allosauroids, the tyrannosauroids, and the manoraptorins. So allosoroids were basically the first large apex predatory dinosaurs. Yeah. Dilophosaurus, I think you could consider another early large predator. It’s from the early Jurassic.

speaker-0 (08:00.833)
Allosaurus.

speaker-1 (08:10.048)
It’s not either a ceratosaur or a tetanurin. It’s just sort of a basal neotheropod, but it had kind of a flimsier head and it was sort of a one-off in the fossil record. It’s not a part of a larger group, and it’s really a lot smaller than Allosaurus was. But those allosaurs first showed up in the middle Jurassic, maybe about 170 million years ago. Like ceratosaurs, many of them had horns or other ornamentation on their heads.

Although I do think the Ceratosaurs like Carnotaurus had more impressive head ornamentation. I think Carotaurus might have the most impressive head ornamentation of really any predatory dinosaur. Those big horns, it just looks so ferocious.

speaker-0 (08:55.342)
What about Majungasaurus with the horn on top of its head?

speaker-1 (08:58.166)
Yeah, but I don’t know. Something about the pair of horns, maybe it just has to do with like Christian iconography of like bulls and goats and things with like sort of the devilish demeanor. And it also has such a tall head that it gives it just sort of a fierce look to it. And also most of the paleo art of it, a lot of times it’s depicted as like red and black and I don’t know. It just looks intense.

speaker-0 (09:20.684)
I like the ones that have the ridges over their eyes that are like sun shades.

speaker-1 (09:24.556)
Yeah. That’s true too. Giganotosaurus is another famous allosoroid, one of the largest theropods to ever live. Its skull was about one point six meters or five foot four inches long, which is actually larger or longer, I should say, than the head of a T Rex.

speaker-0 (09:41.72)
Hmm, speaking of those ridges. Yes. Which do look intense, especially on such a large head.

speaker-1 (09:46.83)
But in favor of T-Rex, Giganotosaurus did not have as robust of teeth or as high of a bite force. One thing that’s interesting about allosauroids is there are a lot of bone beds that have many allosoroids together, and unlike tyrannosauroids, they tend to not have frequent bite marks on their skulls. So it’s possible that they Yeah, they were nicer to each other, or maybe they lived in social groups more often.

speaker-0 (10:09.474)
Nicer to each other.

speaker-1 (10:15.712)
It could also just be that allosauroids weren’t as intelligent and got caught in predator traps more often or something. Or they were just more populous, so their bones are more common. But allosauroids went extinct roughly halfway through the Cretaceous. Some of that was probably due to competition with tyrannosauroids, but it’s not that simple. It’s never that simple. For example, there were no tyrannosauroids, unless you include Megaraptora in South America, Africa, or Europe.

But allosauroids still went extinct in those places. So it might have to do with their food, which might have to do with their food’s food. One of those things where like maybe plants changed, that changed the herbivores, and maybe the allosoroids weren’t well adapted for that prey anymore. And something else took over. Specifically in those cases, ceratosaurs were often the thing that took over from the allosoroids. But in a lot of places, tyrannosauroids did take over, and tyrannosauroids are pretty cool.

One of the things that makes them so unique is their huge eyes. Tyrannosaurus probably had the largest eyes of any animal ever to walk the earth. Yeah. It also had some of the biggest and most powerful teeth and jaws, very good sense of smell. The one thing that wasn’t very impressive on tyrannosauroids were their arms.

speaker-0 (11:19.98)
Very good vision.

speaker-0 (11:31.924)
We’ll get into that. These new studies are pretty interesting.

speaker-1 (11:37.664)
Yeah. But despite not being all of that closely related to birds, there were members of Tyrannosauroidea that had feathers like Eutyrannus. And that brings us to Manoraptora, the last tetanurin group.

speaker-0 (11:55.448)
Yeah.

speaker-1 (11:57.71)
Yeah. Interestingly, Mana Raptora, the name means seizing hands, because they often have long arms, long fingers, and flexible wrists. And all of those characteristics would be good for snatching prey with big, thinking like slender man hands. But it also turns out that those are things that you want if you have wings. So Mana Raptora might be kind of a strange name. The seizing hands might have been more of a flying hand situation.

speaker-0 (12:27.342)
Well, they definitely didn’t all fly.

speaker-1 (12:29.516)
Yes, that’s true. But some of the ones that inspired the name, I think, probably had wing membranes on those fingers, especially the ones that had the flexible wrist, because that seems to be a later adaptation towards folding the wings by their sides. Manorapterins include ovaraptorosaurs. They have toothless beaks and feathers, presumably for brooding their nests, but maybe not for flying. Yeah.

There were the ornithemimosaurs, the ostrich-like dinosaurs. There were also the thterosinosauroids, the longest claws of any animals ever to live. But the They were seizing plants with those big hands. There are the alvarasaurids, the ones that had really tiny hands. It’s kind of funny to say that they would ever seize anything with their little weird chest claws. Big They were, but definitely not seizing, maybe breaking things.

speaker-0 (13:05.198)
Plant eaters.

speaker-1 (13:24.578)
There were the dromaeosaurids, also known as the raptors. They I guess might have seized some things with their hands, although a lot of times they’re depicted with feathers, which make it a little more difficult to use a hand when it’s more wing-like.

speaker-0 (13:39.948)
It might have helped them while they were seizing with their feet.

speaker-1 (13:42.488)
That’s true. They could be the seizing feet. Then there’s of course the avialins or the bird wings, which eventually evolved into modern birds. And that’s definitely the biggest group of Manoraptora by a wide margin because there’s over ten thousand species of them alive today, let alone in the fossil record.

speaker-0 (14:01.23)
So there we go. We’ve gone over a lot of the different groups of theropods. Yeah. Now that we’ve done that recap, we’ve got a new study that tells us more about how theropods evolved. So there is a new early Jurassic theropod skeleton that gives us more insight into how theropods evolved. This was published in the zoological journal of the Linnean Society by Ron Wei Wong and others, and this is a new study.

speaker-1 (14:05.368)
Some of the greatest hits at least. Yeah.

speaker-0 (14:28.43)
Specifically, it’s a partial skeleton of a non-Avi Rostra neotheropod. And Avi Rostra includes nearly all theropods from the early Jurassic to the Late Cretaceous, and they gave rise to birds. It also includes ceratosaurs and tetanurins. Good thing we just went over those groups.

speaker-1 (14:47.51)
Yeah, so that’s basically similar to Neotheropada, you can say Avi Rostra. I think the only difference is that Neotheropada also includes the coelophysoids. So basically it’s all of the theropods from the Jurassic onwards, except for coelophysoids and a couple other exceptions.

speaker-0 (15:08.622)
Well, so based on this specimen, they named a new clade, Avi rostraformes, and that includes all neotheropods more closely related to Allosaurus than Coelophysis.

speaker-1 (15:20.546)
Okay, yeah. So sort of excluding Celophysis, but o every other theropod almost.

speaker-0 (15:27.774)
The neotheropods, yeah. And they described this new specimen. It’s a partial skeleton of an immature individual. It’s only missing its neck and backbones. And it’s got a unique combination of characters, although there’s no overlapping fossils with a theropod that lived around the same time and place. That theropod is called Schwangbisaurus. So they couldn’t compare those and they didn’t name a new dinosaur.

speaker-1 (15:51.928)
Wow, look at them exercising restraint not naming new dinosaurs when they’re pretty sure they got something new.

speaker-0 (15:55.33)
Yes.

speaker-0 (15:59.47)
But they found it was a sister taxon to Avi rostra and it helped show this transition. They found some features that were thought to belong to tetanurins that it turns out it evolved earlier because it had advanced air sacs or skeletal pneumaticity in the skeleton, which was a feature thought to evolve later.

speaker-1 (16:18.098)
that’s a big change. Yeah. It could be a point in favor of sauropods and theropods staying in Soriskia together too, depending on how you interpret it.

speaker-0 (16:28.27)
Maybe they’ll find more fossils and name it.

speaker-1 (16:30.358)
Yeah. Although it like they’re I think presuming this might just be Schwang Bisaurus because if it’s from the same time and place and they’re both theropods to all that.

speaker-0 (16:42.555)
there can be multiple theropods in the same time and place.

speaker-1 (16:46.07)
Yeah, that’s true. Just ask Stromer.

speaker-0 (16:50.36)
Alright, so now on to our new dinosaurs. I’m talking about some of the smaller theropods, a couple of Mesozoic birds, specifically in antiornithines. And in antiornithines are those opposite birds. They were usually small, they usually had teeth, and they were covered in feathers.

speaker-1 (17:06.2)
Hm. Even though they’re the opposite birds, I think of them as the toothed birds.

speaker-0 (17:11.744)
Well, a lot of them did have teeth, but not all of Yeah. So this new antiornithene is Plumadraco Bancurum, and it had really long tail feathers. Mm. This was published in PLOS one by Alexander Clark and others. And antiornithines were the most diverse group of birds in the Cretaceous. There’s over a hundred genera described so far, and they’re from all continents except Antarctica. Some of them have been found with soft tissues, mostly feathers. And in this case

The feathers of pluma Draco, the tail feathers, are twice as long as its body.

speaker-1 (17:46.176)
man. Yeah, that picture is crazy.

speaker-0 (17:49.15)
Yeah. And the tail ends in proportionally small, pinaceous rackets, rigid, interlocking feathers. So the two very long tail feathers, I’d say they look like strings or ribbons, and then the end of them look like what I picture a typical feather shape is if you were to draw a feather. Mm-hmm.

speaker-1 (18:09.336)
Yeah, just really long skinny feathers sticking out of its tail. Yeah. It almost reminds me of like a tuning fork or what’s the instrument? There’s an instrument too that’s sort of a V shaped like that too, where you like I don’t know. Run a stick on it or something. But yeah. Or maybe two really long chopsticks.

speaker-0 (18:30.51)
Chopsticks seem too rigid because these are built or shaped in a way that it could have these flickering motions. Makes sense, they’re feathers.

speaker-1 (18:36.454)
Ooh, that’s pretty. Yeah. I guess just ’cause they’re preserved in a slab sort of smash down and they look c stiff in their fossilization when they’re stuck in rock. Right. But yeah.

speaker-0 (18:49.646)
But when it was alive, it wasn’t like that. And it could probably pump its tail up and down. So it’s possible it had this tail for courtship displays. Cause this tail feather would incur drag, so it would not have been good for flying. It was likely more for showing off or communication purposes. This could also be a case of sexual dimorphism, because that’s been established with other early Cretaceous birds, like with Confucius Ornis, where multiple specimens with soft tissues have been found. This type of tail is in

speaker-1 (18:51.906)
Make sense.

speaker-0 (19:19.256)
forty to sixty percent of individuals, which is what you’d expect for sexual dimorphism. Mm. So it seems likely that this particular specimen is male.

speaker-1 (19:28.94)
Yeah. Usually they’re the ones with the showy feathers. It also kind of reminds me of the resplendent Quetzal. I don’t know if they made any analogies to that, but that’s what Quetzal Coatlas is named after. And it’s it’s this bird that’s found in Central America and it’s got two really long tail feathers to the point where it makes it hard for it to fly. And they do that swooshing motion that you were talking about. They’re also much longer than their body, their f tail feathers.

speaker-0 (19:56.716)
It does seem like it could get in the way. Mm-hmm. So yeah. This specimen being male is also based on the hypothesis that an antiornithene had nests on the ground and the females took care of the nests, so they would have needed to blend in more, not have these flashy tails that might get in the way. And and antiornithines are considered to be precocial from birth. They can take care of themselves early on, so the males don’t need to be involved and they can focus more on attracting the mates, the earlier process of the the cycle.

speaker-1 (20:27.01)
Yeah. It is funny. I was I’m just looking at pictures of the resplendent cat’s owl and there is a picture of a male taking care of its nest, even in its bright green colors. And it’s made a nest inside a tree. So it’s just got a little hole in a tree, but its tail feathers are so long that they’re actually poking out like over its back and sticking out past its head. Like the tail feather can’t fit in the tree. So it’s just making it extra obvious, like waving a flag like, Hey, I’m over here nesting.

speaker-0 (20:56.67)
Yeah. That doesn’t seem like the best thing. No.

speaker-1 (21:02.174)
But it wouldn’t have been able to make that nest without impressing a mate. So that’s why a lot of those features evolve for impressing mates over everything else.

speaker-0 (21:11.566)
So Pluma Draco is from the Jehol biota. About 120 million years ago. It was found in the Liaoning province in China. The genus name Pluma Draco means feather dragon. Yeah. Very fitting. Yeah. And the species name Bankuram is in honor of Winston E. Paul C. Banco. The author said, quote, together their momentous lifelong efforts have significantly contributed to our understanding of avian biology and conservation.

speaker-1 (21:25.838)
Plumage.

speaker-0 (21:40.504)
Particularly across the Hawaiian archipelago.

speaker-1 (21:43.768)
Wow, that’s cool. Not a place named Saurus or place named Encis. Mm-hmm. That’s what I like.

speaker-0 (21:50.19)
And the holotype, like you were saying, it’s on a slab. It’s a complete articulated skeleton in the single slab, and the feathers are preserved around the head, body, wings, and tail, although some parts are crushed or not well preserved. And this is a mid-size specimen. It’s about 112 to 144 grams. They’re estimating it weighed.

speaker-1 (22:10.988)
Okay. So that’s like a quarter pound. Yeah. But in terms of birds today, it’s like kind of typical for like a songbird or something. Mm-hmm. And this one did have teeth. I just double checked. They said there were five preserved teeth in the right upper jaw, which are so small that if it wasn’t for their drawing pointing them out, I would not notice that those were teeth.

speaker-0 (22:15.466)
Very small.

speaker-0 (22:36.76)
Focus is on the tail feathers.

speaker-1 (22:38.638)
But they have a whole skull there too. Yeah. And it’s an enantiornothine, so we gotta figure out if it had teeth or not.

speaker-0 (22:46.412)
All right, we’ve got another new antiornithene. This one is Gorgonavus Alcyani. This was published in the Swiss Journal of Paleontology by Sergio Nebretta and others. It lived in the early Cretaceous and what is now Cuenca, Spain. They found a partial skull, which includes parts of the brain case, beak, and lower jaw, that was exposed in the surface of a limestone slab. And that area is known.

For a lot of fossil birds. It’s actually the best place for early Cretaceous inantiornithine birds outside of China. This is the La Uarguina formation. So this inantiornithine, it’s the first non-juvenile skull bones of an avialin found in the early Cretaceous of Europe, what’s now Europe. It’s likely part of the family Longterygidae, which is a family only definitively known from China. The type species is Gorgonavus alcyanee.

The genus name means Gorgon bird, and it refers to the gorgons of ancient Greek mythology, which could turn people to stone by looking at them, think Medusa. Mm-hmm. That’s based on only an isolated skull being found. And then the species name, Alcyone, is also from Greek mythology. Alcyone and her husband often called each other Zeus and Hera, which angered Zeus. So he killed the husband, and then when Alcione learned what happened, she threw herself into the sea, and the gods changed them both to

Halcyon birds or kingfishers, and kingfishers have a long beak similar to Gorgonavus. Gorgonavus’s skull is about 1.2 inches or three centimeters long. The bones are fused, so likely it was skeletally mature or fully grown, and it had this long, slender beak, and it had teeth in its premaxilla in the front of the snout or the beaks, an anti ornithine with teeth. But the maxilla is toothless or endulous, so the rest of the beak has no teeth.

speaker-1 (24:33.75)
Nice. That’s how I like them.

speaker-0 (24:40.174)
In the Paleo Art, it looks to me kind of like a kingfisher. It’s got the long beak and it’s small but with bigger eyes and a longer tail, although you can’t beat Pluma Drago’s tail. So first in Antio Arthine had long tail, and then this one I would say had a long beak.

speaker-1 (24:53.816)
Although we don’t really know much about its tail anyway, because it’s n just known from a skull. So they’re just sort of winging it, one might say. With the rest of the body. I like that. They really leaned into the Greek mythology with that naming. That’s pretty cool. Mm-hmm. And also impressive that they managed to cause Gorgonavis is an easy name to say. There are a lot of an anti-unor things that have been named to end.

speaker-0 (24:59.19)
That’s true.

speaker-0 (25:03.875)
Yeah.

speaker-0 (25:08.184)
Mm-hmm.

speaker-1 (25:23.51)
A lot of times they’re doing deeper cuts to get something that’s Latin or Greek. But yeah, gorgons are always a good place to start.

speaker-0 (25:32.974)
So on the other end of the theropod spectrum, we’re going from small theropods to large, paleontologists have found an extra large tyrannosaur shin bone in New Mexico, which may show that tyrannosaurus evolved in North America. Yes, this was published in scientific reports by Nicholas Longridge and others, and it’s a new study. The isolated tibia or shin bone is from 74 million years ago. It was in the Kirtland formation in what’s now New Mexico.

speaker-1 (25:47.31)
Yeah.

speaker-0 (26:02.04)
That tibia is about 37 inches or 96 centimeters long and five inches or close to 13 centimeters across. And that’s about 84% the length and 78% the width of Sioux, the tyrannosaurus’ shin. And Sioux is the largest known T-Rex. This tyrannosaur is estimated to weigh about 10,000 pounds or around 4700 kilograms.

speaker-1 (26:25.208)
So five tons compared to I think Sioux is estimated at like eight or nine.

speaker-0 (26:29.494)
Something like that, but Sue lived way more recently. Well maybe not way, but more recently.

speaker-1 (26:32.268)
Yeah, yeah. Yeah, I w I’d say way more recently, like five, six million years, that’s a long time. Yeah. There’s no chance that they overlapped in age, even with big error bars.

speaker-0 (26:45.132)
And for this tyrannosaur, it’s got a straight bone shaft. It’s a robust straight leg bone and a unique triangular shape at the lower joint. So there’s a few possibilities of what it could be. It could be an unusually large bistahe versor. That’s the only known tyrannosaur from the same area where this fossil was found. we talked about it back in episode four hundred and seventy-eight. It’s a large tyrannosaur lived in the Lake Cretaceous in New Mexico. It had a big head with a deep skull, but it doesn’t have that triangular shape near the foot.

So another possibility is if it’s a new previously unknown lineage of giant tyrannosaur, or an early representative of tyrannosauriani, which seems likely based on the features of the bone that it’s an early member of Tyrannosaurinai, and that would show that they evolved earlier than we previously thought. So this would make it the oldest known giant tyrannosaur from North America, maybe the oldest known member of the group that includes Tyrannosaurus and Tarbosaurus, which is Tyrannosaurini.

speaker-1 (27:43.82)
Yeah. Yeah, those tyrannosaurenes. They are the most tyrannosauri of the tyrannosaurs, at least the closest members to tyrannosaurus, which is usually what people want to think about when they’re thinking about tyrannosaurs. Yeah. That’s pretty cool. Yeah, we’ve talked about how tyrannosaurus even might have lived across most of North America, or at least most of what’s now the US and southern Canada. So it would make sense that.

Some of the recent-ish ancestors before Tyrannosaurus would have also lived in North America. I don’t know about the whole, did it evolve first in North America or Asia? It’s just it goes back and forth every time one of these discoveries happens.

speaker-0 (28:28.878)
I think that’s gonna be something debated for a while.

speaker-1 (28:31.284)
Yeah. And then it just becomes that thing we always talk about, like where do you draw the line between tyrannosaurenes versus just tyrannosaurus in general? But yeah, everyone wants bragging rights for the first close relative of Tyrannosaurus, since everyone loves Tyrannosaurus.

speaker-0 (28:48.396)
This does seem to be a big one. Big tyrannosaur.

speaker-1 (28:51.49)
Yeah, I appreciated the comparison to Sue’s shin bone, or I guess tibia, because I know about the femur size, but I don’t keep track of the tibia size.

speaker-0 (29:02.894)
We’ll talk more about tyrannosaur theropods in just a moment, but first we’re gonna take a quick break for our sponsors.

And now we’re going back to small theropods, but we’re sticking with tyrannosur theropods, specifically nano tyrannos. So there you go, that’s the ultimate small tyrannosaur.

speaker-1 (32:24.27)
Yeah, I was gonna say at least by name, it’s the small sounding one.

speaker-0 (32:29.314)
There’s a new study that found a bone that supports the tongue is further evidence that Nanotyranus is a valid dinosaur. This was published in science by Christopher Griffin and others. And this study was going on at the same time as the other study that found Nanoturanus was valid. It was published like a month apart, and but it’s just more confirmation about nanotyranis.

speaker-1 (32:49.58)
Like those independent lines of evidence from independent researchers. Yeah. Makes it more likely.

speaker-0 (32:54.84)
So usually paleontologists cut open a femur or rib bone to look for lags. Lags, lines of arrested growth are like tree rings. You can count how old an individual dinosaur was. But turns out you can do the same thing with a hyoid bone. Yeah, they’re hyoids are the small straight bones that run beneath the jaw and support the tongue, and they’re two separate bones. It’s helpful if you don’t have a femur or a long bone, which is the case for the holotype of nanotyranis.

speaker-1 (33:04.29)
Yeah, approximately.

speaker-1 (33:08.75)
speaker-1 (33:23.854)
‘Cause it’s basically a skull. But there’s a hyoid one in there. That’s cool. Yeah.

speaker-0 (33:29.484)
And they show growth rings. They’re widely spaced for juveniles. They’re closer together for adults, the growth rings. You can see that same pattern in a rib bone or femur. And again, that’s what you usually cut into. The small skull of Nanotyranus lancensis was found in 1942. And of course, that was all that was found of that specimen. So what they did was they cut into it. They did histology. And they found that it had reached near skeletal maturity, meaning it was an adult. Then they built a database of hyoid and longbone measurements for comparison.

Which is good because then you can use that for future studies. For reference, the nano tyrannicus skull is about twenty-two inches or fifty-seven centimeters long. Tyrannosaurus skulls are more around four to six feet or one to two meters long.

speaker-1 (34:11.446)
Yeah. Yeah. And the adult ones are yeah, closer to two meters. Not quite two meters, but you we’re definitely talking like five feet. Yeah. Sixty inches, which is what, about three times the length of this. And if you do it by mass or bulk, way bigger. I’m a little bit surprised that they let them cut into their beautiful holotype nanoteramus skull.

to do the destructive testing on a hyoid bone, which are already kind of rare. But it’s nice. It’s nice to have the results. So I guess maybe they eventually convinced them. Maybe they got I didn’t look through the whole author list to see, but I suspect that whoever convinced them to do this has some affiliations with the museum and didn’t just walk in off the street and say like, hey, I want to cut open your mission. Yeah. yeah. I see the

Second author on the list is at the Cleveland Museum of Natural History. So he must have been the one that gave the okay.

Since that’s where the holotype is.

speaker-0 (35:18.712)
Speculation, but it does seem likely.

speaker-1 (35:20.62)
Yeah, there’s some other authors on there too that are also from the museum.

speaker-0 (35:24.3)
If you want to hear more about how Nanotyranus is valid, we talked about it a lot in episode 554 titled Nanotyrannis is valid, where Lindsay Zano and James Napoli found that it’s its own genus. It’s not a juvenile Tyrannosaurus Rex, and they also named a second Nanotyrannus species. And they were able to do this by looking at a few Nanotyrannis skeletons, especially the Bloody Mary specimen.

Which is part of the dueling dinosaurs. It’s found preserved in Tangle with the Ceratopsians. That’s pretty cool. And they settled a debate that had been going on for like forty ish years.

speaker-1 (36:01.442)
Yeah, even longer if you include when it was Gorgosaurus Lansensis. yeah.

speaker-0 (36:05.248)
yeah. All right. Now on to the meaty stuff, and by that I mean what made it possible for theropods to go for the meaty stuff.

speaker-1 (36:13.838)
Their adaptations for carnivory.

speaker-0 (36:16.598)
Yes. How and what theropods ate changed over time as their skulls evolved, and theropods with skulls that had low stress on them while feeding could go after bigger prey. This was published by Evan Johnson Ransom and others in the Anatomical Record and it’s open access. And thank you to Evan for sharing this study with us. It did come out way back in January. I was just waiting until our next theropod episode to talk about it.

speaker-1 (36:44.046)
Yeah, Evan did his thesis back in graduate school on basically this, not just Tyrannosauroidea. He I believe had some other Yes. Yeah. And basically looking at these stress versus strain models, computer models on skulls to see how hard could they bite without their skull breaking. And that’s sort of the upper limit for how hard they could bite. Doesn’t necessarily mean that they had the musculature to do that hard of a bite.

speaker-0 (36:54.296)
Dinosaurs too.

speaker-1 (37:13.506)
But in general, animals don’t like reinforce their skull for a super strong bite to resist all the stress and strain because that takes extra muscle and extra energy to create if they’re not going to use it.

speaker-0 (37:26.04)
Yeah. So first I want to quote from the paper. They said, Tyrannosaurus is viewed as a model organism in vertebrate paleontology, end quote. And it’s because there’s a lot of well-preserved fossils and there shows a lot of variation. And within tyrannosaurs or tyrannosauroids, you’ve got the small early tyrannosauroids with the flattened blade-like teeth and long arms, and then you got the large tyrannosauroids with the deep skulls, the short arms and the big teeth.

speaker-1 (37:34.296)
Yeah.

speaker-0 (37:53.166)
For this study, they used muscle force reconstruction and finite element analysis, or FEA, to quantify the strength of tyrannosauroids and other theropod skulls for feeding, and then they analyzed how feeding changed over time.

speaker-1 (38:06.52)
It’s nice that they reconstructed some muscles and didn’t just look at the strength of the skulls on their own.

speaker-0 (38:13.282)
Yeah. They found that tyrannosauroids had moderate to low stress on their skulls or cranial stresses were low. The hypothetical common ancestors in tyrannosauroids had low cranial stress from a combination of having robust skulls and bumps on the skulls to help. And they may have passed that down to later tyrannosauroids, and then those later tyrannosauroids could handle high forces. It’s possible there’s a correlation between the shape of the skull and how they ate.

So predators have all different features to help them go after prey. Some large crocodilians have rows of conical teeth to hold down the prey and drown it. Carnivorous mammals have heterodont teeth, that’s just a number of different types of teeth for puncturing, holding, slicing, cracking. Then you’ve got like toothless birds, they have talons and sharp beaks. When you compare body sizes, jaw features, feeding behaviors, and ecologies of living animals, you can use that to predict how extinct animals like large theropods

may have eaten and lived. And we know pherpods came in all shapes and sizes. The non-avian ones include the short faced abellosaurs, the crocodile snouted spinosaurs, and of course those deep snouted tyrannosaurs. yeah. Tyrannosaurus as an adult had a reinforced skull to help it eat, because it had a strong bite force with robust teeth, and it had fused and immobile bones to strengthen its jaw for biting, as well as powerful neck muscles for removing flesh.

Trace fossils support that it had this puncture pull way of eating, where it would bite into prey, pull back its head, and drag its teeth through the meat. Oof. And we know a lot about how tyrannosaurus ate, but less so when it comes to its relatives. So they had a few hypotheses going into the study. One was that grassile snouted tyrannosaurs like Alluramus or Chingosaurus, that’s the Pinocchio Rex, as well as smaller tyrannosaurs, had higher stress on their skulls compared to deep-snouted tyrannosaurs.

When you were comparing them to a standardized force. They also hypothesized that the same thing happened with grass isle-snouted non-tyranosauroid theropods, think spinosaurs, carcheridontosaurus, dramaeosaurs. The next hypothesis was that crests of theropods, like Guanlong and Dilophosaurus, acted like a buttress or reinforcement when biting so that they could handle higher stress.

speaker-0 (40:29.932)
And the last hypothesis was that as tyrannosauroids evolved and got larger, the cranial stress decreased relative to their skull length, so they could have stronger bites or higher bite forces. For this study, they included a lot of groups. They had coefficids, dilophosaurids, ceratosaurs, megalosaurs, allosaurs, manoraptors, compsignathids, and tyrannosaurs. There were some limitations. They said they had to do 2D and 3D models.

Partly based on which fossils have been found. Like if it wasn’t complete enough, they could only do a 2D model instead of a three D one. Okay. But three D models were more realistic for stress magnitudes.

speaker-1 (41:04.14)
that’s nice. I think Evans thesis was mostly two D. Mm. And I remember at the time saying like, well, three D the skulls are in three D. Yes. And it takes a lot more computing power to do three D. Yeah.

speaker-0 (41:13.294)
He’s just getting started.

speaker-0 (41:19.086)
So they found that subadults like Raptorx and slender snouted tyrannosaurs like Changosaurus had higher stress on their skulls compared to deep snouted tyrannosaurs. There is some controversy with Raptorex. The latest study about Raptorex by Gormran and others, which was published in Cretaceous Research, found that Raptorx and Asia Tyrannus were junior synonyms of Tarbosaurus. So just keep that in mind. For Evan’s study and his team,

They found that spinosaurs had higher stresses than abellosaurs and large carcaridosaurs. And their results support the hypothesis that as the length of the skull increased, and the length of the skull is a proxy for body size, so another way to put it is just as they got bigger, the level of stress on the skull decreased.

speaker-1 (42:03.032)
Hm, except with some exceptions like spinosaurs.

speaker-0 (42:06.474)
Yes. Well, this is for that first hypothesis that the deep snouted tyrannosaurs could handle the stress better. Had higher stress, yeah. They found that theropods with crests like Dilaposaurus need more analysis, including what’s going on inside those crests, those internal crest structures.

speaker-1 (42:14.637)
See.

speaker-1 (42:26.478)
Yeah, ’cause if they’re hollow, like the recent papers were suggesting, they’re not gonna be able to carry much load.

speaker-0 (42:32.728)
Yes. But they might have played a role in reducing the stress on the theropod skulls that had the crests. They found that when they excluded the crests from the study, the amount of stress was either the same. They saw this in Guanlong, or it increased. They saw this in Dilophosaurus. So it seems like maybe it did something.

speaker-1 (42:50.008)
It’s not gonna hurt. Yeah.

speaker-0 (42:51.938)
Not many medium sized tyrannosauroids from the mid-Cretaceous have been found, and they may be important to see how tyrannosaurs evolved to feed. They found that the levels of stress didn’t necessarily go down as the head size or length increased. Some small theropods had more robust skulls compared to similarly sized theropods. Now, looking at the stress levels of the skulls and studying them, they were able to infer the feeding behavior and paleoecology of the theropods in their study.

speaker-1 (43:20.27)
So in other words, what they ate and how that impacted their ecosystem.

speaker-0 (43:25.614)
Exactly. Non Avi rostran theropods, early ones like Coelophysis, had low stress on the skulls and maybe ate animals similar to its size or smaller. Coephysis had long arms and hooked hand claws, so that would have been good for grasping smaller prey. Dilophosaurus had low stress and a robust skull, so it seems like it had a forceful bite. It had strong, flexible arms, and it could grip and hold things between its two hands, and then with one hand bring an object close to its mouth. Could also swing its arms in an arc and scratch its belly.

Do a lot with its arms.

speaker-1 (43:56.846)
The belly scratching is a a feature of dinosaurs that we don’t usually highlight. Yeah.

speaker-0 (44:02.894)
Now, Ceratosaurs like Ceratosaurus and Mechikosaurus had high stress compared to abellosaurus. So Ceratosaurus may have had a weak bite force and then used its large sharp teeth to quickly slice and rake flesh. And it lived alongside larger theropods, so it may have avoided competition by going after smaller, maybe more aquatic prey than other theropods in the Morrison formation, and maybe it also scavenged larger animals.

speaker-1 (44:29.654)
Depending on who you ask, Mechikasaurus had some pretty freaky teeth. yeah. Which do look like fish biters.

speaker-0 (44:36.994)
But maybe to grasp smaller prey and cut and slice. It probably couldn’t really tear the larger food apart though.

speaker-1 (44:43.384)
Yeah, those teeth don’t look like tearing.

speaker-0 (44:45.602)
Yeah. Abellosaurs had low stress, so they likely went after large prey like sauropods. Megalosaurs like Torvosaurus had low stress in the skull, but higher stress in the jaws. They might have also been able to go after big prey like stegosaurus and sauropods. Spinosaurs had low stress, except for baryonics. Spinosaurus and sucumimus could eat things other than fish, although they didn’t have as forceful of a bite as other theropods. Spinosaurs likely had big neck muscles to help them.

strike quickly and withdraw their head rapidly. So it’s likely they ate large fish, small dinosaurs, and pterosaurs, and we’ve seen examples of all this in gut contents of Spinosaurs.

speaker-1 (45:24.312)
So the spinosaurs had higher stresses than abellosaurs and large carcarodontosaurs, but lower stresses than megalosaurs and some of these other theropods, it sounds like. They’re kind of in the middle.

speaker-0 (45:38.114)
Yeah, I think so. And then allosaurs had low stress and they could go after large prey like sauropods, but their bite forces were lower compared to tyrannosaurs. They had high stress and an equivalent force to the tyrannosaurs.

speaker-1 (45:51.348)
I see. So if you scale it down for the size of their head, they it was their head wasn’t as well equipped for those higher stresses. Yeah. Those higher forces. Yeah.

speaker-0 (46:01.198)
But then when you’re trying to compare it to other theropod skulls, you want to give it all the same force. Megaraptors had low stress. They may have gone for small prey like small ornithopods and large animals, also, like large ornithopods and titanosaurs. Based on their anatomy, megaraptors were likely active predators, and they have the long arms, so they could also grab the smaller animals easily. Compsignathids had low stress, although the paper acknowledged about

Compsignathids recently being found to be juveniles or small individuals of other theropodquades, which we’ve talked about on the show.

speaker-1 (46:34.742)
Yeah. Are they all just babies of other things?

speaker-0 (46:37.406)
Right. Compsignathus probably ate smaller animals, but larger ones like Sinocaleopteryx may have eaten prey their size or smaller, and could probably hunt agile prey, including birds.

speaker-1 (46:50.254)
It would be interesting if they turned out to be babies and we could figure out what they were babies of. Yeah. And then it just becomes like Sinocalyopteryx is the baby such and such. Yeah. And we know what it might have eaten based on this study.

speaker-0 (47:01.486)
Exactly. Now dromaeosaurs ate all kinds of prey. They had high stress, so they used their sickle claws more than their jaws as their weapon. Makes sense, I’m not surprised by that. And Trodontids were likely omnivorous, which we have also talked about in our show. Smaller tyrannosauroids like Dilong and juveniles like Raptoracs didn’t have as high of bite forces as adults, so they likely went for smaller animals and prey similar to their size. And small early tyrannosauroids like Guanlong would have been

General carnivores. Medium-sized tyrannosaurids like Tyrantophonius and Chingosaurus in general had lower stress than smaller tyrannosauroids. Some went for smaller prey and some went for larger prey. And then larger tyrannosauroids, especially those deep snouted ones, had lower stress and they could go after lots of large prey: Ceratopsians, hadrosaurs, ornithumimosaurs, sauropods, larger tyrannosaurs. You can think of tyrannosaurs and tarbosaurus, for example, and they were apex predators.

speaker-1 (48:00.93)
Yeah. If Tyrannosaurus could find a sauropod, which jury’s still out on whether or not Alamosaurus or something even made it to the Hell Creek. Yes. But I guess that agrees with previous papers that we’ve talked about. The the smaller theropods probably went after smaller prey. The medium sized one, it was a mixed bag, but in general still going after smaller prey. And then the it was really the large tyrannosaurs, especially, but some of the other large theropods

That could go after the really big prey.

speaker-0 (48:31.426)
Yeah. Which we I think the last time we really talked about it was episode five hundred and fifty-two, what dinosaurs ate. There was a study that looked at like eighteen species of theropods and their bite strength. And they found like tyrannosaurs had the skulls built for crushing bones, but then megalosaurs and allosaurs had skulls that were good for slicing through prey. Mm-hmm.

speaker-1 (48:52.684)
Yeah. So not only that analysis was more looking at the musculature, and this one was looking at well, could the skull even handle those kinds of forces, which I guess line up with what the musculature was saying.

speaker-0 (49:04.302)
But when it comes to going after prey, it’s not just about the skulls. And that brings me to our next new study, which is pretty interesting. They found that five different carnivorous non-avian theropod groups evolved to have shorter arms and bigger heads. Yeah, not just T-Rex. And we’ve talked about that before about other theropods that had short arms, like Carnotaurus.

speaker-1 (49:19.308)
Hmm, not just T-Rex.

speaker-1 (49:28.408)
Yeah, Carnotaurus is my go to where it’s like you think T Rex had small arms for a big predator. Carnotaurus was like laughably small. At least T Rex had some claws.

speaker-0 (49:37.068)
Yeah.

So this was published in the proceedings of the Royal Society B by Charlie Roger Sherer and others. And like we’ve been saying, theropods, they lived all throughout the Mesozoic. I they’re still around today as birds. They’re all over the world. They came in all different shapes and sizes. So the question is, what drove so many groups to have shorter and shorter arms over time? Now, large meat-eating theropods likely evolved to have tiny arms because they developed their strong, powerful skulls and then they used their heads to attack prey.

As a side note, long arms would have been good for tackling smaller prey and may be related to the evolution of feathers and flight. We see this in the smaller theropods. For this study, they examined 85 theropod species. They were looking at the arms, the skulls, and the body mass, and they found that there are five groups that shortened their arms or had reduced forelimbs, which means that the length of the skull is longer than the arms.

speaker-1 (50:30.382)
That’s such a funny thing to talk about.

speaker-0 (50:34.366)
Yeah. So those five groups we’ve got tyrannosaurids, abellosaurids, carcarodontosaurus, megalosaurs, and serratosaurs. In the past, only abellosaurus, carcherodontosaurus, and tyrannosaurids were identified as having these shortened arms.

speaker-1 (50:49.014)
Yeah, megalosaurids and serratosaurids I don’t usually think of in that category. Yeah.

speaker-0 (50:56.726)
Yeah. Well, if you’re looking at individuals, you might not notice it, but if you look at them over time, you can see things change. So the small arms are more linked to having a powerful skull than to overall body size. It’s not just a byproduct of the they got bigger, so the arms got smaller. It’s more about the strength of the skull than the skull size or the body size. And prey got larger. So that may have led them the

for predators to shift to hunting using their jaws and head instead of claws.

speaker-1 (51:28.226)
It’s a good point ’cause when you were talking about Dilophosaurus and how it had pretty big hands and its skull was fairly strong, so it might have grabbed at prey and gone for things like around its size. That makes some sense. If you’re hunting a sauropod, your hands aren’t gonna do anything. Exactly. They’re completely useless.

speaker-0 (51:47.214)
I think they put that in the paper, something like that.

speaker-1 (51:49.762)
Yeah, or even going after an ankylosaur or a ceratopsian or any of these things, you’d need such huge hands for them to do anything. Yeah. At which point when you’re bipedal it’s gonna throw off your balance. So yeah, I I can see the point in just giving up on the armstring.

speaker-0 (52:06.318)
And yeah, Allosaurus and Torvosaurus coexisted with giants, sauropods, and other large prey dinosaurs. It is likely that the strong skulls came before the short arms, so that they always had some way to get food. Now, to figure out the strength of the skulls, the teen looked at things like how tightly connected the bones in the skull were, whether it was compact or long, and bite force. The highest score was unsurprisingly T Rex. And then you’ve got Tyranotitan.

Which is a Carcarodontosaurus from the early Cretaceous and what’s now Argentina. The arms in all these theropods got shorter in different ways. In abellosaurus, the hands and the lower arm got shorter. In tyrannosauroids, all parts of the arm got shorter at a similar rate. Tyrannosauroids show the clearest trend in forelimb rejection, and it seems to have happened quickly in the latest of the late Cretaceous. Each element of that forelimb just got shorter in equal proportions. They’re all getting smaller over time.

It’s not as direct that you see this with other groups.

speaker-1 (53:06.636)
Yeah, it really does just look like a shorter arm. When you look at the skeleton of a T Rex, it doesn’t look that different than our arm, other than you kinda ignore the hand. Yeah.

speaker-0 (53:15.778)
Yeah. Now some theropods had strong heads and small arms, but they weren’t that large, like Majungasaurus. And Majungasaurus and Carnotaurus have the smallest proportional values for a lot of their forelimbs. So it could be that reducing the forelimbs in later Abellosaurus was the most extreme among the gigantic carnivores. That could be because the group was around longer compared to Carcarodontosaurus and Tyrannosaurids.

The author said, quote, however, the forelimbs of carcerodontosaurids and tyrannosaurids exhibit similar degrees of reduction in the most extreme cases, suggesting that the degree of reduction is constrained by developmental pathways rather than the time allowed for reduction to occur. For some carcerodontosaurs and tyrannosaurs, they they got short arms, extremely short arms. Mm-hmm. And it could be that it wasn’t that it took a lot of time in terms of evolution to do that. Sure.

speaker-1 (54:09.592)
Catch.

speaker-0 (54:10.306)
Now, Ceratosaurus had reduced forelimbs, but it was all in the hands. It’s not a gigantic theropod, but it is close. They define gigantic theropods as a thous weighing a thousand kilograms. Ceratosaurus is estimated up to nine hundred and sixty six kilograms, so it’s pretty close. And it’s also likely there were some specimens that were larger, other than the one they used for the study. Because there is one Ceratosaurus estimated to be like 1100 kilograms or a little more.

It could be that for smaller Ceratosaurus with the short hands, it means we see this in immature specimens. We also see this with the tyrannosaurid gorgosaurus, so the reduced limbs are not just for adults. Now the results don’t fully support arms getting shorter in alvarosaurs. That’s just a a weird group of theropods. It’s partly because of their relatively small skulls and how they got smaller over time, the miniaturization trend. They’re also really specialized.

They got the hypothesis that they went digging for insects. Mm-hmm. And it seems that their arms got smaller related to going after prey. It has to do with their ecology, not their skull getting bigger.

speaker-1 (55:16.77)
Yeah, that definitely makes sense in that case, where you’re specializing on a really specific prey item that’s it’s like the size of one of your taste buds if they’re eating termites that you wouldn’t need big arms for grasping the prey at that point. They can get specialized for digging or breaking open termite nests or something. Yeah.

speaker-0 (55:35.694)
You also wouldn’t need a particularly robust skull to eat a termite. Really quick though, back to tyrannosaurs in their skulls. We talked about an example of a strong bite for us a few episodes back in episode 565 titled A Tyrannosaur Tooth Embedded in a Hadrosaur Skull. Mm-hmm. Which, I mean, that is probably the best example of a strong bite.

speaker-1 (55:58.304)
Yeah. Biting into something’s skull and strong enough that your tooth gets embedded in it. Yeah. And also the s jaw is strong enough to just break that tooth off, part of the tooth.

speaker-0 (56:09.378)
Gosh, yeah. And then that skull also had like twenty-three possible tooth marks, so it wasn’t just the one time it was going after Androsaur.

speaker-1 (56:16.364)
Yeah. We’ve got some pretty good confirmation on the T Rex end of the scale that it was in fact going after huge prey because you’ve got ceratopsians with holes that match T Rex teeth. You’ve got the said Montosaurus, which is about as big as the herbivores got in their ecosystem. Yep. So it makes sense.

speaker-0 (56:36.462)
And if there were sauropods around, it probably went after those sometimes too. But yeah, let’s not forget about the smaller tyrannosaurs. So, this next new study, actually, it’s our last study of the episode, is that smaller tyrannosaurs likely cleaned up by scavenging larger tyrannosaurs. This was published in Evolving Earth by Josephine Nielsen and others. And they studied a digital model and 3D printed replica of a partial left footbone of a large tyrannosaur.

speaker-1 (56:41.166)
Crap, boy.

speaker-0 (57:05.954)
That bone was found by an amateur fossil hunter in Montana in the Judith River Formation. It’s from about 75 million years ago. And then it was donated to the Badlands Dinosaur Museum in Dickinson, North Dakota, which is pretty cool. Nice. The footbone’s about 10 centimeters long or four inches. And the tyrannosaur that the footbone belongs to is estimated to be about 10 to 12 meters long or 33 to 39 feet long.

speaker-1 (57:17.182)
Yeah.

speaker-1 (57:28.618)
Okay, so pretty much full grown. Yeah. If not full grown.

speaker-0 (57:32.216)
They identified at least sixteen bite marks on that bone with no signs of healing. And they’re relatively small tooth marks. So it’s likely that those tooth marks are from just one tyrannosaur. They left some broad, shallow tooth marks. The bone wouldn’t have had much meat. Yeah. So it’s probably from a juvenile or a subadult, not a large individual with a reduced or weaker bite force, because the lack of soft tissue or the meat makes it unlikely that they would have done that. Mm-hmm. It could be from dyspletosaurus based on where it was located.

Displetosaurus was more common than Gorgosaurus in that formation, which is the more southern formation where they’re found. But anyway, the smaller tyrannosaur probably ate the last bits after most of the flesh was gone, which just shows it was more opportunistic than previously thought.

speaker-1 (58:17.91)
Yeah, that’s interesting. It reminds me of the paleo art from Brian Ng, where there was, I want to say it was Allosaurus. Do you remember that one? It was like chewing on the toe. Yeah. It was very metal, that drawing. I think it was Allosaurus. And then we also have talked about Majungasaurus. And the evidence for cannibalism is usually exactly this. It’s a bone that you wouldn’t bite in any sort of intra-specific combat. So with a T-Rex, when it leaves

speaker-0 (58:27.681)
yeah.

speaker-1 (58:45.07)
Tooth marks in another T-Rex’s skull, especially if they’re partially healed. It’s like, okay, well, they were fighting. They were biting each other on the head. If you’re scraping down to the bone on a foot, that’s not something that happens when you’re fighting. No. It’s like you can’t imagine two men fighting over a mate, a potential mate in modern society. Nobody’s chewing on the other person’s foot. They’re, you know, you’re they’re punching each other. Maybe you bit.

The person on like the head or something, if it’s getting really scrappy, but there’s no foot biting happening. That’s just not something that happens in an interspecific combat setting. And even if it was sort of predatory behavior, like you were saying, there’s not a lot of meat on the foot. So this is a last resort place to go for the meat. It’s probably not the thing that killed the animal that’s going to be chewing the meat off of the foot. Like you said, it’s probably a scavenger.

And that’s interesting to think that even something like a dyspletosaurus, which is a pretty large tyrannosaur, not compared to T Rex, but compared to most other theropods, might have been going after some of that easier meat. Yeah. And by easier meat, I mean it’s already yeah, it’s already dead. Not easy to get off the boat necessarily.

speaker-0 (01:00:04.138)
No one’s gonna fight back when it tries to get the last scraps. Yep. All right. Last up we’ve got a listener question. And it has been a while since we’ve done a listener question. If you have a question, you can go to inodino.com slash questions and we will eventually get to it.

speaker-1 (01:00:21.452)
Yeah, that’s a new link. We used to use bit.ly, but their whole situation got weird. So I know dino dot com slash questions is the new place if you wanna ask us a question.

speaker-0 (01:00:32.854)
Yes. So this listener’s question was I went to the Museum of the Rockies and there was a sign saying that T Rex was probably not a top predator like a lion, but more like a hyena, because they seem to be so common. Would this imply there’s a top predator that we have never found? And I thought this was very interesting because I’m pretty sure that both T Rex and hyenas are considered to be apex predators. A T Rex was obviously so big and had such a strong bite, could crush bone.

We know that because paleontologists have found pieces of bone in what could only be a tyrannosaurus turd. So it’s very likely an apex predator. It could hunt and also scavenge, because why pass up an easy meal? It could go after hadrosaurs, ceratopsians, and kyosaurs, possibly sauropods. We we just talked about all this. Also carcasses of marine reptiles and fish that washed up on shores. And there was a study in 2021 by Charles Marshall and others. We talked about this in episode 335, where they estimated about

20,000 adult Tyrannosaurus lived at any one time, although there’s a lot of uncertainties here. The median estimate was about 3,800 adult T Rex in an area the size of California and two adult T Rex in an area the size of Washington, D.C., so somewhat common.

speaker-1 (01:01:44.832)
Yeah, but that was the median. There were huge error bars on it. There could have been way more or there could have been a lot less. Yeah. Or fewer.

speaker-0 (01:01:53.494)
I’m just going with the median here to talk about that it’s kind of a common

speaker-1 (01:01:57.454)
Creditor. Yeah.

speaker-0 (01:01:59.202)
Kind of, yeah. It’s hard to say. But anyway, spotted hyena or laughing hyenas are generalist apex predators. They have strong bites. They can also crush bone. They can go after wildebeests, zebras, impalas, and more. They don’t really have a preference. They just want to eat. They’re social. They live in large communities of up to 80 individuals. Their group sizes vary and it depends on where they live and what the prey’s doing. Like there’s smaller clans where the prey migrates, and then there’s larger ones where the

speaker-1 (01:02:14.974)
Yeah.

speaker-0 (01:02:28.622)
Prey stays. Hyenas tend to forage in small groups. They don’t stick together all the time. Their territories can range from less than fifteen square miles to over three hundred and ninety square miles or forty square kilometers to over a thousand square kilometers.

speaker-1 (01:02:41.944)
That’s a lot of range. Yeah.

speaker-0 (01:02:44.396)
Now it’s hard to compare Tyrannosaurus and hyenas exactly because obviously they’ve got different body sizes, caloric needs are different, things of that nature.

speaker-1 (01:02:54.432)
Very different body proportions.

speaker-0 (01:02:56.834)
Yes. But with hyenas, hyenas are in the same niche and they compete with lions for food and lions often steal hyenas kills. Although hyenas steal food too, these from like cheetahs and leopards and wild dogs.

speaker-1 (01:03:10.318)
That is funny that it’s considered that hyenas are like scavengers in, you know, like the common understanding of hyenas. Meanwhile, lions are famous for being scavengers of hyenas prey, if anything, between the two of them. Yeah.

speaker-0 (01:03:27.918)
Well what I was thinking is maybe it’s more like there can be more than one apex predator. Although if you are talking about apex predators, that term just does makes it sound like there can’t be more than one. So it’s a little confusing.

speaker-1 (01:03:38.126)
Yeah, the apex. There’s only one apex, one tippy top. Yeah. But really it’s just about like trophic level. There’s a lot of animals where nothing eats them and a lot often there’s more than one in the same ecosystem.

speaker-0 (01:03:50.606)
Yeah. And so we see this with hyenas. Maybe the same went for Tyrannosaurus and we just don’t know what those other apex predators were yet.

speaker-1 (01:03:59.67)
Yeah. I think another thing that is really similar between hyenas and tyrannosaurs is that they both probably could eat bone. And that’s something that not a lot of animals do very often. But both hyenas and T Rex were fairly likely to swallow a a good amount of bone.

speaker-0 (01:04:18.882)
Yes. And then poop it out. Mm-hmm. Well, going back further in time to the Jurassic too, we’ve got the Morrison formation, you’ve got big carnivores like Allosaurus and Taurosaurus, which both were pretty much apex predators. Ceratosaurus didn’t do so poorly either, even though it was a little bit smaller. And they probably all hunted and scavenged and stole food. So yeah, with Tyrannosaurus it seems entirely possible. We we just don’t know what we don’t know. Although so far I don’t think there’s been evidence.

Of another apex predator in T Rex’s territory.

speaker-1 (01:04:52.034)
Yeah. I do think thinking of them like hyenas might make a little bit more sense because lions have a pretty complex social way of hunting, where a lot of times it’s the females as a group doing it and they’ll sort of herd an animal into a spot where another lion is waiting. We don’t have any evidence of T Rex doing that. And certainly the closest relatives we have today of birds and crocodilians don’t usually do that kind of thing. It’s more ambush.

speaker-0 (01:05:20.312)
Yeah, I don’t know if that works with comparing to hyenas because hyenas are social and live in big groups together.

speaker-1 (01:05:26.732)
Yeah, but I don’t know if they herd them into a spot to attack kind of thing. And I also don’t know how fast of animals they chase down. Although you did say they could take down an impala. Yeah that’s pretty quick. But I really think the reason this is there is because the Museum of the Rockies was Jack Horner’s spot and he was Mr. T Rex was a scavenger for a while. So there’s probably a little bit of that history which led to the hyena comparison.

in my guessing about it. Yeah. That could be a factor.

speaker-0 (01:05:59.65)
Hard to say.

So yeah, that wraps up our theropod segment. We will get into our, well, theropod dinosaur of the day in just a moment, but first we’re gonna take a quick break for our sponsors.

speaker-0 (01:06:45.782)
And now on to our dinosaur of the day. We’ve got a theropod to go with our theme of theropods. Mm-hmm. Ava Mimus, this was a request from Paleomike716 via our Discord slash Patreon, so thanks. We covered Ava Mimus in episode 170. That one’s titled Aurora Ceratops, but that was as a news item because it was about the newly named second species. So now it’s time to talk about the genus.

speaker-1 (01:07:12.144)
Ooh, both species.

speaker-0 (01:07:14.104)
Yes. Avimimus was an Ovaraptorosaurin theropod that lived in the Lake Cretaceous in what is now Mongolia. Ovarapterosaurs were the egg thief lizards, known for their short beaks and parrot-like skulls, but they actually probably brooded and took care of their eggs. Got misnamed. Avimimus was small and birdlike. It was about five feet or one and a half meters long. It walked on two legs. It had a tail, a short head, and a body covered in feathers.

Holotype had no tail, so originally it was thought to have no tail, but then more fossils were found later, which included caudal vertebrae or tailbones. So we know it did have a tail. It also had broad hips, and based on the broad hips, it may have had a long tail. We don’t know exactly how many tailbones it had, so mostly we know that it has a tail. It had long, slender legs with long shins compared to its thighs, and was probably a fast runner. It had three toes on each foot with claws and relatively short arms.

Its hand bones were fused together. It had feathers, but it probably couldn’t fly.

speaker-1 (01:08:14.348)
Yeah, short arms aren’t gonna help you with flight. Yeah.

speaker-0 (01:08:17.079)
No. But it did have a ridge on the lower arm bone or ulna, which may have been an attachment point for feathers, and it had quill knobs on the ulna.

speaker-1 (01:08:24.942)
That’s one of the craziest things about feathers to me, the ones that make it all the way down and to r attach directly to the bone with those quill doves. Yeah.

speaker-0 (01:08:33.431)
Now, Avomimus had a small skull, but large eyes and a big brain, and its skull bones gave extra support and protection to that brain. It had a beak and no teeth, but the holotype had tooth-like projections along the tip of the front of the jaw, the premaxilla. Later specimens found did have small premaxillary teeth, though. It may have been an herbivore or an omnivore, or an insectivore eating insects. It may have used its beak to crop plants. We really need to find gut contents to know what it ate. Mm-hmm.

Its backbones did not have openings for air sacs. Ovaraptorids and canignathids have them, so Avimimus may have been a more basal dinosaur. And Avimimus had a long, slender neck made of vertebrae that were longer compared to other ovoraptorosaurs. The type species is Avimimus portentosis, and that genus name means bird mimic. There is another dinosaur with a name that means bird mimic, that’s ornithimimus.

That means bird mimic in Greek. Avimimus means bird mimic in Latin. The first fossils of Avimimus were found in 1973, and then it was named in 1981 by Dr. Sergei Kurzinov. And in 1996, a second nearly complete skeleton was found that was described in 2000. Then a second species was named in 2018, Avimimus nemectensis. That one was named based on some subtle differences, such as bones with different openings, some wider spots, etc.

speaker-1 (01:09:35.948)
Uh-huh.

speaker-0 (01:10:00.908)
More than 500 dinosaur individuals have been found in a bone bed in the Nemet basin in Mongolia, and they include Avimimids, Canidnathids, and Ovaraptorids. All of them are closely related ovorapterosaurs. And that’s how they realized there was this second species of Avimimus. Both species of Avimimus are from the Nemet Formation. And Avimimus nemetensis is actually older than Avimimus portentosis, but

That doesn’t really matter when you’re naming a type species, it goes by what was named first, not which one lived first. Yep. There was a bone bed found in 2006 with thousands of bone shards. Fossil poachers had found the bone bed first, unfortunately. It was the first ovorapterosaur bone bed described, and it included at least 10 Ava Mimus individuals, adults and subadults, no juveniles. Most of that bone bed is Ava Mimus. There’s 160 or over 90% of the 177 documented specimens.

The rest of the fossils are from ovaraptorids, hadrosaurs, they have embryonic bones, birds, lizards, mammals, invertebrates, and wood. Hm. Now based on how the fossils were preserved, they were buried quickly, and then water flowed over the bones and moved them, and then they got buried again a short distance away.

speaker-1 (01:11:11.81)
That’s quite the puzzle figuring out which bones go to which animal, I’m sure.

speaker-0 (01:11:15.394)
Yes. And it’s unclear why the avamimus skeletons were together in the bone bed. It’s possible they were found together because they were gregarious or social. It could be they were flocking or lekking in an age segregated group with only mature avimimus, that would make sense. And for lekking, that’s when individuals come together to show off to potential mates. They likely died from a catastrophic mass death, although it’s unclear what killed them. There’s a high proportion of lower leg bones, which is unusual because there aren’t that many hip bones.

So it might mean that they were trapped in mud, but there’s no evidence of miring or mud because there was a second flow event, meaning the water flowed over the bones and moved them. So we lost a little bit of data there. But it’s the first evidence of gregariousness in Overactrosource. It’s possible that more dinosaurs than we previously thought were social, and then there was a trend to being more gregarious towards the end of the Mesozoic.

speaker-1 (01:12:06.028)
Yeah, that’s certainly been proposed for ceratopsians.

speaker-0 (01:12:09.502)
Mm-hmm. And kylosaurs, hadrosaurs, or nithyimids, and tyrannosaurs. The authors said that in the late Cretaceous, those groups show, quote, strong tendencies to form monodominant assemblages, regardless of how they were preserved or their environment preferences. So monodominant means like mostly one species. Now birds are gregarious, so it’s interesting to see these bird-like dinosaurs together. And it could help us understand the changes dinosaurs went through to become birds.

speaker-1 (01:12:29.186)
Gotcha.

speaker-0 (01:12:38.476)
Also in 2016, there was another bone bed described found in northern China, which included at least six individuals of avimimids. That bone bed was found back in 1959, which used bulldozers to excavate the site, and then there were more expeditions there in 1987 and 1988, but it didn’t get described until 2016. Sometimes things take a while. Some of the specimens may have been juveniles based on some of the bones beginning to fuse together, although according to the authors of that study, they were, quote, likely functionally analogous to adults.

They grew quickly based on histology or cutting into the bones. It’s possible that juveniles reached full size within a year. Avimimus lived in a semi-arid climate with wet summers and dry winters. Other dinosaurs that lived around the same time and place include hadrosaurs, pachycephalosaurs like Prinocephaly, sauropods, alvarosaurs like Mononychus, Drameosaurs like Aetosaurus, Ornithimimosaurs like dinachyris, canignathids like Elmasaurus, ovarapterids like Oxoco,

Therizenosaurs like Therizinosaurus, troodontids like Xanobazar, and tyrannosaurs like Tarbosaurs. There are, and then there’s other animals that were there too, like fish, amphibians, mammals, crocodilomorphs, turtles, and pterosaurs.

speaker-1 (01:13:43.659)
Famous dinosaurs.

speaker-1 (01:13:51.904)
One thing you mentioned about Ava Mimus that I hadn’t noticed in the skull reconstruction of it, I think when we looked at it years and years ago, were those little teeth like notches in the front of the beak. It they’re so interesting looking. It reminds me of some of the birds today that have bills that have like little teeth like serrations in them, but a little bit more intense and right there in the front. So I wonder what it was using those for. I don’t know. They make its skull look

Kind of intense.

speaker-0 (01:14:22.592)
Nice if we found some gut contents. Mm-hmm. And our fun fact, thanks for sticking with us, is that Tyrannosaurus tiptoed instead of stomped. This was published in Royal Society Open Science by Adrian Tusselboy and others. Now, previously, it had been thought that Tyrannosaurus walked heel first. It was flat footed and had a slow gait. Now it seems more like it moved like a bird, specifically like an ostrich. For this study, they looked at four specimens of Tyrannosaurus Rex.

based on them being fairly complete skeletons. So you’ve got Wankelrex, formerly MOR555. There’s also LACM twenty-three eight four five. Then we’ve got Sue and Stan. I’m not gonna bother with their numbers.

speaker-1 (01:15:08.226)
I think Wankel Rex is also the nation’s T Rex now, isn’t it? Yes.

speaker-0 (01:15:13.262)
So they measured the leg and foot bones, and they used three equations to estimate animal speeds. And they modeled three ways that the foot could hit the ground, if it landed on the heel, the middle of the foot, or on its tiptoes. And then they compared those models to humans and ostriches. And they chose to compare to humans and ostriches because they said they’re quote, the largest extant obligate bipeds, and differences in their gaits enable broader and more phylogenetically informed comparisons.

speaker-1 (01:15:39.34)
I never thought of us and ostriches as being lar the largest obligate bipeds.

speaker-0 (01:15:42.379)
yeah.

speaker-0 (01:15:46.419)
Largest animals that have to walk on two legs.

speaker-1 (01:15:48.926)
Yeah, it’s true though. You can’t go quadrupedal if you’re an ostrich because you’ve got wings. Yeah. And there’s no bird that’s bigger than them. And then in terms of mammals, the other big land animals, there aren’t that many bipedal ones. Yeah. I mean, like maybe something like a kangaroo would be close, but they hop and they sometimes use their tail in like a tripod. And they also sometimes use their hands a little bit, although we sometimes use our hands a little bit. But I suppose with kangaroos.

The hopping makes it not a great comparison.

speaker-0 (01:16:21.058)
Yeah, they probably use their feet differently. Mm-hmm. They also studied fossil footprints and saw the deepest marks under the toes. So that shows it had a tiptoe step instead of a heel first step. And the heel first step would mean low, heavy steps. But on tiptoes, it would take more steps in less time with its weight balanced over the toes. And that tiptoe style is like birds today. Humans, we run with relatively stiff spring-like steps.

T Rex moved in a crouched posture and took a lot of fast steps. So its legs acted like shock absorbers so it could stay balanced even on uneven terrain. They estimated that T-Rex moved 5 to 11 meters per second or 11 to 25 miles per hour, about 17 to 40 ish kilometers per hour. Ostriches can sprint at over 25 miles per hour, 40 kilometers per hour. And ostriches weigh between 140 to 320 pounds or

63 ish to 145 kilograms, which is significantly less than a tyrannosaurus. They estimated how fast individual specimens would have moved based on their weight, and they moved at noticeably different speeds. So Wankelrex is estimated to weigh six and a half metric tons and move about twenty-one miles per hour. That’s about thirty-four kilometers per hour. Sioux’s estimated to weigh about nine and a half metric tons and move at 14 miles per hour, 22 and a half kilometers per hour.

LACM23845 is a younger and smaller tyrannosaurus. It’s estimated to weigh 1.4 metric tons and move the fastest at about 25.5 miles per hour or 41 kilometers per hour. And then Stan is estimated to weigh 7.2 metric tons and move around 19 miles per hour or 30.5 kilometers per hour. So looking at their speeds, they probably preyed on different animals. This further supports that tyrannosaurus changed its diet as it grew up.

It had that ontagenetic niche separation.

speaker-1 (01:18:16.856)
That is kind of assuming that they had to chase down their prey to eat it. True. It’s possible they hunted in a way where their maximum speed was irrelevant. Yeah.

speaker-0 (01:18:25.358)
Yeah. And the authors acknowledged there’s limitations to this study and they said it is good to be used to inform future models. It’s more of a groundwork to compare more theropods. Yeah, we got a tiptoeing T Rex.

speaker-1 (01:18:37.378)
Yep. We’ve seen that before too, just in general with dinosaur locomotion, some of the studies of like how guinea hens walked and comparing that to the tracks of some of these larger theropods. And you see sort of this motion like you were talking about, where the toes hit first and then they sort of sweep through when it’s softer substrate, which is what you’d expect for a tiptoe versus a big heel impact, like when you see human prints in the sand or something. There’s like this big

Divot where our heel hits, kind of thing, and then the toes not as much. With dinosaurs, you have a totally different looking print. Yes.

speaker-0 (01:19:14.926)
Well that wraps up this Theropod episode of Ino Dino. We hope you enjoyed it. Thanks for listening. Stay tuned in our next Ino Dino episode, we will be talking about a new iguanodont with spikes. And we’ll also have an interview with artist Tara, who I don’t want to give too much away, but it has to do with our cool new upcoming dinosaur project. Mm-hmm. Which, if you’re a patron, you’ll have access to

Additional per

speaker-1 (01:19:46.124)
Yeah, there’s an exclusive level to the thing we’re announcing. Yes. You might have already seen some of it on our Patreon page. Yeah.

speaker-0 (01:19:54.408)
In the meantime, for our patrons, if you want more dinosaur content, we’ll have another dino download about soft tissues, an update to our soft tissues episode. And if you want to join so that you can access all this good stuff, head over to patreon.com slash iknowdino. Thanks again, and until next time.