It’s been a year since I started writing for the Gist, and over our lifetime we’ve amassed more than 200 posts. But the time has come to ride into the sunset – to kick off into that happy blogosphere in the sky, where the rivers babble with happy comments and the posts fly off the keyboards like tiny birds.

We’re retiring the Gist, and this is our goodbye post.

Over the last year, you’ve gallantly followed along as I posted about treebound evolution, extremely prompt pesticide resistance, first-hand penguin sightings in Antarctica, the crazy sanity of gas prices, the unimaginably huge turtle trade in China, giant prairie-stomping pterosaurs, a galactic collision that looks like Tinkerbell, very dead Norwegian (OK, Danish) parrots, NASA fashions, most possible angles on Tyrannosaurus rex and giant pandas, the oddly familiar numbing heat of Chinese soup – and, as they say, much, much more.

And I wasn’t alone. Virginia Hughes (who still blogs here) kept us updated on solar power, the Grand Canyon, and the suggestion that our time in history should be named after all the trouble we’ve caused. Sarah Zielinski tracked down a murder mystery involving gorillas and warned us about Burmese pythons invading the U.S. Laura Helmuth added news about dams and expensive gems.

But this is America, where everyone’s a sucker for a happy ending, even the Smithsonian. So the Gist isn’t totally vanishing: in its place you’ll find a sampler platter of new blogs: Dinosaur Tracking – hot and cold running dinosaurs; a new science blog called Surprising Science and written by Sarah; and my new project, with Laura Helmuth and Amanda Bensen: Food and Think, where we’ll be writing about the culture and science of food.

Food and Think had its beginnings this summer: a curious explanation for chile heat, and globalization’s role in reviving an ancient Oaxacan drink. We realized that food and cooking are marvelous, complex fields of study that also make our mouths water. Cuisine is the accumulated results of millions of amateur chemists in millions of kitchen laboratories. It’s chemistry distilled by history, and it’s completely fascinating. We hope to serve you some of the choicest tidbits – and to whet your imagination as well as your appetite. I can barely wait.

So thanks to everyone for reading, for commenting, for adding us to your RSS feed. I hope you’ll follow me over to Food and Think, or keep your eye on our other blogs if they suit your interest. I’ve had a great year snacking at the science news buffet; now here comes the main course.

(Image: Sunrise over South Texas, by Hugh Powell. That’s right – a sunrise. In every ending there’s a new dawn, after all. See you at Food and Think)

Ah, the last of the summer tomatoes. Plump, sun-warm, and soft. Sometimes I like to just eat them over the sink and let the rich purple juice run down my chin.

What’s that? You were expecting rich red juice? But purple could be so much healthier, according to this week’s Nature Biotechnology online. Scientists from England’s John Innes Centre succeeded in transferring two genes from snapdragons into tomatoes, boosting the fruits’ ability to produce pigments called anthocyanins. The resulting deeply purple fruit promoted longer lives when fed to laboratory mice.

This is one of those technological feats that makes you think “wow,” “ew,” and “the end of the world is nigh” all at once. I mean, I know this is done routinely nowadays, but just the thought that we know that somewhere inside a snapdragon is a gene that can persuade a tomato to change color is kind of amazing. Let alone that we can essentially cut and paste it into another plant without so much as a hiccup.

And it’s all because you haven’t been eating your vegetables. Fruits and veggies are high in a class of pigments called flavonoids that would be so good for you – if only you would eat them. But since only about 23 percent of Americans do eat enough veggies, Innes Centre scientists set out to invent a tomato with sky-high flavonoid levels. The idea being that instead of changing your eating habits, you can get healthy by squeezing ketchup over fries, eating pizza, and drinking bloody marys. Kind of neat thinking, really.

Enter the snapdragon: not popular on menus, but great at producing flavonoids. In particular, purple varieties called anthocyanins – the same stuff that makes blueberries blue and companies like Jamba Juice so eager to tell you about their smoothies. The list of health benefits the researchers provide includes

protection against certain cancers, cardiovascular disease and age-related degenerative diseases. There is evidence that anthocyanins also have anti-inflammatory activity, promote visual acuity, and hinder obesity and diabetes.

Sounds good, but I’m still not convinced purple tomatoes are the best way to get my anthocyanins. I’m not a raving opponent of transgenic crops (though I disagree with patenting them). I just think I’d rather have blueberries on my cereal than eat purple spaghetti. Heck, I’d probably rather have blueberry spaghetti.

(Image: John Innes Centre)

Fad dieters take note: The Innes Centre website takes care to point out in bold type that seeds are not available for sale.

Men are under natural selection to become richer, according to a report in the November issue of American Naturalist. That’s right: the same way natural selection once encouraged longer necks in giraffes and duck bills on ducks (and platypuses), men are now feeling that Darwinian pull toward the corner office.

The Newcastle University researchers found the effect only in men, and explained it by saying that

men strive for cultural goals such as wealth and status in order to convert these achievements into reproductive success.

Women showed the opposite effect: lower incomes were associated with more children (the researchers interpreted this as women giving up earning potential in order to have kids). All sorts of other interesting societal lessons cropped up in the study. The effect held across typical Western societies (the U.K., Sweden), in African hunter-gatherer societies, and in family records of Europeans spanning the last 500 years.

This research is kind of a brutal reminder that civilization doesn’t trump evolution, it just shifts the focus. Quasi-philosophical discussions about whether we’ve stopped evolving are fun, but there’s really only one right answer: Of course we’re still evolving.

Evolution is just the slow genetic shifting of the norms in a population. It happens to the best of species – even ones that have invented flu shots, indoor plumbing, and airbags. Case in point: I have terrible eyesight, but thanks to contact lenses I’ve avoided being eaten by wolves or walking off cliffs. So you might argue that our superb mammalian eyeballs have stopped evolving.

But I’m still childless. If I keel over tomorrow then, evolutionarily, I’ll have vanished.**** My genes will sink into the dirt along with the rest of the contents of my cells. Which of my genetic traits will be to blame? My enormous Anglo-Saxon cranium? The tendency to recite Monty Python on first dates? Too busy blogging to meet real people? Or my paltry earning power?

The point is that natural selection is at work, blindly weeding out genes, even if in less blood-curdling fashion than we often think of it. Of course, selection is only one of evolution’s three ingredients. To actually evolve, a population needs to be variable, different individuals must have differential reproductive success (that’s selection), and they must be able to pass those differences on to their offspring (that’s heritability). But all those are met, the researchers argue: just ask the Kennedys.

Presumably we’re not evolving some kind of Susan B. Anthony-producing sweat gland, of course. But more subtle abilities (or predispositions) to accumulate wealth are being rewarded with more children. And although evolution takes a long time, the results from this study suggest this selective pressure is as old as the barter system. I wonder what exaggerated features it has already produced, giraffe- or peacock-like, in our bodies and our psyches?

(Image: courtesy Matt Schwartz. disclaimer: enormous cranium notwithstanding, that’s not me in the picture)

***Except for whatever I have in common with my nephews and nieces.

The science news last week was peppered with common-sense breakthroughs: among them, an elephant-rampage early-warning system and a hospital centrifuge made from a hand-cranked eggbeater.

It’s a good time for modest ingenuity to make a comeback, since our plummeting economic fortunes are dampening enthusiasm for, say, an $8 billion physics project that keeps getting the hiccups – or even a $450 million Mars landing that goes off flawlessly. So clip the following coupons to get great science at discount prices:

Hand-powered blood sample prep: Transporting a delicate medical centrifuge to a remote village to fight infectious disease is tricky enough, not to mention the problem of finding an electrical outlet once you get there. Sure, you could carry in your own generator and diesel fuel, or you could collect blood samples, put them on ice, and ship them to the nearest hospital. But a team of Harvard researchers thought up a much more satisfying option (I like to think it was over an omelette breakfast). Start with a $2 hand-powered eggbeater. Remove one of the beaters and tape your blood sample to the other one. Crank. Even untrained helpers can hit 1,200 rpm, the team reported in the journal Lab on a Chip - plenty to separate blood cells from the plasma doctors need for running diagnostic tests.

Elephants own up to mischief by text message: In some parts of Africa elephants are still being mercilessly poached for their ivory, but elsewhere they raid fields, destroying crops and engendering ill will. Twenty-four-hour elephant surveillance, a la the black helicopters in Goodfellas, is hardly an option. Instead, rangers attach radio-collars to troublemaker elephants. When a geolocator in the radio-collar realizes the elephant is headed for a farm field, it text messages the rangers so they can warn it away.

(A somewhat similar text-messaging method detects whale calls in Boston’s shipping lanes and alerts officials to the danger of a collision.)

And finally, we learn that worms hate the sound of moles. They come writhing out of the ground by the spaghetti-load at a mole’s merest murmur – or the reasonable approximations performed by “worm-grunters.” (OK, so this breakthrough isn’t as practical as the eggbeater centrifuge. It’s a great piece of experimental science – and who knows what it could do for the bait-worm economy?)

Wired Science noted the story first, and pointed out that Charles Darwin himself had thought through the problem in his exhaustive tome on earthworms. He proposed moles as the cause – but it took another 120 years or so for someone to put together the proper experiment.

The thing I love about “common sense” breakthroughs is that they’re only common sense after somebody thinks of them. Until then, we just have pieces of a solution arrayed in front of us, hiding in plain sight. Makes me wonder what kind of discoveries are in my own kitchen. And where I can get some of that ingenuity.

(Image: Wikipedia)

Barring an observation or two about how science is or isn’t cropping up in this campaign, the Gist is not a political blog. But as someone who still remembers sixth-grade planetarium visits where I craned my neck against the theater seats to watch the stars wheel by, I do feel a responsibility to speak up about a recent instance of planetarium-bashing.

I’m not talking about John McCain’s portrayal in the second debate of a state-of-the-art sky projector as a foolishly overpriced $3 million overhead projector. That mischaracterization was pointed out nearly instantaneously by the Chicago Tribune, Washington Post, Sky and Telescope, Wired Science, Bad Astronomy, Cosmic Variance, Boing Boing, and Gizmodo, among others.

What prompts me to post about it now is McCain’s decision to repeat the mischaracterization in the third presidential debate, last night. McCain’s aversion to pork barrels and earmarks is laudable, and with so many of them floating around in the federal budget, I just don’t understand his determination to dump on the defenseless and lovable planetariums of the world.

As a visit to your local planetarium will affirm (try the Smithsonian’s Einstein Planetarium if you’re in D.C.), that lens-studded spherical contraption that faithfully projects the night sky onto the ceiling is a far cry from the overhead projector your 11th-grade history teacher chronicled the Reconstruction on with smelly blue markers.

Granted, for $28 you can order a home planetarium complete with nine revolving planets that runs on AA batteries – but something tells me the light bulb on it is not quite up to snuff. A few thousand more can get you an ingenious inflatable planetarium, but it maxes out with considerably less than a school-bus-full of kids.

To run a world-class planetarium that brings the mysteries of space to millions of visitors, day in and decade out – as at Chicago’s 78-year-old Adler Planetarium, I think that going with a name brand qualifies as money well spent.

Now, if we can just leave the science educators out of the earmark wars, perhaps we can concentrate on what the candidates say about the other $699,997,000,000 that has the country so worried?

(Image: Google Earth/NASA; it’s a patch of sky directly above the Gist and dead in the center of the constellation Leo. It is mesmerizing to zoom deeper and deeper into space in this program – the stars just keep on coming. You should try it in a planetarium.)

A bit of household science in the New York Times this week has wrecked my decades-old reverence for the cast-iron skillet. That’s according to data from the kitchen of Harold McGee, the great foodie-chemist and author of On Food and Cooking – a book that’s nearly as important to your kitchen as a decent chef’s knife.

McGee decided to settle a question that I thought I knew the answer to: In pans, what material handles heat best? He tested five skillets ranging in price from trusty $25 cast iron, through various mid-range varieties of aluminum, on up to a steel-coated copper pan that topped $400.

Now, I’ve always felt a kind of earthy piety when cooking with my trusty cast-iron skillet, which is going on 15 years old. Whether it’s delicately crisping a grilled cheese or setting off the smoke detectors over blackened salmon, I’ve always congratulated myself for sticking with its old-fashioned, even-heating perfection in the face of modern nonstickiness, metallurgical trickery, and charming pastel enamels.

So imagine my surprise. McGee’s “point and shoot” thermometer (forget new pans, I want one of those) indicated the cast iron pan was 100 degrees cooler at its edges than in the center. Pretty much every other pan design heated more evenly (and most more quickly) than cast iron. At first I didn’t want to believe, but the accompanying photos of toasted parchment were devastating.

Along the way, McGee discovered why butter does a better job than oil at keeping food from sticking, and turned up a principle called Bénard-Margoni convection to explain the ripples that appear in hot oil and look like the “legs” in wine running down a glass.

Three of McGee’s skillets had nonstick coatings – something I’ve sworn off. They’re a Catch-22 of annoyances: First, food always sticks to nonstick coatings. And second, you have to spend the rest of the evening waving a limp plastic scrubby at the problem for fear of further damaging the coating that doesn’t work in the first place. (Sure enough, McGee saw nicks appear in the nonstick armor of two pans during his experiments.)

Which leaves my only remaining point of pride with cast iron: When you do hopelessly burn a quesadilla, frittata, or korma into the bottom of your pan, you can at least attack it with steel wool and elbow grease.

(Image: H. Powell)

The 2008 electoral campaign has now brought us three debates. After 270 minutes of argument, the word “science” or “scientists” has been used approximately four times.

That would be three times in the first presidential debate*** (transcript), zero times in the vice-presidential standoff, despite the candidates being asked point-blank their views on climate change and its causes (transcript), and approximately once in the second debate.****

Perhaps we’ve reached the point where science is so ingrained in our culture that we don’t need to say its name. All four candidates spent plenty of time on economics and energy independence – two areas in which science and its city cousin, technology, are the bedrock of the discussion.

But then, if we don’t ever talk about science, how do we maintain or regain our country’s focus on scientific literacy, and train new experts in science’s ever-shifting frontiers? The words “education,” “teachers,” and “students” have been almost as rare in debate transcripts as science.

At least we can thank the National Science Foundation and Science magazine for encouraging people to think of new ways to imagine it. Their six-year-old Visualization Challenge rewards scientists and science outreach for finding compelling images and videos to get people to pay attention to research. The 2008 winners were announced at the end of September.

Above, the winner in photography is an electron micrograph of katydid-colored diatoms clinging to a hair-sized invertebrate in the Mediterranean Sea. Diatoms like these may produce as much as 40 percent of the world’s oxygen.

Points for whimsy go to a beetle’s tea party depicted in “Alice’s Adventures in Microscopic Wonderland,” the winner in Informational Graphics. Other memorable images show word linkages in the Bible and Op-art results of an experiment in polymer science.

I particularly loved the attempt by some German computer scientists to describe the shortcomings of current virus protection software and propose a next-generation solution. The team won an honorable mention in Non-Interactive Media for their cartoon short “Smarter than the Worm.” It’s charming to watch and so simply explained that you’re almost fooled into thinking you knew this material already. But you probably didn’t.

Here’s the vaguely Where the Wild Things Are-ish YouTube video, in English, for Smarter than the Worm. Watch it… then consider telling your politicians you’re ready for a renewed emphasis on science research and education.

Previous years’ Visualization Challenge winners are here.

(Image: NSF/Mario de Stefano/Second University of Naples)

***For the record, all three times by Barack Obama.

****This was when Obama noted that scientists were present at the start of the computing industry and implied we would need them again as we reshape the energy industry.

A new dinosaur discovered in Argentina had labyrinthine lungs that extended into hollows in its ribs, hips, backbone, and wishbone. It’s a rudimentary version of the lung system found in birds, where it allows breathing to be far more efficient than in mammals.

The dinosaur, named Aerosteon riocoloradensis this week in the open-access journal PLoS One, was a 30-foot long predator that raced about on two legs, though it lived some 17 million years earlier than Tyrannosaurus.

Disclaimer: Now, we at the Gist do realize that the Mesozoic world contained more than just rapacious bipedal predators. And we are looking forward to writing about, say, a peaceful, heavily armored, cycad-munching Ankylosaurus one of these days. We just can’t help it that these newsworthy lung pockets happened to be found in the bones of a large, scary meateater.)

In fact, the new-fangled lungs and the body they came from might not be a coincidence at all. Air sacs nestled in the bones of birds help them route air through their lungs in a one-way circuit, so that nearly all the air is exchanged with each breath. By contrast, our own system of sucking air into the front of our lungs, then pushing it back out again, leaves lots of old, stale air in our lungs on any given breath.

For birds, their bellows-like breathing system is the equivalent of those blowers that stick out of the hoods of 1970s muscle cars: it’s a ready supply of fresh oxygen they can use to supercharge their engines. That’s one reason why birds can fly so explosively. And if Aerosteon‘s lung structure gave it the same sort of ability, it might make sense that the system evolved in an animal that has to run down prey for a living.

Of course, scientists are always wary of a good argument without good evidence – that’s what they call an evolutionary Just-So Story. So lead author Paul Sereno and colleagues suggested a couple of alternative advantages that might have led to the appearance of Aerosteon‘s aerated bones (which, by the way, is what “aerosteon” means).

Shifting the lungs lower in the torso, they suggested, would lower the beast’s center of gravity and place it over the legs, perhaps making it a better runner. Another possibility is that pushing more air across moist lung surfaces helped with evaporative cooling. Overheating can be a severe problem for large animals that live vigorous lives in warm climates, since heat has a harder time getting out of a large body than a small one.

Now, does anybody have any tips on late-breaking Ankylosaurus research?

(Image: Todd Marshall/Project Exploration)

The Gist has been on a field trip in New York City this week, taking culinary detours into Italy, Korea, Lebanon, Ireland and the Sichuan province of China.

The Grand Sichuan International in Chinatown is a living-room-sized restaurant with an invisible kitchen, a dozen tables, and a soft-drink cooler wedged against one wall. Grand or not, it’s where I learned the meaning of ma la, the Chinese name for a soup made of dried chilies and Sichuan pepper. It arrived as a steaming tureen, set before us on a portable gas burner and filled with a bright-red bubbling liquid. Crispy dried chilies – perhaps 40 of them – bobbed in the waves like radioactive minnows, and we eventually fished them out to keep the soup from getting any hotter.

But the real draw were the small woody flecks of Sichuan pepper floating in the broth. At first, these gave the soup a random and alarming crunchiness. But moments later the taste developed into a citrusy buzzing and tingling over my mouth and tongue. As it went on, the feeling almost perfectly balanced the heat from the chilies, mellowing it and sweetening it in waves that sloshed across my mouth. That’s ma la: “numbing hot.”

The nearest equivalent is the tingling you get from eating orange or lemon zest (or perhaps, the weird taste/sense as your tongue comes back to life at the dentist’s). But for me, the sensation brought back precisely a visit to a south Georgia barrier island some 15 years ago. I had searched the back dunes for a tree in the genus Zanthoxylum. Sometimes called “toothache tree,” the leaves are supposed to make your mouth go numb. When I found it, it was a short, stout tree covered with immense thorns and sporting leathery dark-green leaves. At the time I was disappointed that my mouth didn’t go completely numb, but the sensation was identical to the lemony fizz of my Sichuan hot pot.

Back home, a little reading turned up why. Sichuan peppercorns (or huajiao) are the dried seed husks of a few Asian species of Zanthoxylum (one of many neat botanical holdovers from the days before the Atlantic Ocean stood between Eurasia and North America).

Fortunately for us, ma la and Sichuan pepper have not escaped the notice of chemists, and a 1999 paper in Brain Research suggests why the spice can make our tongues feel so many things at once. The lemony taste and tingling sensations come from a half-dozen volatile oils, the most peculiar being something called hydroxy-alpha-sanshool. When scientists tested this compound (on rats), they found it activated several different classes of neurons, including touch-sensitive, cool-sensitive, and cold-sensitive receptors.

Sichuan pepper is in the citrus family and is unrelated to white, black, or red peppers. Importing the spice to the U.S. only became legal in 2005 after fears eased about its potential for transporting a citrus disease. So, if I arm myself with some Zanthoxylum berries and the right cookbook, might I be able to recreate my hot pot – and make my taste buds do back flips again? After my nose stops running, I’m going to try.

(Image: the toothache tree of North America, Zanthoxylum clava-herculis; amyb/Flickr)

Behold the fearsome Manospondylus: one of the largest, fiercest predators the world has ever seen. With a skull the size of a wrecking ball and teeth like scimitars it terrorized the Cretaceous fens, eviscerating plump vegetarians and kicking around the skinny ones like discarded soda cans.

What’s that you say? Sounds an awful lot like a T. rex? That’s because Manospondylus was T. rex’s original name – coined in 1892 before the monster acquired its rather more striking name (in 1905) and started getting into showbusiness.

The mixup is an example of a very basic problem in paleontology: How many species of dinosaurs were there, and how do we know we haven’t named something twice? Scientists have named about 1,400 dinosaur species, but slightly fewer than half of those actually merited their classification upon closer inspection. Fortunately, a new study by British paleontologist Michael Benton suggests that we’re getting better at catching these mistakes.***

According to the study, the modern rate of discovering new dinosaur species is a breakneck 30 species per year, about double the previous peak of dinosaur-naming, in the so-called “Bone Wars” of the late nineteenth century. But because paleontologists have discovered very high quality fossil beds – especially in North America and Asia – they’re now working with much more complete material.

If you’ve ever had trouble figuring out how many kinds of ducks you’re feeding at your local city park, you might relate to the problem paleontologists face. They’re usually trying to differentiate species based on characteristic bumps, fissures, and cavities they find on whichever bones someone has managed to dig up.

Imagine trying to tell a mallard from a pintail based only on the shape of its kneecap, and you get an idea what they’re up against. Manospondylus was named from two large but shattered vertebrae, while the first Tyrannosaurus was named, 13 years later, from a partial skeleton. It wasn’t until 1917 that the similarity between the vertebrae in the two separate finds was recognized.

As a result of the recent flurry of advances, Benton reports, we may be honing in on a guess of how many dinosaur species there really were. At the start of the nineties we guessed there might be 1,200 species, but after a decade of discoveries and some 300 new species, that figure has risen to perhaps 2,200. With only about 675 “valid” species on the books right now, that leaves some 1,500 entirely unknown dinosaur species to discover. Ladies and gentlemen, grab your rock hammers.****

(Image: Wikipedia/David Monniaux)

***Kind of incredibly, Benton suggests that whatever naming mistakes might be happening nowadays are partly the fault of – you guessed it – the media. From the paper:

The aims of this study are to explore the recent burst of dinosaur work and to resolve whether the new phase is illusory or not. It could be that palaeontologists are producing poor-quality work, perhaps fuelled in part by excessive interest from museums and the media worldwide

****We also recommend obtaining a Ph.D. in paleontology.

Here at the Gist we try to keep you on top of breaking science of all kinds. Sure, you get popular hits like massively expensive particle accelerators and nail-biting Mars touchdowns. But we reach deep into the heart of science, too, bringing you topics like top-quality dingo urine and paranoid squirrels.

This week we learned that dogs can catch yawns from people. And the evidence on this one is pretty solid. It comes from a controlled experiment conducted on 29 dogs of different breeds and posted this week in Biology Letters, the top-flight journal of the Royal Society of London.***

A stranger sat in a room with each dog for five minutes and either (a) started yawning (with sound effects) or (b) simply opened his mouth wide, but without moaning or even scrunching up his eyes. (The authors include a great photo-sequence of the two facial maneuvers [subscription required].)

The results came out clearer than a Higgs boson in a 17-mile Swiss tunnel. Not a single dog yawned when confronted with a simple open-and-close of the mouth. But on average, after watching just a minute and a half of real yawning (equal to about 4.5 yawns), the dogs opened wide. Only a few were totally immune to yawns, including a weimaraner, a shih tzu, a Jack Russell-corgi mix, and a great dane.

One dachsund resisted yawning, but he was offset by three others that yawned with aplomb. Prolific yawners included a lab and a Staffordshire bull terrier, with four yawns each. But the champion yawner? Big surprise: a border collie, the smartest dog in the world. He probably also had an opinion on which statistical analysis to use.

Here at the unofficial Gist Center for Animal Psychology we attempted to replicate the experiment on a Rhodesian ridgeback mutt (above). He took considerably longer than 1.5 minutes to start yawning, and then only because one experimenter was scratching him behind the ears, which he really likes.

(Image: Tupelo finally yawns; Charles Eldermire)

***In the world of animal cognition, this actually is pretty neat research. Lots of animals yawn, but the only animals known to pass yawns from one to another are humans and chimpanzees. This finding suggests dogs really do empathize with humans to some extent – and in any case it says something pretty neat about the ways domestication has caused our evolutionary histories to become intertwined.

Turn the clock back 230 million years, and the land was covered with big, toothy reptiles.***  But as many a nine-year-old can tell you, not all of them were dinosaurs. Some were “crurotarsans,” a lineage that all but died out just as the dinosaurs were acheiving global domination. Today, the only crurotarsans are the crocodiles. But alas! It all could have been so different, according to research published in Science today by Stephen Brusatte, of Columbia University, and colleagues.

The Age of Dinosaurs may have been a matter of luck, they say: just a matter of which group was hit harder by a mass extinction 200 million years ago. Before then, for nearly 30 million years, dinosaurs and crurotarsans had vied for superiority in a classic Darwinian struggle.

And the crurotarsans should have won, the scientists argue. After analyzing the fossils of 64 species, they found the beasts had a greater variety of body plans – and evolved new species at about the same rate – as dinosaurs. They take this as evidence that dinosaurs weren’t innately superior creatures (otherwise, the reasoning goes, more dinosaur species would have evolved as they usurped the crurotarsans). In the race for supremacy, it wasn’t that the dinosaurs outpaced the crurotarsans – it’s more like the crurotarsans were felled in the home stretch by a calamity.

But hang on a second. I’m all for exciting new theories that offer explanations no one’s thought of before (i.e., prairie-stalking pterosaurs). But this logic sounds wonky in a few places. Does a lack of species divergence have to mean an ecological stalemate was going on? Or could it mean that the species in existence at that time were doing phenomenally well on their own? For that matter, might the rapid appearance of new species signal a sputtering lineage, dying out in a flash of ill-fated new forms?

More problematically, how does a mass extinction kill nearly all the members of one group (crurotarsans) without destroying a similar number of the other (dinosaurs)? That doesn’t sound like the luck of the draw; it sounds like one of those groups had a competitive advantage – what the regular person might call “superiority.”

Full disclosure: I’m not a paleontologist. Perhaps these are well-thought-through ideas that the authors lacked the room to explain in their paper. (If so, I’d love it if a real paleontologist would write in and educate me.) Maybe the authors imagine that a different kind of mass extinction (meteoric fireball vs. global warming, for instance) could easily have switched the tables and led to an Age of Crurotarsans.

But then, the crocodiles did survive, apparently content to hide out in the swamps for 200 million years while the dinosaurs enjoyed their 135 million years of fame – and then died out. Come to think of it, maybe the crurotarsans are superior after all.

(Image: the crocodile, last of the crurotarsans, Wikipedia)

***To be fair, there were also plenty of small and medium sized reptiles, some with rather ordinary teeth.

After 26 years of listening for radio transmissions from deep space, we learn this week that aliens – at least the really smart ones – could have been trying to contact us by a totally different method: manipulating the brightness of stars using stupendously powerful blasts of neutrinos. Or so say University of Hawaii physicist John Learned and his colleagues in a recent article on the physics forum arXiv.

It’s simple, writes Learned: aim your neutrino beam at a pulsating Cepheid star, and with enough energy input you can change the frequency of the pulsations – a kind of binary signal that any old sentient being equipped with eyes and a modicum of curiosity could pick up on. I mean (and you can almost hear the exasperation in his words), even humans have been watching Cepheids since the late sixteenth century.

Learned calls the technique “star tickling” and suggests that star-tickling aliens could even now be waiting for us to clue in and start deciphering the oscillations. He suggests that data could be transferred over immense distances this way, giving us a sort of “galactic internet.” You’ve got to give him credit for thinking big.

Still, you wouldn’t want to swap too many vacation photos on this system. With data rates of roughly 180 bits per year, according to Nature News, that 100 kB picture of you eating a fried twinkie at the fair would take a bit more than 4,500 years to download.

So it’s really more of a galactic telegram system. Also, you could run into trouble on your power bill. Each neutrino blast needs to contain roughly 1 millionth of the star’s energy before the Cepheid starts feeling ticklish.

But I like this expansive thinking. Whenever I get to talk with physicists, I always come away thinking how marvelous it must be to spend so much of your life being mostly correct and nearly insane all at the same time. And if you’re going to spend your time thinking of ways that aliens could be calling to us, you might as well cover all the possibilities.

Best of all, Learned keeps his suggestions practical, stopping well short of the ludicrous:

“In another context, the use of the cosmic microwave background to reach everyone in the universe was also considered [5] but as far as we know that is not within the capability of any inhabitants of the universe.”

At least with Cepheid stars, we have 100 years of observations to fall back on. A graduate student given a laptop and enough Code Red could have the answer in a few months. (Although, their optimism notwithstanding, it does appear that Learned and colleagues opted to publish their paper before running that analysis.)

(Image: the Large Magellanic Cloud, NASA; from Hubble Science Year in Review 2006), featuring advice on how to calibrate Cepheid stars)

It’s not quite astrobiology rap, but a YouTube plea for finding common ground between science and religion is notable for its source, the American Association for the Advancement of Science, the country’s leading association of scientists.

The video is a trailer of sorts for a longer film available from AAAS. It features two prominent scientists – Science publisher Alan Leshner and Human Genome Project leader Francis Collins – plus two high school teachers, all describing the equally prominent roles that science and Christianity play in their lives.

Collins says it best: “It would probably be a good thing if scientists like myself who are believers would explain why, from our perspective, we find no difficulty putting these two views together, and also why intelligent design was not the way to do it.”

The video is a response to a much-talked-about documentary called Expelled: No Intelligence Allowed, released earlier this year. The movie makes anti-evolution arguments and gets hopping mad about the treatment (or indifference) intelligent design has received from scientists. The scientists themselves – some of whom appear on camera – are hopping mad to find their words have been cherry-picked to fit what they regard as an unflinchingly creationist movie.

With all the inflammatory rhetoric circulating around both sides of the movie – and around much of the intelligent design controversy – it’s refreshing to hear Collins’s gentle summation:

“It’s time to put the battles to rest, abandon the battlements,” he says. “Let’s get back to the middle ground that people have almost forgotten is there, and celebrate science, and celebrate faith.”

As the election season heats up and we find ourselves once again being neatly categorized, red-vs-blue fashion, by pundits and headlines, it’s worth remembering that it’s not even that complicated. Aren’t we just one nation, under God (or perhaps the Flying Spaghetti Monster)? Free to believe, to question, to argue, and ultimately to agree to go on living together?

(Image: Michelangelo, The Creation of Adam [1511]; hat tip: Panda’s Thumb)

So I’m catching up on my Current Anthropology, and suddenly I’m craving something I never knew existed: tejate, a cold, frothy, corn-and-chocolate drink from Oaxaca, Mexico.

Put it down to a recent brush with a silky, nutty Oaxacan black mole sauce, but suddenly I am really interested in chocolatey Mexican cuisine. I’m also curious because dark tejate sounds like the mysterious twin of horchata, a milky rice-and-cinnamon drink that is my current favorite Mexican refresher.

But tejate may also tell us a story of both caution and hope for globalization, say researchers from the University of California, Santa Barbara. They take issue with the popular notion that global commerce is destined to blend the world’s cuisines into some kind of bologna sandwich of a common denominator. In one of the best opening salvos I’ve seen in a scientific paper, the first line reads:

Leaving out massive fragments of the past to discuss globalization as a unique contemporary event is not only shortsighted but often ethnocentric and limits our understanding….

After all, they point out, Oaxacans in open-air markets were selling something very like tejate when the conquistadors arrived. Globalization may be accelerating, they say, but don’t pretend that trade routes are something new.

Daniela Soleri and her coauthors have staked out a position that isn’t easy to defend. Industrial agriculture has put many small U.S. farmers out of business and replaced the heavenly squishiness of peaches and tomatoes with something more suited to firing out of a cannon. And with the advent of the North American Free Trade Agreement, our prodigious ability to grow corn has flooded Mexican markets with cheap, generic cobs, to the detriment of local varieties that are centuries old.

And in surveys of two Oaxacan villages the researchers did find that more contact with “the outside world” – as measured by literacy rates and proportion of people speaking Spanish versus the local Indian dialect – translated to less tejate consumption, less home-made tejate, and fewer local ingredients used in the brew. Tejate isn’t easy to make (the article includes a recipe), requiring not only corn and cacao but other local ingredients with names like pixtle and cacahoaxochitl, as well as wood ashes.

But here’s the twist: globalization works both ways, invading the villages at the same time it chases local secrets out into the world. As mass-produced corn barges into Mexican neighborhoods, wistful immigrants in Oaxaca city and even Los Angeles create a far-flung demand for the lesser-known varieties. Tejate may be experiencing a downturn in its homeland, but suddenly there’s a market for it in L.A. The researchers found a thriving home-brewed tejate business there that uses pixtle mailed from Oaxaca, maize from a pet-food store, and ashes collected from a local barbecue restaurant.

You can see this agricultural diaspora for yourself at nearly any farmers market: all those Peruvian and Russian fingerling potato varieties, lemon cucumbers and striped beets – all the way to rare triumphs like wasabi root and the infamous durian. (Going a bit farther, the New Yorker recently expounded on a few cherished varieties of medical marijuana.) A pizza restaurant near my home sells handmade El Salvadoran tamales, advertised on a handwritten sheet of spiral-notebook paper taped above the cash register.

As a half-Southern, half-English military brat, I say “Bienvenidos!” My culinary inheritance centers around fried chicken and Marmite sandwiches, and I’m grateful every time I find a good pasilla pepper. I can’t wait till tejate arrives.

I just wonder what it tastes like.

(Image: an Aztec figurine holds a cacao pod; Wikipedia)