The “blue jeans” color morph of the strawberry poison dart frog, Oophaga pumilio, from Costa Rica.
Image from Wikimedia Commons user Pstevendactylus

Mate choice is one of the most well-studied aspects of evolution. To prove that they’re worth the effort, animals will do just about anything. They dance, prance, sing, bellow, and fight for attention. When you look around the animal kingdom, the wild results of mate choice boldly stand out, from the impractically beautiful tails of peacocks to the ostentatious antlers of elk and deer. With so much focus placed on quality, you might assume that every species has their own complex way of conveying their worth, and that all of the females of the world are finicky creatures.

But not so for the female strawberry poison dart frog — when she’s ready to mate, she doesn’t pick the strongest or the brightest guy around. She just goes for the closest.

This came as a shock to Ivonne Meuche and her colleagues from the University of Veterinary Medicine in Hannover, Germany. Strawberry poison dart frogs are some of the most colorful animals on the planet. There are more than a dozen color morphs, from the bright red they’re named for to vibrant blues and greens. When the mating season arrives, male frogs gather in these large groups called leks to vie for female attention. In other lekking species, these large displays sort the men from the boys in the minds of the females, with the most impressive singers/dancers/etc winning the most matings. It is believed that these large groups give the males a chance to prove their top-notch genes or parenting skills. So the scientists wanted to know what drives mate choice in these colorful frogs. Does their bold coloration play a role? Or, like in other species of frogs and toads, does size matter most?

Listen to a male call:

To test female choice, the team played male calls that varied in pitch and rate made by frogs of different sizes and shapes, and watched to see which the females picked. The female frogs didn’t choose based on any of those factors, though. “We did not find female preferences for certain call properties or physical properties,” the authors explain. “Our data suggest that in our study population, female strawberry poison frogs use a mate sampling tactic that could be defined as “accept the closest calling male”.” When it comes to convincing a female strawberry poison dart frog, a male doesn’t have to be the strongest or the handsomest. He just has to be the first she gets to.

The scientists believe this very non-choosy behavior is a result of the reproductive biology of these colorful little frogs. They found that when a female is ready to lay eggs, she has a short time frame in which to do so. Females that don’t mate in that window end up laying unfertilized eggs, thus squandering their body’s efforts to reproduce. Since time is of the essence, the best choice available for these girls is to take what they can get, for even a lesser quality mate is better than no mate at all.

“Strawberry” is a misnomer: an example of the stunning diversity of color in these little frogs.
Image courtesy of Wikimedia Commons user Dendrotoine85

The authors do note that their study has limitations. Populations of strawberry poison dart frogs vary a lot in the natural world in many ways that the team was unable to test. For example, the proportion of males to females or potential egg-laying sites might shift how females behave. Other studies have found that when there are more females than males, as was true in this study, that the pressure to be picky relaxes. So, further research, in the lab and in the wild, are needed to determine if this species has multiple tactics for choosing mates, or if the closest male always wins out.

But, at least in their study population, the team is confident in their results. And it makes sense — the cost of searching for a better mate is high for these bright little females, so it’s not worth their time to be picky. “High egg mortality as well as the risk of losing the whole clutch by laying unfertilised eggs and the probably low benefits of intensive mate sampling support our assumption that acceptance of the closest calling male represents an optimal mate sampling tactic in female strawberry poison frogs,” they write. The longer these frogs wait to mate, the more likely they are to fail altogether. So why not just pick any guy and hope for the best?

 
Citation: Meuche I., Brusa O., Linsenmair K.E., Keller A. & Pröhl H. (2013). Only distance matters — non-choosy females in a poison frog population, Frontiers in Zoology, 10 (1) 29. DOI: 10.1186/1742-9994-10-29

Plus, bonus footage of grizzlies catching fish!

An Anopheles gambiae mosquito gorging herself on blood. Photo by Jim Gathany, from the CDC’s Public Health Image Library

By the time you realize what has happened, it’s too late. An Anopheles gambiae mosquito can land on your skin completely unnoticed. While you continue unaware, she stealthily walks over your exposed flesh, searching, probing the surface of your skin with her proboscis until she finds a blood vessel. She then situates her body perfectly at just the right angle, hunches down, and plunges her needle-like mouthparts into your skin. Tiny pumps pull the warm, protein-rich blood into her mouth.

With every millisecond increasing her chances of exposure, she drinks as quickly as she can. Your hand isn’t the only obstacle she faces: even as she sucks, your body senses the wound and attempts to plug the hole by forming a clot. She needs your warm, nutritious blood for her eggs, so she’s not about to let your protective mechanisms interfere. To ensure her meal keeps flowing, she pumps saliva laden with anti-coagulants and vasodilators  into the wound — and that’s when it happens. That’s when the Plasmodium falciprum sporozoites that have been waiting patiently in her salivary glands enter your bloodstream. Dozens can hitch a ride in her saliva, but it only takes one to cause malaria. One single, microscopic protozoan is enough to kill you.

Responsible for the most dangerous kind of malaria and at least half of malaria cases worldwide, Plasmodium falciprum is estimated to kill somewhere between 500,000 and 1 million people every year. In recent years, the parasite has developed resistance to many of our best treatments, leaving doctors without options in the over one hundred countries where malaria is endemic. While scientists continue to research new means of treatment from vaccines to drugs, nations struggling with malaria have shifted focus to prevention. Recently, this means scientists have become particularly interested in mosquito behavior to develop better, cost-effective control mechanisms. But a new study in PLoS ONE today suggests we know less than we might have thought, and that the parasite may be influencing its host mosquitos in ways we never even imagined.

“So far, most studies of Anopheles gambiae mosquito behavior have been conducted with uninfected mosquitoes,” write the authors, “but our data demonstrate that such results may not be representative of infected mosquitoes.” Previous studies found that Plasmodium-infected mosquitos probe skin more, bite more often and ingest larger meals than uninfected ones, but the scientific team comprised of scientists from the Netherlands, United Kingdom, and United States wondered whether infected mosquitos behave differently before they land.

Many parasites with multiple hosts are known to alter one hosts’ behavior to increase transmission to the next. Toxoplasma gondii, for example, suppresses rats’ fear of cats by altering how they respond to feline smells. The research team wondered if Plasmodium could control mosquitos along the same lines, so they tested how uninfected and infected mosquitos reacted to the scent of human skin. Their results were staggeringly significant.

Figure 1 A from Smallegange et al. The total number of landings by uninfected (green bars) and P. falciparum infected (red bars) mosquitos in response to no odor (left) or human skin odor (right).

Infected Anopheles mosquitos landed on the human-scented surface more than three times as often as non-infected mosquitos. “These results suggest that malaria-infectious females are more attracted to human odors than uninfected mosquitoes,” write the authors. “This is the first indication of a change in [mosquito] behavior in response to human odor, caused by infection with P. falciparum.”

The authors hope this research spurs further study into the ways in which Plasmodium alters mosquito senses. New types of attractant smells, for example, could lead to breakthroughs in trapping technology and provide powerful allies in the struggle against malaria.

But the discovery that mosquitos act differently when infected has its downsides, too. If the parasites can change how the mosquitos smell, how much does this alter how they behave? Are the usual battery of deterrent or attractant smells less effective? Is the alluring scent enough to draw mosquitos to feed when they normally wouldn’t, making our nightly netting less meaningful? Are there any other ways that the parasite alters its host, and what do these changes in behavior mean when it comes to bite prevention?

There is a long road ahead before scientists will fully understand the complex interactions between Plasmodium and their hosts. Studies like this one reveal just how little we understand these deadly parasites of ours, and how much more we have to learn if we want to win the battle against them.

 

 
Citation: Smallegange R., van Gemert G.J., van de Vegte-Bolmer M., Gezan S., Takken W. et al. (2013). Malaria Infected Mosquitoes Express Enhanced Attraction to Human Odor. , PLoS ONE, 8 (5) e63602. DOI: 10.1371/journal.pone.0063602

  X2!

The winners of the inaugural Science Seeker Awards have been announced! My posts got nods as finalists in two categories: Best Biology Post and Best Life-in-Science Post. Thank you so much to the judges for these honors, and a huge congrats to all of the winners and other finalists. I strongly suggest reading through the list of winners and finalists, and checking out all of the fabulous posts!

Welcome to Musical Monday, where I feature an original song just for the heck of it. Want to hear more? Check out my previous musical posts, Time – And Brain Chemistry – Heal All Wounds, Biochemically, All Is Fair, and Taking Einstein’s Advice, and previous Musical Mondays Stay Near Me and As Hard As It Is.

I’ve had a song banging around in my head for awhile, and finally this weekend I took the time to get a very rough draft out. When it comes to love, everything is a gamble. So, enjoy!

You believe you are an island
You are forever alone
Waves of regret and isolation
come ashore, ashore, ashore

Walls of your creation surround you
By showing no weakness, you feel strong
You think you cannot be happy
but you’re wrong, you’re wrong, you’re wrong

You play the game with an ace up your sleeve,
so scared of losing you don’t care who you beat,
but you’ll never win no matter how much you cheat,
cuz you keep your cards to your chest, and fold when she bets

Over time the fog has lifted
There are clear skies overhead
but you hide in your darkness
my friend, my friend, my friend

You choose the path of most resistance
It’s the only path you know
But all you need is to give in
to let go, let go, let go

Still you play the game with an ace up your sleeve,
so scared of losing you don’t care who you beat,
but you’ll never win no matter how much you cheat,
cuz you keep your cards to your chest, and fold when she bets

Just close your eyes
Imagine a world where you don’t have to lie
Where you put your heart on the line
Broken and bleeding, it’s still whole
I know, I know, I know

You were not ready when I met you
Our dead love rests in peace
But I won’t be the last to believe in you
you’ll see, you’ll see, you’ll see

Just lay the cards on the table
Don’t count the chips in the end
You don’t have to be an island
You don’t have pretend
Love is worth the gamble
Oh my friend, my friend, my friend

Turn that frown upside-down — the newest Nature issue defends GMOs. Cover image provided by Nature.

Now, the top-tier scientific journal Nature has weighed in. In their “GM Crops: Promise & Reality” issue this week, several articles explore “the messy middle ground.” With titles like “Tarnished Promise” and “A Hard Look At GM Crops,” you might think they attack genetic engineering, but in fact, the entire issue does the opposite, standing in support of crop genetic engineering technologies and pleading to rethink the knee-jerk reaction against them. Even the “Hard Look” concludes, “Tidy stories, in favour of or against GM crops, will always miss the bigger picture, which is nuanced, equivocal and undeniably messy. Transgenic crops will not solve all the agricultural challenges facing the developing or developed world… But vilification is not appropriate either. The truth is somewhere in the middle.”

Which is exactly what I’ve been saying all along. 

“Over the past 50 years, improved crop varieties have contributed almost 1% each year to the gains made in worldwide agricultural productivity,” explains Christopher Whitty, chief scientific adviser at the UK Department for International Development (DFID), and colleagues in their comment piece “Africa and Asia need a rational debate on GM crops”. “To begin with an emotional debate about GM techniques is to look down the wrong end of the telescope.”

Whitty and his colleagues aren’t Monsanto shills; they’re scientists that have carefully weighed the evidence. And they’re among the majority of scientists that support GM technologies, even though they say GMOs aren’t an agricultural panacea. “Genetic engineering is not essential, or even useful, for all crop improvements,” they write. But, they come down hard on blanket bans against genetically engineered crops. “Excluding any technology that can help people to get the food and nutrition that they need should be done only for strong, rational and locally relevant reasons.” To support their case, they specifically cite three examples of GMOs — vitamin A-boosted golden rice, poo-borer-resistant cowpea, and water-efficient maize — that they consider “potential life savers.”

They also make special note of the western world’s privileged status when it comes to debating GMOs, and argue that developing countries shouldn’t simply follow the leader when it comes to genetic technology policies. “It makes little sense for decisions on GM crops to be overly influenced by European perspectives… where the benefits of better crop yields are slight, the risks (although largely theoretical, and in some cases, arguably irrational) may dominate in a risk–benefit analysis.”

Meanwhile, in a different comment piece, Fusuo Zhang and colleagues describe how “driven by an urgent need to both produce more food and lessen the environmental impact of agriculture — and with more money to address the problem than most — Chinese scientists are working out how to push crop yields close to their biophysical limits.” And, of course, GMOs are playing an important role in these efforts to improve efficiency and sustainability.

“The development of new crop varieties and hybrids is one of several areas of fundamental research,” the authors write, “with transgenic technology becoming an increasingly important element in recent years.” The use Bt cotton as an example (the first GM crop approved for commercial use in China), citing that, with it, farmers have increased yields by nearly 6% and reduced the use of insecticides by around 80% in the past 8 years. In spite of the Chinese public’s wariness about genetic engineering, the government poured almost $4 billion US into a 12-year GM research and development initiative. “In the face of climate change, pushing yields to the limit while sparing resources and reducing environmental consequences is a crucial goal for all,” they conclude.

And the next generation of GM crops are on their way, explains Daniel Cressey in his news feature “A New Breed.” “New tools offer unparalleled precision in editing genes,” he explains. “Some of these crops will tackle new problems, from apples that stave off discolouration to ‘Golden Rice’ and bright-orange bananas fortified with nutrients to improve the diets of people in the poorest countries.”

The main goal of GM researchers now: use what you’ve already got. “The real power of these techniques lies in the ability to confer new traits by modifying native plant genes,” Cressey explains. He writes about researchers that are using modifications to a plant’s actual genes, not the insertion of genes from other species, to combat common problems. Cressey notes that using the plants own genetic material “could conceivably reduce the public disquiet over GM foods.” “US regulators have already suggested that organisms modified with the newer techniques such that they contain no DNA from other species will be treated differently from conventional GM organisms,” he explains.

One of the many applications of transporters cited in Schroeder et al.’s perspective: barley engineered for enhanced zinc content. Around two billion people suffer from iron and zinc deficiencies worldwide. Image courtesy of The John Innes Centre

Nature further has an entire perspective article dedicated to one way in which scientists may be able to achieve the lofty goal of improving without adding: alterations in membrane transporters. “Transport proteins embedded within membranes are key targets for improving the efficiency with which plants take up and use water and nutrients,” explain the international team of 11 scientists led by Julian Schroeder, UC San Diego biology professor. The new wave of genome sequencing, they say, has led to incredible leaps in understanding of the natural genetic diversity of plant membrane transporters, which can be exploited through conventional breeding or genetic engineering.”Just as our cell phones will need more advanced technology to carry more information, plants need better or new transporters to make them work harder on existing agricultural land,” said Dale Sanders, director of the John Innes Centre in the U.K. and a corresponding co-author of the paper, in a press release. “We can make plants better at finding and carrying their own chemical elements.” By tinkering with these genes, scientists can improve nutrient content and increase drought, flood, or salinity tolerance. “We expect that research into fundamental mechanisms of plant membrane transport processes will continue to produce surprises and breakthroughs that will provide new avenues towards a more sustainable and productive agriculture in the face of impending challenges,” write the authors.

That’s not to say that using native plant genes should be the only way to engineer better crops. There is plenty of good being done with cross-species gene transfer, too. Cressey discusses how non-agribusiness researchers are focusing on locally used plants instead of big money makers, hoping to improve crops for developing countries. Nutritional enhancement is a common goal, including crops like golden rice and fortified bananas. These researchers are trying to solve real global issues, whether or not Monsanto and other large agricultural companies are backing them.

Even the harshest article in this new Nature issue defends GM crops. In “A Hard Look At GM Crops,” Natasha Gilbert examines the myths and truths of the GM debate. Is Bt cotton leading to suicides in India? Nope. “The claim, based on an increase in total suicide rates across the country in the late 1990s, has become an oft-repeated story of corporate exploitation since Monsanto began selling GM seed in India in 2002,” Gilbert explains, but the fact is “there has been essentially no change in the suicide rate for farmers since the introduction of Bt cotton.” Are GM crops causing superweeds? Well, yes, but that’s not the whole story. “Twenty-four glyphosate-resistant weed species have been identified since Roundup-tolerant crops were introduced in 1996,” Gilbert explains, “But herbicide resistance is a problem for farmers regardless of whether they plant GM crops. Some 64 weed species are resistant to the herbicide atrazine, for example, and no crops have been genetically modified to withstand it.”

The end result of Gilbert’s “Hard Look” is a hard look at the arguments against GMOs, not the GMOs themselves. As she explains, “These controversial case studies show how blame shifts, myths are spread and cultural insensitivities can inflame debate.”

The point being made over and over by these pieces is that GM crops are a part of the future of agriculture, and they should be. As fellow Discover blogger Keith Kloor has pointed out many times before, “Unfortunately, the public GMO discourse is dominated by phony, pseudoscientific claims advanced by ideologically motivated activists and their enablers in the media.” Kloor comes down hard on the media’s willingness to portray GMOs as dangerous in spite of a complete lack of any scientific evidence whatsoever. “In truth,” he writes, “the uncontrollable spread of disinformation about GMOs is what’s really contaminating the environment.”

I completely agree. As I’ve said before , the future of agriculture needs to use all tools available to tackle the growing problems of malnutrition, population growth, and ecological impact. If we universally apply the same methods globally, we are destined to fail both in terms of efficiency and sustainability. It is only through the breakdown of arbitrary and variable distinction between methodologies like “organic” and “conventional,” scientific rigor in our approach to studying technologies and methods, and integration of a variety of practices that we will achieve our ultimate goal of a bright future both agriculturally and ecologically.

I’m glad to see such a prominent journal focus on this hot-button issue, especially with such staunch defense of technology. Genetic engineering isn’t the enemy of sustainable agriculture, even if Monsanto or other agri-businesses are. The technology itself is unbiased, and can be used to revolutionize food production globally. To blanket attack technologies with the potential to help billions while lessening our impact on the rest of the Earth is counter-productive to everything the environmental movement stands for. It’s time we stop villainizing GMOs, and start using science and technology to secure a healthy, sustainable future.

Citations:
The Nature special issue: http://nature.com/gmcrops

Schroeder J., Delhaize E., Frommer W.B., Guerinot M.L., Harrison M.J., Herrera-Estrella L., Horie T., Kochian L.V., Munns R., Nishizawa N.K., Tsay Y.-I. & Sanders, D. (2013). Using membrane transporters to improve crops for sustainable food production, Nature, 497 60-66. DOI: 10.1038/nature11909

A lot, actually.

Michael Kosinski and his colleagues from UC Berkley recently investigated just how much Facebook activity reveals about a person. They wanted to know if a user’s age, gender, sexual orientation, or political beliefs could be inferred from their “likes”, even if such personal details were not provided. Using the myPersonality Facebook app, the team obtained 58,466 volunteers who provided demographic data as well as a list of their likes. The average volunteer liked 170 different pages, musicians, etc. They then used statistics to determine if those likes predicted a suite of personal variables, from male/female to intelligence level. Their results were staggering.

Prediction accuracy of simple traits, according to Kosinski et al. 2012

The algorithm they created could predict race and gender with over 90% accuracy. Even religion, political party affiliation, and sexual orientation could be predicted with over 80% accuracy. In the case of sexual orientation, this result was truly unexpected, as less than 5% of users were connected to explicitly gay groups.

From the pages you like, the computer could predict whether you drink, smoke, or use drugs with more than 60% accuracy. Likes also strongly correlated with age. In fact, your likes reveal so much about who you are that the team could predict whose parents divorced before they were 21 with 60% accuracy! “Although it is known that parental divorce does have long-term effects on young adults’ well-being,” write the authors, “it is remarkable that this is detectable through their Facebook Likes.”

Correlation between complex traits and likes, from Kosinski et al. 2012

Even personality traits, which don’t fall into neat A or B categories, were well correlated to likes. And the more likes you have, the better the computer algorithm is at figuring you out.

Simply put by the authors: “A wide variety of people’s personal attributes, ranging from sexual orientation to intelligence, can be automatically and accurately inferred using their Facebook Likes.”

This could have many upsides, including well-tailored ads, apps and such that really do suite you. But, the predictability of individual traits may have considerable negative implications as well. “It can easily be applied to large numbers of people without obtaining their individual consent and without them noticing,” caution the authors. “Commercial companies, governmental institutions, or even one’s Facebook friends could use software to infer attributes such as intelligence, sexual orientation, or political views that an individual may not have intended to share.”

In a worst-case scenario, the release of such information could be serious. With online harassment a constant issue, hate groups could use likes to target victims, even when an individual takes measures to be discreet — for example, the predictability of sexual orientation may make users vulnerable, even though individuals don’t have explicitly homosexual likes. And as the digital revolution continues to change how we interact in modern society, Facebook likes are hardly the only information that may be used for such purposes. It is becoming more and more difficult to keep track of our online footprints, and thus the information we reveal about ourselves may be harder and harder to control.

The authors acknowledge that the risks of this may deter people from integrating with digital technologies.”It is our hope, however, that the trust and goodwill among parties interacting in the digital environment can be maintained by providing users with transparency and control over their information,” they conclude, “leading to an individually controlled balance between the promises and perils of the Digital Age.”

Citation: Kosinski M., Stillwell D. & Graepel T. (2013). Private traits and attributes are predictable from digital records of human behavior, Proceedings of the National Academy of Sciences, 110 (15) 5802-5805. DOI: 10.1073/pnas.1218772110

What does your voice say about you?

Our voices communicate information far beyond what we say with our words. Like most animals, the sounds we produce have the potential to convey how healthy we are, what mood we’re in, even our general size. Some of these traits are important cues for potential mates, so much so that the sound of your voice can actually affect how good looking you appear to others. Which, really, brings up one darn good question: what makes a voice sound sexy?

To find out, a team spearheaded by University College London researcher Xi Yu created synthetic male and female voices and altered their pitch, vocal quality and formant spacing (an acoustics term related to the frequencies of sound), the last of which is related to body size. They also adjusted the voices to be normal (relaxed), breathy, or pressed (tense). Through several listening experiments, they asked participants of the opposite gender to say which voice was the most attractive and which sounded the friendliest or happiest.

Labroides dimidiatus feeding off a plexiglas plate in the lab at the Lizard Island Research Station. Photo courtesy of Simon Gingins

On the surface, cleaner wrasses seem like real nice fish. They set up their little cleaning stations on patches of reef, offering to eat any external parasites that other fish might have picked up. It’s a pretty sweet deal for both sides — the cleaners get a tasty meal, while the other fish get rid of pests. But not all of these do-gooders deserve their squeaky clean reputation. Every once in a while, a cleaner wrasse will take advantage of the situation and take a bite out of the tasty mucus coating of its client instead of eating parasites like it’s supposed to. This cheating behavior has fascinated scientists, who want to uncover what drives the cleaners to cheat, and what keeps them in line.

“They are a very good system to study cooperation between unrelated individuals,” explains Simon Gingins, who is studying the cooperation between cleaners and their clients for his PhD. Cleaner fish are dependent on their clients to eat, as they’re not fast enough to take bites out of fish that don’t sit and wait. “Their cooperative behavior is central to their life: most of what they do everyday is to interact with other fish species to obtain their food.”

Of course, the wrasse would prefer to cheat. Fish mucus is a much tastier food item to the fish, and when given the option, they prefer mucus over parasites. But for the mutualistic relationship to have evolved, there must be mechanisms in place which limit bad behavior. Previous studies have suggested that a complex interplay between reputation (switching to non-cheating cleaners), punishment (chasing/eating the cleaner), and temptation prevents cleaners from cheating all the time. But Gingins wondered if the answer might be much simpler.

Not all clients can threaten the cleaners, for example. Herbivorous fish can’t eat a cleaner, and thus their only way of responding to a cheater is to swim off as quickly as possible. This gave Gingins a perfect set-up for testing cleaner behavior. Using plexiglass plates to mimic client fish, Gingins and his colleagues offered cleaner wrasses mucus or parasites, adjusting how quickly the plate is pulled away if the cleaner chooses mucus. “Basically, we made the plates “behave” like a client fish would,” explains Gingins. “It would stay long as the cleaner ate the less-preferred food type (corresponding to eating parasites in real life) but would be removed as soon as the cleaner ate the preferred type (corresponding to taking a bite of mucus in real life).” Furthermore, they varied the quality of the mucus, setting up a high-temptation and a low-temptation scenario. Then then watched how the cleaners reacted when the fake clients ran away.

Cleaner wrasse Labroides dimidiatus interacting with a Flowery cod Epinephelus fuscoguttatus at “Cod Hole”, Great Barrier Reef, Australia. Photo courtesy of Simon Gingins.

The cleaners reacted exactly how Gingins thought they would: when temptation was low and the client was quick to pull away, the cleaners cheated less. But, when the temptation was high and the client didn’t run as fast, the cleaners were perfectly content to cheat. These data suggest a very simple interaction is enough to encourage cooperation. “What is interesting here is that power (the control over interaction duration) is a very simple mechanism to stabilise cooperation, as unlike reciprocity or partner switching, it does not rely on potentially iterated interactions,” explains Gingins. “While more complex mechanisms such as punishment or reputational effects may receive more attention from researchers, rather simple partner control mechanisms may often be responsible for stable cooperation in nature.”

Interestingly, temptation drove behavior even more than the sanction of early termination. But, the scientists point out, in nature, there is probably low temptation to cheat: while cleaners preferred mucus over the parasites in a choice experiment, they regularly ate the latter anyway.

To further examine the evolution of the cooperative behavior, the team tested a different species — a close relative that isn’t a cleaner — with the exact same experiment. That species failed to modify it’s behavior: it always ate according to its preference. “It thus appears that this strategic behavior cannot be performed by any fish,” says Gingins, “but has evolved for the particular ecology of cleaners.” To modify their behaviors, the cleaners had to do something truly special: they had to learn. “As the experiments involving plates and food represent learning tasks, the cleaner wrasse’s superior performances are linked to adaptations in the cognitive machinery,” explain the authors.

Ultimately, studies like this one shed light on how species cooperate. While complex interactions may play a role over time, these results suggest that simpler mechanisms may be enough to drive cooperation, explaining how such relationships evolve in the first place.

 
Citation: Gingins S., Werminghausen J., Johnstone R.A., Grutter A.S. & Bshary R. (2013). Power and temptation cause shifts between exploitation and cooperation in a cleaner wrasse mutualism, Proc. R. Soc. B , 280 (1761) DOI: 10.1098/rspb.2013.0553

I was less than 20 miles outside of Boston on September 11th, 2001. One of the kids that held me as I cried then ran today in Boston.

Just a week before, he and I chatted over sushi here in Hawaii. He had come out for a conference, and we talked for hours, catching up on everything that had changed in the decade or so since we saw each other last. We had been on the cross country team together briefly in high school (when I foolishly attempted to become a runner). Unlike me, he’s a natural runner. Always one of the first to finish for our school, his passion for the sport has only grown over time. He gushed to me about the upcoming marathon, with excitement lighting his eyes. Running the Boston Marathon is a point of pride for any runner. Since you have to qualify to get in, even being allowed to run is considered an honor. But today, the finish line normally filled with sweat, relief and joy became a gruesome crime scene.

Thankfully, my friend finished long before the bombs went off.

When I heard about what happened, my gut immediately tightened, and I erupted into tears. I have countless family and friends in the Boston area, and immediately, I started the mental list of who I needed to check in on. The classmate that ran — check. A friend who works in the area — check. One of my closest friends and his partner — check. Classmates, colleagues, family, friends — check, check, check, check. I turned to facebook and twitter, relieved to see so many updates from people who are safe, telling their loved ones that they’re ok. Too many, though, were stories of near misses. People that happened to be working from home instead of the office, runners that finished early or never got the chance to, friends that almost went to cheer them on.

I cannot begin to understand the mind of someone who would do something like this, though certainly scientists have tried.

Some are questioning whether what happened should be labeled a terrorist attack. When a series of bombs explode in streets crowded with innocent people, though, there can be no mistaking the goal. Whoever placed these bombs wanted to hurt us. They timed the attack not to hit the first place racers, but when many more would be crossing the finish line. They blew up crowds of spectators and athletes, regardless of age, sex, race or religion. They stole lives and limbs. They took a day of celebration and forged one of gruesome violence. For whatever reason, whatever cause they sought to further or message they sought to send, they meant to incite terror. They wanted to fill our hearts with fear and rage, to twist our thoughts to hatred and retaliation.

We cannot let them have that. We cannot let them win.

Reactions like Erik Rush’s won’t help anything. We don’t know who chose to commit this terrible act, but we will, and when we do, they will be punished. As Obama promised, “make no mistake, we will get to the bottom of this… We will find out who did this, and we will hold them accountable.” In the meantime, turning on anyone before those facts come in, blaming religious or political groups without any evidence, or making broad threats will only serve to worsen what has happened. If there is one thing that horrific events like this one teach us, it is that hatred is a powerful and destructive force. No good can come of letting ourselves be blinded by it. We will not, as a nation, be coerced to become as twisted as those who placed the bombs today. We cannot.

What I have seen more than anything over the past few hours are outpourings of love and support. People around the world are expressing their honest concern and hope for the people of Boston and the families and friends of everyone involved. That is what we need.

There will always be bullies. There will always be extremists whose thoughts are so distorted by hate that they lose their very humanity, making them capable of unspeakable crimes. There will always be tragedies, and though we hope to prevent as many as we can, we will never be able to prevent them all. But there will also always be reasons to hope and love. There will always be everyday heroes, from the first responders who bandaged at the blast site to the nurses and doctors still tirelessly striving to save lives. There will always be those who risk their own safety to help those in need. There will always be selfless, kind, caring people, and those people far outweigh the few monsters who commit acts like this.

My heart is with you, Boston. Though my body is 6,000 miles away, my heart is home.

Links:

• Can’t find someone? Google has set up a people finder to track down missing loved ones
• Anyone trapped by the race or living in the area with a couch to spare, go to the Boston Globe-run form to let others know
• Mayor’s hotline for people looking for friends/family: 617-635-4500
• Anyone with videos/pictures of the route call 800-494-TIPS or the FBI at 1-800-CALL-FBI (prompt #3)