What we can learn from the clones that walk among us —

Genetically speaking, identical twins ought to be two copies of the same person. Environmentally speaking, if the twins grow up together, they ought to even be influenced by the same things. But if you actually pay attention to identical twins, they aren't identical in personality or interests. How do naturally occurring clones become individual people? That's the subject of a mouse study that Scicurious writes about on her blog. Fascinating stuff. — Maggie •

The power of the swarm —

At Wired, Ed Yong has an incredible long-read story about the researchers who are figuring out how and why individual animals sometimes turn into groups operating on collective behavior. That research has implications far beyond the freakish, locust-filled laboratories where Yong's story begins. Turns out, bugs and birds can teach us a lot about the brain, cancer, and even how we make predictions about our own futures. — Maggie •

Meet Pavlov's dogs —

Ivan Pavlov had at least 35 dogs that were involved in his Nobel Prize-winning on behavior and conditioning. But only one of them was stuffed and preserved in the Pavlov Museum. — Maggie •

Underwater, Antarctica's Weddell seals are fast-moving, graceful predators, catching and eating as much as 100 pounds of food per day. They dine on squids and fish and have been known to enjoy the occasional penguin or two.

On land, they are hilariously ineffectual blobs of jelly.

You can see that dichotomy in action in this great (and long) video made by Henry Kaiser in Antarctica. Following the adventures of a baby seal on the ice and under the water, the video is peaceful, meditative and reminds me a bit of the sort of old-school Sesame Street video that would build simple, kid-friendly narratives out of nature footage and music. (The music, by the way, was written and performed by Henry Kaiser, as well.)

Despite their poor performance in land-based locomotion, Weddell seals actually live on the ice, descending into the water to hunt and mate and swim around. They use natural holes in the ice to get from above to below and back, but they also work to maintain those holes and often use their teeth to chew at the edge of the ice and make a small hole larger. At about 13 minutes into the video, you can watch a seal doing just that — rubbing its head back and forth to enlarge an opening in the ice.

And why hang out on the ice, to begin with? Simple. In the water, seals are, themselves, potential dinners for larger creatures. On land, they have no natural predators at all and can safely bask in the sun, lying on their cute and chubby bellies for so long that their body heat hollows out divots in the ice.

I really enjoyed reading a recent story in The New York Times Magazine about attempts to understand extreme longevity — the weird tendency for certain populations to have larger-than-average numbers of people who live well into their 90s, if not 100s.

Written by Dan Buettner, the piece focuses on the Greek island of Ikaria, and, in many ways, it's a lot like a lot of the other stories I've read on this subject. From a scientific perspective, we don't really understand why some people live longer than others. And we definitely don't understand why some populations have more people who live longer. There are lots of theories. Conveniently, they tend to coincide with our own biases about what we currently think is most wrong with our own society. So articles about extremely long-lived populations tend to offer a lot of inspiring stories, some funny quotes from really old people, and not a lot in the way of answers.

Buettner's story has all those elements, but it also proposes some ideas that were, for me, really thought provoking. After spending much of the article discussing the Ikarian's diet (it's low in meat and sugar, high in antioxidants, and includes lots of locally produced food and wine) and their laid-back, low-stress way of life, Buettner doesn't suggest that we'll all live to be 100 if we just, individually, try to live exactly like the Ikarians do. In fact, he points out that other communities of long-lived individuals actually live differently — Californian Seventh-Day Adventists, for instance, eat no meat at all and don't drink, and they live with the normal stresses of everyday American life.

What these groups do have in common, though, is a strong social infrastructure that ties people to each other emotionally and connects individual choices to a bigger community lifestyle.

Read the rest

Hey guys! Check out this great JPEG I found last month. The caption was created by physics blogger Matthew Francis, and I've really been looking forward to sharing it with you!

In totally unrelated news, I just read a story by Stephanie Pappas at LiveScience.com, all about evolutionary psychologists' ongoing attempts to determine whether human females prefer our men hairy or smooth and, if so, why. Pappas' story covers a recent study that tried (and failed) to support one hypothesis: Women like hairless guys because we somehow know that hairy chests could be havens for parasites. A Sean Connery-like thatch is just one more place for lice to hang out.

Studying the preferences of women in two different cultures — Turkey and Slovakia — the researchers expected to find that Turkish women were more likely to choose hairless men because that country has long had higher rates of parasite-transmitted disease. Instead, they found that women in both countries overwhelmingly preferred their gentlemen in a less-wooly state.

The headline on the LiveScience article: "Why Women Don't Fall for Hairy Guys Remains A Scientific Mystery".

Thanks to Joanne Manaster for the inspiration!

Time is relative. Remember how each day in grade school (especially summer days) seemed to last for an eternity? Ever notice how it seems to take forever to travel a new route on your bike, while the return trip along the same path is done in the blink of an eye?

Turns out, both of those things are connected and they have important implications for the nature of memory. There's a great summary of the science on this up at The Irish Times. It's written by William Reville, emeritus professor of biochemistry at University College Cork.

The key issue, according to Reville, is that the amount of information your brain can store during a given time period isn't really dependent on the length of that time period. You could store up a lot of new information during 10 minutes of a really interesting lecture. You might store only a little new information during 10 minutes of walking your dog along a path you know very well.

The higher the intensity, the longer the duration seems to be. In a classic experiment, participants were asked to memorise either a simple [a circle] or complex figure . Although the clock-time allocated to each task was identical, participants later estimated the duration of memorising the complex shape to be significantly longer than for the simple shape.

... [H]ere is a “guaranteed” way to lengthen your life. Childhood holidays seem to last forever, but as you grow older time seems to accelerate. “Time” is related to how much information you are taking in – information stretches time. A child’s day from 9am to 3.30pm is like a 20-hour day for an adult. Children experience many new things every day and time passes slowly, but as people get older they have fewer new experiences and time is less stretched by information. So, you can “lengthen” your life by minimising routine and making sure your life is full of new active experiences – travel to new places, take on new interests, and spend more time living in the present.

I think this also has some implications for my exercise routine. I am well aware that my ability to run any distance at all is heavily dependent on psychological factors. I am not one of those people who likes to go running in new places, along unfamiliar trails, because it has always made me feel like the distance was much, much longer — and, consequently, leads me to stop running and start walking sooner than I actually have to. I've had a lot more luck running on tracks and elliptical machines—situations where it seems to be easier for me to get into a zone and lose track of time. When I run that way, it's my physical limitations that matter, not my psychological ones.

Of course, I know a lot of people who feel exactly the opposite. Maybe, for those people, running in a routine situation, like a track, makes them start to think more about their day or what's going on around them, and processing all that information makes the workout seem longer. I'm not sure. But this is awfully interesting.

Read the rest of William Reville's piece at The Irish Times

Via Graham Farmelo

Image: RUN Hills Pullover in action!, a Creative Commons Attribution (2.0) image from lululemonathletica's photostream

Xenophobia is neither the fear of Xeni, nor of Xena. Rather, it's more about knee-jerk mistrust, dislike, and hatred for people who aren't part of your group. We've come to associate it with not liking people from other countries, but it applies to smaller-scale, less formal tribalism, as well.

Over at the Scientific American blogs, science writer and biologist Rob Dunn talks about some of the theories for why something as seemingly antisocial as xenophobia could have been beneficial to our ancestors—at least under certain circumstances. The key, he says, might be disease. Not cooperating between groups, refusing to share resources, and generally going out of your way to avoid strangers makes sense if those strangers are infected with something that could kill you.

If I'm understanding Dunn correctly, the research and theorizing on this topic isn't saying xenophobia is good. Nor is it saying that all xenophobia grows out of a conscious, reasonable fear of disease. It's more like, the times when xenophobia did turn out to be coincidentally beneficial happened to reward people who were more likely to pass on xenophobic tendencies to their offspring (whether those tendencies were genetic or cultural is hard to say). Thus, the tendency continues, even in situations where it's actively detrimental. And Dunn points to an interesting recent study that showed deadly white-nose syndrome is causing xenophobic-esque changes in the behavior of bat populations.

Although it looked as though the little brown bats and several other species might soon face extinction, at least in some regions and perhaps even in North America, the little brown bats have begun to rebound in some places, albeit modestly. A new paper out this week takes notice of one of the reasons they appear to be rebounding, the bats are avoiding each other. Little brown bats (at least historically) tend to roost in large, groups, one next to the other, bumping fuzzies as it were. But not anymore. More and more, this new study, led by Kate Langwig, a graduate student at Boston University, suggests, the bats are spreading themselves out in their roosting caves, their hibernacula. Once, they clumped, warming themselves around the tiny fires of their bodies. Now, they go it alone.

Langwig’s results are preliminary, as she and her colleagues are the first to admit. She has measured the change in the bat roosting (and abundance) before and after the arrival of the disease, but she has not really studied the behavior of the bats and how it is they come to be spaced apart. Yet, the bats the are important from the perspective of the basic biology and conservation of the bats and so there remains much to do and much that can be done. For example, it would be good to know if the probability of transmission of the disease really goes down when the bats are further apart. It would also be interesting to figure out if the same individuals that were once nuzzling up next to each other, are now hanging out on their own.

Read the rest of Rob Dunn's post on xenophobia and disease

Via Discover's 80 Beats blog

New evidence suggests people aren't nearly as dickish on the Internet as you might think —

A new study, published in the journal Nature, provides evidence that the way people communicate with each other doesn't change very much between offline and different kinds of online situations, including chat rooms—even if the people are chatting anonymously. The catch: This only holds true in places where the same people are coming back to chat over and over. (Via Colin Schultz) — Maggie •

We've had a couple of posts recently about a hypothesis that links the current increase in obesity with an increase in easy access to foods that are designed to trigger reward systems in the human brain. Basically: Maybe we're getting fatter because our brains are seeking out the recurrent reward of food that makes us fat. Scientist Stephan Guyenet explained it all in more detail in a recent guest post.

It's an interesting—and increasingly popular—idea, though not without flaws. To give you some context on how scientists are talking about this, I linked you to a blog post by Scicurious, another scientist who wrote about some of the critiques of food reward and related ideas. In particular, Scicurious questioned some of the implicit connections being made here between body size and health, and eating patterns and body size.

She also talked about another critique, one which came up in a recent article in the journal Nature Reviews Neuroscience. If people are gaining weight because they're addicted to eating unhealthy foods, we ought to see some evidence of that in the way their brains respond to those foods. After all, brains respond to many physically addictive substances in special ways. But we don't see that with junk food. So does that invalidate the hypothesis?

Stephan Guyenet doesn't think it does. In a recent email to me, he explained that he thinks the food reward hypothesis is a bit more nuanced, and can't really be described as "food addiction". At least, not the same way that cigarettes or heroin are addictive.

Addiction is the dependence on a drug, or behavior, despite clear negative consequences. Drug addiction is associated with characteristic changes in the brain, particularly in regions that govern motivation and behavioral reinforcement (reward), which drive out-of-control drug seeking behaviors. Some researchers have proposed that common obesity is a type of “food addiction”, whereby drug addiction-like changes in the brain cause a loss of control over eating behavior. Hisham Ziauddeen and colleagues recently published an opinion piece in Nature Reviews Neuroscience reviewing the evidence related to this idea.

The review concluded that there is currently not enough evidence to treat obesity as a “food addiction”. I agree, and I doubt there ever will be enough evidence. However, this does not challenge the idea that food reward is involved in obesity, an idea I described in a review article in JCEM, on my blog (1, 2), and my recent Boing Boing piece.

The reward system is what motivates us to seek and consume food, and what motivates us to choose certain foods over others. To begin to appreciate its role in obesity, all we need is a common sense example.

Why do some people drink sweetened sodas between meals, rather than plain water? Is it because sodas quench thirst better than water? Is it because people are hungry and need the extra calories? If so, why not just eat a plain potato or a handful of unsalted nuts? The main reason people drink soda is that they enjoy it, plain and simple. They like the sweetness, they like the flavor, they like the feeling of carbonation on the tongue and the mild stimulation the caffeine provides. It’s the same reason people eat a thick slice of double chocolate cake even though they’re stuffed after a large meal. The reward system motivates you to seek the soda and cake, and the hedonic (pleasure) system encourages you to keep consuming it once you’ve begun.

But is this the same as addiction? If I took a person’s cola away, would they get the shakes? Would they break into a convenience store at night to get a cola fix? I’m going to say no.

I agree with Ziauddeen and colleagues that the evidence at this point is not sufficient to say that common obesity represents food addiction, and I appreciate their skeptical perspective on the matter. In obesity, as in leanness, the food reward system appears to be doing exactly what it evolved to do: seek out energy-dense, tasty food, and strongly suggest that you eat it. The problem is that we’re increasingly surrounded by easily accessible, cheap, commercial food that is designed to hit these circuits as hard as possible, with the goal of driving repeat purchase and consumption behaviors. Our brains are not malfunctioning; they’re reacting just as they’re supposed to around foods like this.

I've been doing periodic appearances on Sex is Fun, a sex-positive podcast aimed at providing fun, informative sex ed. for grown-ups. Last time I was on the show, we talked about some funny animal sex studies and what they can and can't teach you about human sexual behavior. This time around, we talked about a couple of recent studies focusing on sociology and sex.

In particular, we focused on a study from last fall that surveyed students at the University of Kansas to find out how men's and women's internalized sexism affect their relationships with each other. If you've ever watched one of those shows about so-called "pick up artists" and wondered, "Who the hell are the women falling for this crap!?", then this is the show to listen to.

Check out the podcast at the Sex is Fun site!

Image: IMG_9459, a Creative Commons Attribution (2.0) image from jon_knox's photostream.

"My Favorite Museum Exhibit" is a series of posts aimed at giving BoingBoing readers a chance to show off their favorite exhibits and specimens, preferably from museums that might go overlooked in the tourism pantheon. I'll be featuring posts in this series all week. Want to see them all? Check out the archive post. I'll update the full list there every morning.

You've seen a lot of good taxidermy this week, but nothing quite like this. Renee Mertz sent me this photo of a diorama at Vienna's Naturhistorisches Museum, which depicts a group of butterflies greedily feeding off the carcass of a dead piranha.

This is not a spot of whimsy, people. This kind of thing really does happen. In fact, you can watch a real-life example (with a less-threatening fish substituted in for the piranha) in a video taken in Alabama's Bankhead National Forest.

The good news: The butterflies are not really carnivorous, per se. The bad news: What they're actually doing is still pretty damn creepy.

It's called "puddling" or "mud-puddling". The basic idea works like this: Butterflies get most of their diet in the form of nectar. They're pollinators. But nectar doesn't have all the nutrients and minerals butterflies need to survive, so they have to dip their probosces into some other food sources, as well. Depending on the species of butterfly, those other sources can include: Mineral-rich water in a shallow mud puddle, animal poop, and (yes) carrion.

When butterflies puddle over a dead fish, though, they aren't biting off chunks. Instead, they're essentially licking the dead fish—going after salt and minerals that seep out of the dead animal as it decomposes. Bonus: Some butterflies also like to lick the sweat off of humans. And a few species of moth have been documented sucking blood and tears for living animals, including humans.

This is simply breathtaking.

In the video, researchers pump 10 tons of concrete down an ant hole and then slowly, carefully excavate the site to see what an ant colony looks like. The result is an intricate structure, equivalent in labor to humans building the Great Wall of China.

And then you think, "Oh, and we just pumped 10 tons of concrete down it. Oh. We're ... kind of assholes sometimes, aren't we?" Sorry ants. Sants.

Via Richard Martyniak