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An Egyptian fruit bat aims for an apple (image courtesy of Yossi Yovel)

The Egyptian fruit bat (Rousettus aegyptiacus) pinpoints its meal with its sonar not by aiming in front but by “looking” off from side to side, according to a study in a recent issue of Science.

With sonar, a bat (or whale or submarine) will emit a sound that is reflected off nearby objects. Those sound waves are altered by the objects, and the bat can use those changes to gain information about what the object is and its distance and direction. There are two strategies for sonar detection: A sonar beam that is sent directly forward, which returns more information overall, or a signal that hits objects on an angle, which can give more precise information.

Mathematically, strategy number two is the best strategy, and that is the one that Egyptian fruit bats use. The researchers suggest that such a strategy tradeoff may be involved in other detection methods, such as smelling, vision and hearing.

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Like humans, bonobos will share (courtesy of flickr user tim ellis)

Sharing may seem like a small thing—we do it all the time. There’s the neighbor who bakes you cookies or the co-worker who makes an extra cup of coffee for you. But sharing has been thought to be a uniquely human trait, not to be found in the animal world. For example, chimpanzees, our closest relative, won’t share food. But what about bonobos, the chimp’s more peaceful cousin?

Brian Hare, from Duke University, and Suzy Kwetuenda of Lola ya Bonobo, a bonobo sanctuary in Congo, conducted a small experiment with multiple pairs of bonobos living at the sanctuary. They placed one bonobo in a room with some food. That bonobo could then choose to eat all of the food itself or let in the other bonobo from an adjacent room and share the bounty (see video below).

More often than not, the bonobos chose to share their food. “Subjects preferred to voluntarily open the recipient’s door to allow them to share highly desirable food that they could have easily eaten alone–with no signs of agression, frustration or change in the speed or rate of sharing across trials,” the researchers write in an article that will appear in the March 8 issue of Current Biology.

The animals weren’t sharing because of kinship—the bonobos weren’t related—or to pay off past debts, since even bonobos that were complete strangers shared. Hare and Kwetuenda suggest that the bonobos were sharing “in an attempt to receive favors in the future from the recipients or due to a more altruistic motivation,” much the same reasons that humans will share.

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Speed skating requires technique, good physiology and state-of-the-art technology (courtesy of flickr user daniel_dimarco)

I’ve always been a fan of the Winter Olympics, but a bout with the flu in 2002 that kept me at home watching TV for a week made me an addict. But it’s not just about watching hours of skiing and skating. There’s science, too, and it seems to be everywhere this year. Here are some good resources and news stories that find the science in the Winter Games:

Science of the Olympic Winter Games: This site, from NBC Learn and the National Science Foundation, has videos explaining a host of subjects, from the physics of the hockey slapshot to how friction works in curling. (Lesson plans are available here.)

Winter Olympics: Sport & Science: Montana State University provides mini-courses on three Olympic themes–sports nutrition, physics and biomechanics, and physiology and psychology.

The New York Times Learning Network blog has suggestions for a 2010 Winter Olympics Teaching and Learning Extravaganza. And Teachervision has even more resources.

In recent news, CTV in Canada explored The Science of Long Track Speed Skating and found that a winning skater must combine good technique with physiology and technology.

Wind resistance plays a role in any race, including skeleton, that crazy sport in which “sliders” hurl themselves down the tube-like course head first. To get an advantage this year, the U.S. team studied sled forces in a high-tech simulator, as Scientific American reported yesterday.

How about the Science of Curling? Apparently the sweeping is very important and even though it might not appear taxing, curlers can develop fatigue.

And USA Today reexamined a 2005 study that had found that red-clad boxers at the Olympics did better than their fellows in blue. It turns out that a key assumption in the study–that red and blue attire was randomly assigned–was wrong. On second look, wearing red didn’t affect the outcome of a bout.

Cute kitty (courtesy of flickr user skipnclick)

The Lunar New Year was on Sunday, welcoming in the year of the Tiger. The World Wildlife Fund has taken that as a sign to launch their own tiger campaign “Tx2: Double or Nothing” with the aim of doubling the wild tiger population by 2022, the next year of the Tiger.

Like many large predator species around the world, the tiger (Panthera tigris) isn’t doing very well. There are only around 3,200 left in the wild in Asia. In the past 70 years, three subspecies of tiger have gone extinct and a fourth hasn’t been seen in wild for the past 25 years. WWF notes a list of threats that includes: paper, palm oil and rubber plantations that are replacing forests in Indonesia and Malaysia; dams along the Mekong River that fragment tiger habitat; trafficking in tiger bones, skins and meat; and climate change.

WWF has the support of the 13 nations where tigers still roam, but it remains to be seen if their campaign will see any success. With the human population growing, will there still be room for these cute but deadly kitties? Or will they become the second mythical creature–after the dragon–on the lunar calendar?

A little more than a year ago we asked: Who Was More Important? Abraham Lincoln or Charles Darwin? It seems like an odd question, but since they were both born on the same day—February 12, 1809—we thought we’d give the thought experiment a try. Two Smithsonian editors argued for Lincoln and two others for Darwin. We then asked you, our readers, to weigh in.

Who won? Well, Darwin edges out Lincoln in our poll (and you’re welcome to vote even now). I guess my powers of persuasion won out. Or perhaps we stacked the deck by placing such a debate on a science blog.