Science Update - Lizard Toes and Dance

The Naked Scientists spoke to Chelsea Wald and Bob Hirshon from AAAS, the science society
01 October 2006

Interview with 

Chelsea Wald and Bob Hirshon from AAAS, the science society


Bob - This week on Science Update, we'll learn why top engineers are working long hours studying lizard toes. But first, if fighting and making up with your significant other sometimes feels like a highly choreographed dance, you'll probably identify with this report from Chelsea.

Chelsea - At least one killer whale couple has a way to kiss and make up, and others may, too. That's according to animal behaviourist Michael Noonan of Canisuis College and his student Cerrene Giordano. They studied a year's worth of video tape of one pair of captive killer whales and found eight incidents of aggression, in which the female chasing the male. After a cooling-off period, Noonan says the killer whales then began to swim along side - by-side, in a behaviour called echelon swimming.

Michael - And they don't just swim along side-by-side, their tail strokes stroke in synchrony, so they're swimming in what almost looks like a dance. It's beautiful to watch.

Chelsea - He says echelon swimming is a common behaviour among other captive and wild killer whales, and scientists believe it reinforces bonds between animals. He says only more research can show whether other whales use echelon swimming to make up after quarrels, but it's intriguing that the animals seem to have the capacity for reconciliation at all.

Michael - It's hard to name something that's more valuable in human behaviour than peacemaking. So it's particularly exciting to see suggestions of peacemaking in killer whales.

Chelsea - He adds that it's one of only a few known peacemaking behaviours outside the world of primates.

Bob - Thanks, Chelsea. In the states, a cartoon gecko is a well-known spokes animal for a car insurance company. But selling insurance isn't their only trick. Geckos are also marvels of engineering. That's because the surface of their toes is packed with millions of tiny, spatula - shaped hairs. These hairs create enough friction to allow the gecko to scamper effortlessly up smooth walls, and enough adhesion to hang its entire body weight from a single toe - and yet the hairs can release their grip just as quickly and easily as they stick. Electrical engineer and computer scientist Ron Fearing of the University of California at Berkeley is leading an effort to create artificial microfibres that act like gecko feet. Their current prototype packs 250 million hairs per square inch.

Ron - These hairs make intimate contact with glass. And they don't slip, it's very high friction. But it doesn't quite work like the gecko because if you try to pull it off, it pulls off really, really easily, actually much easier than the gecko pulls off.

Bob - He says their current material could provide good traction for tires and shoes. But the technology could also lead to other applications, from pain-free adhesive bandages to wall-climbing robots.

Chelsea - Thanks, Bob. That's all for this week. Next week we'll discuss some more cutting edge technologies-one that should prevent train derailments and another that should speed up biohazard detection. Until then, I'm Chelsea Wald.

Bob - And I'm Bob Hirshon, for AAAS, The Science Society. Back to you, Naked Scientists.


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