Taking turns seems like an easy enough concept (though lets be honest, it’s not.) But for the thousands of Emperor Penguins (Aptenodytes forsteri) that call Antarctica’s vast ice sheets home, taking turns to stay warm is a highly complex affair.
A team of researchers, led in part by scientists from the Department of Physics at the University of Erlangen-Nuremberg in Germany, set up a time lapse camera to track the movements of a pack of penguins near the Neumayer Antarctic Research Station. When sped up, the video showed subtle movements that hadn’t been noticed through observation of the pack with the naked eye. The penguins, in their own way, do a version of the wave with coordinated movements that radiate through the group.
In the study, the researchers explain that when penguins huddle they are typically packed so tightly together, individual movements become nearly impossible. Animals on the inside of the huddle might be warm and toasty, but for those on the periphery, simply staying close to the group isn’t enough to drive away the Arctic chill. That is why the pack has to reorganize, moving as a unit rather than as individuals to allow a constant rotation of penguins through the huddle.
Analysis of the time lapse video showed that every 30-60 seconds all penguins in the huddle made small steps that traveled like a wave through the group. Each penguin step measures a mere 5-10 centimeters, so for the movements to cause a large-scale shuffle of the huddle takes considerable time.
The researchers hope to explore what triggers the penguins to move in this manner. It is unclear if there is an individual, or a few individuals, who signal the group to move, or if each penguins follows a group hierarchy on its own to determine when to move. However the wave gets started, is seems to work well for the penguins many of which are carrying and protecting eggs while fasting.
One thing is sure, the finesse and calm with which these penguins take turns doing the wave is far more orderly than any group of humans you’ll see doing the signature move to cheer on the home team.
(via Scientific American)
Published: Jun 2, 2011 01:57 pm