The penguin wave

Emperor penguins are known to form tight huddles to stay warm in Antarctica's bitterly cold conditions. However, research published last week shows that the penguins move every 30 to 60 seconds in coordinated periodic waves in these huddles. This allows every penguin a chance to move from the colder outer region of the huddle into the warmer inner region. Isn't that cool?

More on the penguin waves here.