Whales napping . . . Ars Technica

 

Might sign off for the day now with a nap     (you’re going to sleep now aren’t you? - ED)

Sperm whales like to nap under the water and away from the waves. They seem to do this in a vertical, head-up orientation. That makes sense, given that their enormous heads, which take up a third of their bodies, are full of oil, wax, and air–all buoyant materials. What’s less obvious is how the whales maintain their depth while sleeping. (Image credit: S. Granzotto; research credit: N. Freymond et al.; via Ars Technica)