Goodnight. Sleep Clean.

Sleep seems like a perfectly fine waste of time. Why would our bodies evolve to spend close to one-third of our lives completely out of it, when we could instead be doing something useful or exciting? Something that would, as an added bonus, be less likely to get us killed back when we were sleeping on the savannah?

Sleep is such a dangerous thing to do, when you're out in the wild, Maiken Nedergaard, a Danish biologist who has been leading research into sleep function at the CTN, told me. It has to have a basic evolutional function. Otherwise it would have been eliminated.

To read more please see the NY Times article.