What's the evolutionary advantage of

sleep?
I can understand big predators requiring sleep to conserve energy.
But why do humans need sleep? A group of humans who needed no or much less sleep could have easily outcompeted us.

>>17
Describe to me the biochemical pathways that require or lead to sleeping then.  Are these pathways not included in the DNA?  If they are, then sleep is necessarily encoded in the DNA (just like eating and drinking).  I'm pretty sure trees/bacteria don't sleep.

>>18
Did you even read?  Choking?  Nitrogen bubbles leading to pulmonary embolism?