On: Sleep is essential – researchers are trying to work out why

[Noumenon72]

I have spent months at a time getting 7-8 (amid years of 5-6). I never notice any difference and am actually surprised my body can do 7-8 to no purpose.

[bpodgursky → Noumenon72]

From the perspective of evolution there's a purpose... burn fewer calories in the dark when there's nothing else to do.

The question is whether it still matters in the modern era.