Yeah i sometimes wonder about this in the context of our evolutionary history. Having some people around who naturally stay up late to tend the fire and keep a look out seems advantageous. I suppose teenagers can fill this role, but their numbers fluctuate.

This is why I continue to seek out and work evening shifts. 3am-10:30am is just about exactly what my body wants to do naturally. Shifts that start at noon and get out after dark are perfect; once I got that synergy, I stopped feeling tired all the time.

That said, sleep is a complicated, personal thing, and everyone's a little different. You should do what feels right to your body, because it might be very different from what works for my own.