polyphasic sleep

[Witty]

Originally Posted by oats

is there any evidence that we used to sleep in polyphasic patterns? This is new info to me, but I do know that biologically we still adhere to a 24 hour night-day rhythm, even in the absence of physical stimuli. So what I'm saying is, I'm very doubtful that humans ever slept like this, unless consciously done so.

That being said, I also know that the first settling europeans had what they called "second sleep" during the winter, where they would wake up at one point in the night for a few hours, do things by candlelight, then go back to bed. This was a direct result of shorter days, however, so it was still a response to circadian rhythm.

I would imagine that the very earliest modern humans already had that instinct or whatever it is to sleep at night, as humans are basically ineffective in the dark anyway, but we also would have been in the food chain back then, and when you're in the food chain you sleep when you can, not when you want.

So yeah, it would have had to have been a concsious decision because it worked for the circumstance. It is in our nature to sleep at night, and I am pretty sure it always has been.