[genocidicbunny]

I am not sure exactly how widespread it is/was, but as I understand that biphasic sleep was pretty common before artificial light and the rise of civilization. With the recent dropping of external pressure to get up as early or go to bed as late, it's not terribly surprising that some people would gravitate towards that; Kids even more so -- their sleep patterns are not quite as well established.

It's pretty likely they're not actually sleeping all those 13 hours. If they were, I would be suspicious of some other underlying cause.

[the_only_law]

So I had messed up my sleep really bad this year, to the point where I was ending up not sleeping for days or sleeping the whole day (on weekends for example) and have been slowly trying to bring myself to a more sane baseline. At one point a sort of bi-phasic schedule where I would initially sleep in the mid-late afternoon and then again either very late at night or early morning. If i had more flexibility in my schedule, I'm convicned it wouldn't be that bad.