Why Humans Slept in Piles for 300,000 Years

For almost all of human history, nobody slept alone, and nobody slept eight hours straight. They slept in groups, in halves, with someone always awake in the dark. This is what sleep looked like before artificial light — from the oldest bed ever found, to the hour our ancestors spent awake in the middle of the night, to the reason you wake at three in the morning and think something is wrong with you. 0:00 You slept alone last night 0:28 Nobody chose this 1:03 The oldest bed ever found 2:34 A night in camp 4:00 Somebody was always awake 5:36 First sleep and second sleep 7:46 What the dark hour was for 8:49 The problem with this story 10:13 What ended it 11:45 What it cost Sources and further reading: Wadley et al. (2011), Middle Stone Age Bedding Construction at Sibudu, Science Samson et al. (2017), Chronotype variation drives night-time sentinel-like behaviour in hunter-gatherers, Proc. R. Soc. B Ekirch, A.R. (2005), At Day's Close: Night in Times Past Wehr, T.A. (1992), In short photoperiods, human sleep is biphasic, Journal of Sleep Research Wiessner, P. (2014), Embers of society: firelight talk among the Ju/'hoansi Bushmen, PNAS If you have ongoing trouble sleeping, that's worth taking to a doctor rather than a YouTube video ;)