What Did Ancient Humans Actually Do When They Couldn't Sleep?

It's 3 a.m., you're wide awake, and your alarm is four hours away. What if nothing is actually wrong with you? In this animated explainer we rewind time to see how people slept before electric light. Historical records describe a "first sleep" and a "second sleep" with a quiet waking hour in between. A lab experiment with long, dark nights saw sleep split in two, and a study of Hadza hunter-gatherers found that the whole group was almost never asleep at the same moment. We also look at why worrying about being awake can keep you up longer. Do you ever wake up in the middle of the night? What do you do when it happens? Tell us in the comments. Sources: A. Roger Ekirch (2001). "Sleep We Have Lost: Pre-Industrial Slumber in the British Isles." The American Historical Review, 106(2), 343-386. Thomas A. Wehr (1992). "In short photoperiods, human sleep is biphasic." Journal of Sleep Research, 1(2), 103-107. David R. Samson, Alyssa N. Crittenden, Ibrahim A. Mabulla, Audax Z. P. Mabulla & Charles L. Nunn (2017). "Chronotype variation drives night-time sentinel-like behaviour in hunter-gatherers." Proceedings of the Royal Society B, 284(1858), 20170967. Gandhi Yetish et al. (2015). "Natural sleep and its seasonal variations in three pre-industrial societies." Current Biology, 25(21), 2862-2868. #sleep #history #ancienthumans #science #explained