Humans didn’t really start consistently sleeping 8 solid hours in one go until the industrial revolution or so.
That’s based on some really tendentious readings of a few people’s accounts of waking up at night in the Middle Ages. Some people probably did that, especially at latitudes where the nights are 18 hours long in winter, but generalizing that to something that happened everywhere and at all times of year prior to the industrial revolution is a massive stretch.
Not just the second sleep theory, though I’d argue it isn’t exactly just a “few peoples accounts”, but stuff like siesta and naps in general.
The point isn’t to say everyone slept the exact same biphasic sleep before but that after the industrial revolution the shift has been for everyone to transition to the “8-hours at night in one go at exactly the same time” method, which doesn’t suit everyone and isn’t exactly natural. Before artificial lights and clocks people slept with way more irregularity as there wasn’t any strict time schedule to follow, and people waking up during the night or not getting enough sleep at one go wasn’t really such an issue.
Not to mention that your sleep would have to follow the seasons and the sun way more.
That’s based on some really tendentious readings of a few people’s accounts of waking up at night in the Middle Ages. Some people probably did that, especially at latitudes where the nights are 18 hours long in winter, but generalizing that to something that happened everywhere and at all times of year prior to the industrial revolution is a massive stretch.
Not just the second sleep theory, though I’d argue it isn’t exactly just a “few peoples accounts”, but stuff like siesta and naps in general.
The point isn’t to say everyone slept the exact same biphasic sleep before but that after the industrial revolution the shift has been for everyone to transition to the “8-hours at night in one go at exactly the same time” method, which doesn’t suit everyone and isn’t exactly natural. Before artificial lights and clocks people slept with way more irregularity as there wasn’t any strict time schedule to follow, and people waking up during the night or not getting enough sleep at one go wasn’t really such an issue.
Not to mention that your sleep would have to follow the seasons and the sun way more.