What You Can Learn From Hunter-Gatherers’ Sleeping Patterns

Ed Yong in The Atlantic:

ScreenHunter_1445 Oct. 20 23.25Here’s the story that people like to tell about the way we sleep: Back in the day, we got more of it. Our eyes would shut when it got dark. We’d wake up for a few hours during the night instead of snoozing for a single long block. And we’d nap during the day.

Then—minor key!—modernity ruined everything. Our busy working lives put an end to afternoon naps, while lightbulbs, TV screens, and smartphones shortened our natural slumber and made it more continuous.

All of this is wrong, according to Jerome Siegel at the University of California, Los Angeles. Much like the Paleo diet, it’s based on unsubstantiated assumptions about how humans used to live.

Siegel’s team has shown that people who live traditional lifestyles in Namibia, Tanzania, and Bolivia don’t fit with any of these common notions about pre-industrial dozing. “People like to complain that modern life is ruining sleep, but they’re just saying: Kids today!” says Siegel. “It’s a perennial complaint but you need data to know if it’s true.”

Such data have been hard to come by because the devices that we use to measure and record sleep have only been invented in the last 50 years, and those that do so without disturbing the sleepers are just a decade old. So, there’s no baseline for how long people used to sleep before electric lights. Absent that baseline, Siegel’s team did the next best thing: They studied people who live traditional lifestyles, including Hadza and San hunter-gatherers from Tanzania and Nambia respectively, and Tsimane hunter-farmers from Bolivia.

More here.