Snooze patterns vary across cultures, opening eyes to evolution of sleep

Amount, timing of sleep is less important for health than sticking to routine

person napping

SLEEP SUPPLEMENT  A Hadza forager in East Africa takes time out to catch a few z’s during the day. Naps enable the Hadza to catch up with their sleep after dozing an average of about 6.5 hours at night, researchers say. Evolution has reduced the quantity and boosted the quality of human sleep relative to other primates, they hold.

D. Samson

Hunter-gatherers and farming villagers who live in worlds without lightbulbs or thermostats sleep slightly less at night than smartphone-toting city slickers, researchers say.