'You may not look forward to sleeping less as you get older. But maybe it wouldn?t seem as bad if you knew it once played an important role in human survival.
A new study, published Tuesday in Proceedings of the Royal Society B, suggests that the way sleep patterns change with age may be an evolutionary adaptation that helped our ancestors survive the night by ensuring one person in a community was awake at all times. The researchers called this phenomenon the ?poorly sleeping grandparent hypothesis,? suggesting that an older member of a community who woke before dawn might have been crucial to spotting the threat of a hungry predator while younger people were still asleep. It may explain why people slept in mixed-age groups through much of human history.
?We may be looking at just another reason why grandparents were critical in human evolution,? said Alyssa Crittenden, an author of the study and an associate professor of anthropology at the University of Nevada, Las Vegas.
Researchers analyzed the sleep patterns of a society of hunter-gatherers in Tanzania called the Hadza. Thirty-three members of the Hadza community wore small watchlike tracking devices on their wrists for 20 days.'>>>
https://www.nytimes.com/2017/07/13/s...volution.html?
Reply With Quote