Sleeping Less In Old Age May Be Adaptation To Survive In Wild...

This is the best tl;dr I could make, original reduced by 67%. (I'm a bot)

Fifty years ago, psychologist Frederick Snyder proposed that animals who live in groups stay vigilant during sleep, by having some stay awake while others rest.

Samson recruited 33 adults from two nearby groups of 22 huts and asked them to wear motion-sensors on their wrists to monitor sleep, for 20 days.

"It turned out that it was extremely rare for there to be synchronous sleep," says Samson, now at Duke University in Durham, North Carolina.

At least one person was either awake, or sleeping lightly and could easily be roused, for 99.8 per cent of the sleep periods sampled, and on average eight of the adults were awake at any given time.

Further analysis revealed that this variation in sleep timing could be almost entirely accounted for by the mixture of ages in the group.

This study suggests there may be another advantage: "We're calling it the 'poorly sleeping grandparent' hypothesis," says Samson.

Summary Source | FAQ | Feedback | Top keywords: sleep^#1 group^#2 Samson^#3 adults^#4 people^#5

Post found in /r/science.

NOTICE: This thread is for discussing the submission topic. Please do not discuss the concept of the autotldr bot here.