Insomnia, a defense mechanism

Adults fall asleep, often harder than the youngest. But, according to a new study by Duke University researchers, the difficulty of falling asleep is not just an overwhelming side-effect of aging but, on the contrary, could have evolving benefits. In this study, the researchers tracked the sleep habits of 33 men and women in perfect health from northern Tanzania who live a modern lifestyle. Their occupation of hunter-gatherers compels them to spend the day in nature and to return home in the evening. Because they do not have electricity, the group follows natural day and night patterns. While most members of the group slept from 10am in the evening until 7am, some slept from 11am in the evening until 8am and some from 8pm until 6am.

The most interesting part of the study is that during the 220 hours of observation, only in 18 minutes of the whole night all adults slept at the same time. From the evolutionist perspective, this is probably a survival mechanism - if a member of the group is awake at any time, it will be able to warn other members of the group about potential threats. .