STATES CHRONICLE – Sleep is without a doubt one of the most satisfying activities a human can partake in. It’s not only helpful for the body, but also for the mind, and it lets you take a short time off from your daily struggles. And apparently, the thing about it for us human beings is that it’s the same as most other things we get involved in: quality over quantity – or why we sleep less than other animals.
Researchers from Duke University were interested in why humans, as arguably the most advanced animals on Earth (mice, dolphins, I’m looking at you), also happen to sleep the least.
The scientists behind the research performed studies and read literature on hundreds of species of mammals, and even 21 primates, in order to create a database of sleeping patterns.
They then established each species’ position in the primate family tree.
It resulted that humans are exceptionally short sleepers, with an average of 7 hours a night, as opposed to other species like lemurs, macaques and baboons, which sleep up to 17 hours a night.
So, naturally, they had to find out why.
As it turns out, our sleep is a lot more efficient than that of other primates, thus letting us get away with fewer hours of shut eye.
REM sleep is arguably the most important stage of sleep, as that is when we are the most relaxed and when dreaming occurs. It is also only present in mammals.
Compared to other mammals, we spend a lot less time in lighter sleep stages, and a lot more in the REM stage. For example, some African monkeys spend barely up to 5% of their sleep time in REM, while we spend up to 25% in the dream state.
The researchers are theorizing that the reason behind this is due to our steady abandonment of our tree branch sleeping arrangements, and our tendency as a species to start sleeping in groups.
Since we became a community, we started losing the need for extra sleep, our patterns focusing on the quality of our sleep instead of on its quantity.
The researchers also studied 3 groups of hunter-gatherers from Bolivia, Namibia, and Tanzania in order to verify the myth that we started to sleep less because of the sudden appearance of artificial lighting in our lives, but they also turned out to have very similar sleeping patterns, thus officially busting that myth.
Image source: Wikimedia