Among other things that help us surpass primates, humans evolved to be the best sleepers by sacrificing quantity for the sake of quality. This means that we have evolved to rest for just the right amount of time. Our sleep is efficient for the purpose of minimizing the amount of time wasted while resting.
Average primate sleeps between 14 to 17 hours per night
Researchers from Duke University analyzed massive amounts of data on sleeping patterns from numerous mammals, including 21 species of primates. This ranged from lemurs to chimpanzees, and, naturally, humans. They found that most primates require between 14 to 17 hours of sleep per night. It’s quite a substantial amount even for the laziest of us. Even our closest relatives, the chimps, need around 11.5 hours of slumber.
As most know, humans between the ages of 18 and 64 years old require between 7 to 9 hours of sleep per night. That’s the healthy range given by numerous studies, with both less and more being deemed as ‘bad for you’. According to co-author of the study, David Samson, this is because humans have evolved to sleep less, but sleep better.
Humans spend more time in REM
The team of scientists found that the average human spends about 25% of their sleep in the deep stage called rapid eye movement (REM). This is compared to most other primates, who spend as little as 5% in REM. This makes our behavior regarding sleep unique. We sleep less because we sleep more efficiently. This is the mark of evolution though, not a consequence of technology.
According to Samson, our penchant for efficient sleep has nothing to do with electricity or artificial lights. Our patterns have not shortened due to the invention of television, smartphones, or the unnatural lights that fill our homes and our streets. These changes were made far, far earlier. Stress was another factor that was instantly eliminated from the equation.
If electricity or artificial lights were to be blamed, that would mean that the population in under developed regions without electricity would have to sleep more. However, that is not the case. Even when observing societies in Tanzania, Bolivia, or Namibia, where electricity infamously lacks, the results were the same. The 24/7 hour access to computers, smartphones, or digital entertainment has little to do with this unique trait.
Instead, scientists believe this started to occur early, when humans climbed down from their “tree beds” and starting sleeping on the ground. With the invention of fire and other protective measures, they could ward off predators easier. That meant that time sleeping was more efficient, as they rested better and without the fear of becoming prey.
The transition to sleeping on the ground was the main factor that influenced our sleeping efficiency today.
Image source: catster.com