Here’s How Humans Evolved To Be Really Efficient Sleepers

Humans have evolved the ultimate life-hack: we get better sleep in less time than most of the animal kingdom.

We not only get significantly less shut-eye than our animal relatives, we’re also more efficient at it because we spend more time in deep than light sleep, according to a new study by researchers at Duke University in Durham, North Carolina.

Less sleep may have allowed humans to devote time to learning skills and forging social bonds, whereas deeper sleep may be critical for sharpening and enhancing cognitive abilities.

“Humans are a unique species and given the intuitive concept that our sleep is linked to how we think, feel and behave, I was less surprised and more excited about the findings that support the idea that sleep has played a part in the evolution of our species,” Dr. David Samson, an evolutionary biologist at the university and a co-author of the study, told The Huffington Post.

The researchers compiled a database of sleep patterns among hundreds of mammals, including humans and 21 other primate species, such as chimpanzees and baboons. Then, the researchers conducted a statistical analysis of their data and found that humans are the shortest sleepers of all the primates, snoozing for an average of about seven hours a night. Most primates get between 14 and 17 hours of shut-eye.

The researchers concluded that humans are able to rest less because they get more rapid-eye-movement, or REM, sleep per hour than do other species. About 25 percent of our time sleeping is spent in this deeper, more relaxed mental state, compared to only 5 percent in other primates.

Scientists aren’t sure why humans evolved to make the most of sleep. One hypothesis is that the advent of artificial light “tricked” our biological clocks into sleeping less, but —> Read More