Humans get by on sleeping less compared to animals. Researchers from Duke University claim that while humans’ closest animal relatives sleep longer, human sleep is more efficient.

On average, people get seven hours of sleep at night, while other primate species, including lemurs and macaques, need 14 to 17 hours. People can survive on this short amount of sleep because human sleep is more efficient, the team adds. In other words, more time is spent on the deeper stages of sleep and less on the light stages.

Experts searched for previous scientific studies and then compiled a database of sleeping patterns of mammals that included 21 species of primates and people. The team remarked that rapid eye movement (REM) comprises 25 per cent of the human’s overall sleep.

However, according to the study, primates’ REM, such as the mouse lemurs, mongoose lemurs and the African green monkey, only takes a smaller portion, barely climbing up to five per cent of their overall sleep.

The researchers note that constant access to artificial light from streetlamps or computer screens does not cause these results. They claimed that even people from Tanzania, Namibia and Bolivia, where electricity is unavailable, sleep less than those with access to technology.

They described sleep as unique, suggesting that humans replaced sleep quantity with sleep quality long before the advent of high-tech gadgets. If artificial light and other aspects of modern life were at fault for shortening sleep, researchers said that hunter-gather societies would sleep more without access to electricity.

Study co-author David Samson said in a press release that early humans started sleeping near the fire to keep warm and drive off predators. He said these habits could have allowed the ancestors to get most out of their sleep in the shortest time possible. Additionally, shorter sleep time provided time to do other things like learning new skills and socialisation. Meanwhile, deeper sleep caused them to sharpen their memory and boost brainpower, cementing those skills learned during the extra time.