Duke University scientists have conducted a new study that showed that people sleep an average of 7 hours a day. This is 2 times less than, for example, the sleep of pygmy lemurs, and some primates generally sleep 17 hours a day.
People sleep 7 hours a day, both in high-tech societies and in those that do not use high technology and adhere to natural light cycles.
It turns out that when people sleep, 25% of this time is occupied by REM sleep, during which they dream. The rest of the primates also dream, but the phase of REM sleep in them takes only 5%. The rest of the time they just doze. It is noted that humans can stay awake and act much longer, as they immediately plunge into REM sleep and spend much more time there than animals.
Experts were interested in how people manage to escape from the constant sleepiness that is inherent in other primates? According to the authors of the study, this happened when people climbed from the trees to the ground, and then this was facilitated by 3 reasons due to which the wakefulness cycle in human ancestors increased: the risk of death from predators, threats from intragroup conflicts, and the benefits that the individual received from the increased time of social interaction.
It is noteworthy that if a person has to do something interesting, he can easily sacrifice sleep, realizing that the next day his health will not be very good.
Scientists suggest that perhaps our ancestors did not sleep, but met with other people and passed on their wakeful genes faster. This means that entertainment and communication, and by no means fear, made people better dreamers, and therefore allowed them to become smarter and more active than other animals.