Many older people are looking for a doctor because they are worried that they are not getting enough sleep. But this may be part of the evolutionary past, not actual sleep disturbance.
Scientists at Duke University in the United States have discovered the reason that humans are suffering from insomnia as they age as they study the hunter-gathering tribe.
The study targeted Chinese tribes in northern Tanzania and observed 33 tribal peoples for three weeks.
During the three-week period, they found that the entire tribe spent only 18 minutes to sleep. They had a lifestyle similar to that of agriculture, hunting, and gathering.
They also conducted surveillance activities to protect the tribe from natural enemies, and one of the tribes stood guard throughout the night to defend the tribe.
In other words, someone else is awake. This has led scientists to conclude that modern human insomnia is a way of protecting us from habits and carnivores that have been rooting us for thousands of years.
Dr David Samson, co-author of the study, said, "There was a claim that living with grandparents for a while was beneficial. This study has revealed that one of the reasons for this is nighttime sleep monitoring. "
During the day, men and women are scattered and find meat, nuts and berries in the forests around Lake Ayassee.
When it gets dark, all tribesmen return to the village to sleep. They sleep near a fire or sleep in a hut made of grass and branches.
"They sleep on the floor and their habitats do not have synthetic lighting or controlled climate," said Alisa Cretten, an associate professor of anthropology at the University of Nevada, Las Vegas. They have a life style that is most similar to the human past of hunting and gathering, so we can explain an important part of human evolution. "
The researchers previously found similar results in mice and birds, but this is the first time human studies have been done. This has led scientists to discover why humans are sleeping for a shorter period of time as they get older.
Charlie Knowne, a professor of evolutionary anthropology at Duke University, says, "Many older people look for doctors because they get up early and can not sleep at night. But perhaps there is nothing wrong with them. Some of the medical problems we have today are not obstacles, but relics of the evolutionary past. "
