Chimpanzees and orangutans in the midlife crisis?
Scientists have identified similar fluctuations in the state of mind over the course of their lives as they are observed in humans. In adolescence, the monkeys experience an exhilaration of well-being that gradually decreases until the middle of life and then increases again. The scientists here speak of a U-curve of well-being over the course of life.
The international team of researchers led by Andrew Oswald from the University of Warwick (England) and Alexander Weiss from the University of Edinburgh (Scotland) have examined the course of wellbeing in the course of life in chimpanzees and orangutans in order to find possible parallels to that of humans to discover the well-known phenomenon of the midlife crisis. Previous theories "emphasize sociological and economic factors" as the cause of the crisis in the middle years of life, but the researchers have now been able to prove that there is obviously an evolutionary disposition for this. The modern, youth-oriented lifestyle, everyday stress, debts or past separations or divorces have a significantly smaller impact on the mid-life crisis than previously thought. The researchers published their results in the journal "Proceedings of the National Academy of Sciences" (PNAS).
Well-being of 500 great apes examined The well-being that is decreasing towards the middle of life causes considerable problems for many people with aging. You can now comfort yourself with the idea that the predisposition to this midlife crisis is obviously evolutionary and has already been put into their cradle. Because great apes also show a comparable decline in well-being in middle age. The researchers led by Andrew Oswald and Alex Weiss examined the well-being of 155 chimpanzees from a Japanese zoo, 181 chimpanzees from zoos in the United States and Australia, and 172 orangutans from zoos in the United States, Canada, Australia, and Singapore . The mood of the 508 great apes was documented by the zookeepers, volunteers and scientists, who were very familiar with the individual animals. The condition of the animals was described with factors that characterize the mood in humans.
Monkeys and humans show low mood at mid-life In all samples, the researchers found a U-shaped course of well-being in the life of the monkeys. The well-being of the animals reached its lowest point at an age between 28 and 35 years, which is "comparable to the human minimum of well-being between the ages of around 45 and 50 years", the scientists report in the journal "PNAS".
Evolutionary midlife crisis? According to the scientists, the evolutionary biological approach has so far been neglected in explaining the midlife crisis. "Although great apes have a close genetic relationship with humans and share many behavioral traits with us, including culture and tools," a study comparable to the current one has not yet been carried out. The researchers led by Andrew Oswald and Alexander Weiss had hoped that due to the close relationship between great apes and humans, similarities in the degree of their well-being can be seen across life spans. But "you never know what will come out of studies", explained Weiss and was pleased "that the results correspond to those from many other areas." Your "findings have an impact on scientific and social-scientific theories, and can help To identify ways to improve the wellbeing of humans and monkeys, ”the scientists concluded. (fp)
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