Study Suggests Chimps May Experience Mid-Life Blues

Mid-life crisis does not only hit humans but Chimps too. Human beings susceptible to mid-life crisis witness inconsistency in their behavior. It turns out that chimps are more like us and witness some emotional discontent at life's midpoint.

A new study reveals that Chimpanzees and orangutans can experience a mid-life crisis just like humans. This study tests the theory that we may share the biology of our behavior with the great apes.

This study was led by a team of international researchers including economist Andrew Oswald, a professor from the University of Warwick and psychologist Dr Alex Weiss from the University of Edinburgh.

The team said that chimpanzees and orangutans follow a U shape curve of life patterns similar to humans: There is a high in youth, a fall in middle age and there is a rise again into old age.

"What we are testing is whether the U-shaped curve can describe the association between age and well-being in non-human primates as it does in humans," psychologist and lead author Dr Alexander Weiss of the University of Edinburgh told BBC Nature.

For this the researchers studied nearly 508 great apes that were housed in zoos and sanctuaries in the United States, Japan, Canada, Australia and Singapore.

The teams assessed the apes' well being from the keepers, volunteers, researchers and caretakers who knew the apes well. Their happiness was scored based on a series of measures adapted from human well-being measures.

 Professor Oswald said: "We hoped to understand a famous scientific puzzle: why does human happiness follow an approximate U-shape through life? We ended up showing that it cannot be because of mortgages, marital breakup, mobile phones, or any of the other paraphernalia of modern life. Apes also have a pronounced midlife low, and they have none of those."

Dr Weiss said: "Based on all of the other behavioral and developmental similarities between humans, chimpanzees, and orangutans, we predicted that there would be similarities when looking at happiness over the lifespan, too. However, one never knows how these things will turn out, so it's wonderful when they are consistent with findings from so many other areas."

Their findings do not rule out the influence of socio-economic and cultural forces as part of the reasons behind the U shaped pattern of well-being in humans.

Naturally, the findings have attracted skeptics.

The study is published in the Proceedings of the National Academy of Sciences.