Aping a mid-life crisis?

SMALL PRINTS:Do chimps and orang-utans experience mid-life crises? Possibly, suggests a study of more than 500 apes in captivity. The idea was to see whether the apes experience a low point in well-being in middle age, which has been broadly seen in studies of humans.

“In dozens of countries, and for a large range of well-being measures, including happiness and mental health, well-being is high in youth, falls to a nadir in midlife, and rises again in old age,” write the authors in Proceedings of the National Academy of Sciences.

So how do you know if an ape is feeling low? Zookeepers, researchers and volunteers who knew the apes rated the animals’ moods, pleasure socialising and whether they were achieving goals. And for both chimps and orang-utans, the age graph took on a similar U shape for well-being to the one seen in humans.

“Our results imply that human wellbeing’s curved shape is not uniquely human and that, although it may be partly explained by aspects of human life and society, its origins might lie partly in the biology we share with great apes,” states the study.

There could be other factors to consider though, according to Ian Robertson, professor of psychology at Trinity College Dublin, who was not involved in the research.

“Well-being depends a lot on your status, and chimpanzees and other higher apes have the equivalent in strong dominance hierarchies,” he says.

“I would have liked to see an analysis to see to what extent the age effect may be explained by an underlying dominance effect.

“For instance, maybe middle-aged apes are faced with more challenges to their ‘status’. But it is still a very interesting study.”