Apes go through mid-life crises.

Humans are members of the great ape family Hominidae, and the physical similarities between us and our primate cousins are clear. We have the same arrangement of internal organs and roughly the same number of bones, we lack external tails, and we even get the same diseases. So it only makes sense that we share some psychological similarities as well. A 2012 study published in the Proceedings of the National Academy of Sciences reported that chimpanzees and orangutans experienced a midlife crisis similar to that of humans.

The study analyzed the behavior of 508 chimps and orangutans in captivity at zoos in five different countries, and found that these animals’ well-being hits its nadir around their mid-20s or early 30s (the equivalent of middle age for chimps and orangutans). Of course, scientists couldn’t directly ask the chimpanzees how they felt, but instead relied on zookeeper questionnaires to assess the animals’ overall mood, level of joy in social situations, and how successful they were in achieving particular goals. Although the dataset is subjective, its sheer size highlights an overall trend that’s remarkably human, since we also tend to experience a dip in happiness and well-being around midlife. It’s just another trait that entwines us with our primate brethren.