Anyone who has teenage children, but also anyone who has been a teenager, knows that once puberty is reached, life suddenly becomes more interesting but also more dangerous. There are many studies (this one, for example) that explain the correlation between adolescence and taking risks that, as long as you are a child, you don’t even dream of approaching.
Well, this tendency to do inadvisable things is not a human exclusive: as explained by a study published in iSciencea team from the University of Michigan found that adolescent chimpanzees also go through a “high-risk” life stage. The reason? Surprisingly, hormones have nothing to do with it.
The risks of life in the jungle. The team that conducted the study deals with locomotion in chimpanzees: these primates lead a very dangerous life, given that they live in trees and have to move from branch to branch, often with tens of meters of fall beneath them. Obviously, not all chimpanzee arboreal movements are the same: some are more dangerous, others safer, as the team was able to observe in a population of Ngogo, in Uganda’s Kibale National Park.
The falls. Years of observations have revealed that chimpanzees typically jump from branch to branch to navigate the forest. In some cases, however, to do so they have to cover the long distances that separate two trees, with the risk of falling down. In other cases they do something even more dangerous: they let go of the branch they are hanging from to grab one below, or to fall directly to the ground. A risky operation that doesn’t always end well: falls are one of the main causes of death among chimpanzees.
Age and prudence. The Michigan scientists then tried to understand whether there is a link between the risk rate of a jump and the age of the chimpanzees. By observing a hundred of them, aged between 2 and 65, they discovered that the most dangerous period for these primates, the one in which they make the riskiest leaps, is between late childhood (2-5 years) and the end of adolescence (up to 15). As they mature, chimpanzees increasingly reduce dangerous jumps, eventually eliminating them altogether.
Parental controls. According to the authors of the study, the motivation is not physiological as one might think: it is not the hormones of adolescence that stimulate chimpanzees to take risks.
It is rather the end of the period of parental control: chimpanzees spend the first two years of life attached to their mothers, and when they become independent they also begin to take risks. The dangers of adolescence, therefore, are part of a natural process of emancipation from parents – very similar, according to the authors, to what we humans go through.
