Female Baboons Are So Clever!
Silk saw a correlation between sociability and longevity. She divided the baboons into three groups, and found that the least friendly lived 7 to 18 years, while the friendliest group lived from 10 years on (they were still kicking when the study ended). They also found that those baboons who formed stable, enduring bonds were more likely to have long lives than those with flightier friendship habits.
It’s tempting to look for parallels between baboons and humans, and indeed, the researchers engage in a little speculation.
Such findings in a nonhuman primate, the authors write, “suggest that the human motivation to form close and enduring bonds has a long evolutionary history.” … They note that previous research in humans has shown that socially isolated people suffer more from high blood pressure and sleep disorders and have longer wound-healing times.
But back in the animal world, it’s still not clear how these stable friendships could make baboons live longer. It’s possible, they say, that more friendly grooming could mean fewer parasites, or more social interactions could mean more eyes to watch for predators.
“It all depends on what causes the death of female baboons, which is hard to determine because there’s seldom a single cause,” comments
In this baboon species, males miss out on friendship and its possible benefits. It seems that chacma males never groom each other, and only groom women before sex.