Men who cope with competition like bonobos – that is, passively – also show changes in cortisol levels, past research shows. To these guys, competition is more of a stressor than a status-determining event. Other studies have shown some men respond to competition more like chimpanzees and experience changes in testosterone levels.

But the jury is still out on whether the same guy would experience different hormone changes depending on the situation.

“It’s actually an area for future research whether the same man, presented with different events, would react differently, being chimpanzee-like in one situation and bonobo-like in another, or show a similar profile across situations, being always chimpanzee-like, for example,” Wobber said.

Something unique about human males is that after competition they experience an increase in testosterone if they win or a decrease if they lose, accounting for giddy or depressed sports fans following a win or loss. This post-competition change wasn’t seen in the apes.