“Primatologists have seen this many times in the field: Say a male is fighting with another male. The females largely ignore the conflict, so long as it doesn’t bother them or their children. But then one of the combatants goes off and picks up a baby, who blithely clings to his chest hair or his back. Then he goes over to the male he was having the fight with. If the baby likes the male it’s clinging to, the kid will scream at his opponent if he acts aggressively. So the other male either backs off or is mobbed by friends of the mother, spurred on by the baby’s cries. It’s so effective, in fact, that some males simply carry a baby around as a kind of adorable bodyguard, preventing fights before they start.”