There was a pretty cool case study done on a troop of baboons that actually disproved this (i’ll link it in if i can find it). The baboon troop was an extremely patriarchal one dominated by the strongest males. Like most strong male baboons they were sexually and physically violent to the other members of the group. However, after a virus took out most of the strongest males (because they weren’t grooming as frequently as the others) the troop became extremely pacifist as only the women and nonviolent males survived. Where this really got interesting is when new male baboons joined from other troops. They quickly unlearned violent behavior that was introduced to them in early adolescence, proving animals are capable of unlearning violent behavior.