Is war central to human nature? Chimps can’t tell us everything
For decades, the 200 Ngogo chimpanzees in Kibale National Park, Uganda, lived what seemed a calm and normal existence. Males and females hunted together, groomed each other and went on patrols through the forest. Within this large group, cliques were formed but they often intermingled and share territory, like something from a simian Pixar film. But in June 2015, something happened and the group split in two. Then, the violence started. The scientists watching this schism aren’t sure why things became so belligerent. It started with members from one group chasing the other and prolonged periods of avoidance. As polarization increased, so did the aggression, eventually becoming lethal. Over the years, at least six adult males were targeted, followed by at least 17 infants that were killed. What was surprising about these killings isn’t that chimpanzees are some sort of primate pacifists and these ones suddenly went rogue. Indeed, chimps have been documented killing each other before, but usually one-off in events rather than in conflict between distinct groups that were formerly united. What made …



