Aaron Sandel can pinpoint when it all started. The codirector of the Ngogo Chimpanzee Project had been observing a group of ...

Outbreaks of violence between chimpanzees have sparked fierce debate online about the origins of war in humans ...

For years, two sets of chimpanzees lived as one in Uganda’s Kibale National Park — grooming, interacting and patrolling their territory in a cohesive community. Then suddenly, one set charged the ...

A once harmonious group of wild chimpanzees has split into two, leading to intractable conflict and escalating violence. Researchers say the rift suggests that human wars are a deeply rooted part of ...