Rare Split in Uganda Chimp Community Kills 24

Researchers have documented a rare and violent split within the world's largest known community of wild chimpanzees in Uganda's Kibale National Park, where former allies turned lethal enemies, killing at least two dozen individuals over several years.

The Ngogo chimpanzee community, which peaked at more than 200 members, began fracturing in 2015 after two decades of relative cohesion. By 2018, the group had permanently divided into two distinct factions, known as the Western and Central clusters, each claiming separate territories. Members of the smaller Western group launched coordinated attacks on the Central group, resulting in the deaths of seven adult males and 17 infants between 2018 and 2024, according to a study published Thursday in the journal Science. An additional 14 adult or adolescent Central males disappeared during that period without signs of illness, suggesting further unreported violence. Researchers have observed at least two more attacks since 2024.

The findings come from the Ngogo Chimpanzee Project, a long-term effort led by anthropologists Aaron Sandel of the University of Texas at Austin and John Mitani of the University of Michigan, involving over 30...