Scientists Record a "Civil War" Between Chimpanzees in Uganda (3 photos)
In Uganda's Kibale National Park, scientists have recorded an extremely rare phenomenon: the largest known chimpanzee community split into two warring groups that engaged in deadly conflict. 
A study published in the journal Science describes how a group of approximately 200 chimpanzees experienced a de facto "civil war." Scientists estimate that such splits occur on average once every 500 years.
For many years, the chimpanzees lived as a single community, despite being divided into two clusters—Central and Western. The animals interacted freely, moved, and mated. However, in 2015, the situation changed dramatically.
During one observation, the Western group unexpectedly retreated upon encountering the Central group, and was then pursued by it—such behavior had never been recorded before. This episode marked the beginning of a rift. 
By 2017, the groups had completely separated their territories and began guarding their boundaries. By 2018, the conflict had escalated into violence. From 2018 to 2024, researchers recorded killings: members of the Western group killed at least seven males and 17 cubs from the Central group. Another 14 adult or young males went missing and were likely also victims of attacks.
Scientists believe the split was caused by the breakdown of social bonds within the community. Possible factors include excessive group size, competition for food and reproduction, a succession of alpha males, and diseases that killed key individuals linking the different subgroups.
Similar events were observed in Tanzania in the 1970s, but at the time, scientists doubted whether this was natural behavior. In this case, the researchers are confident that the conflict occurred without external intervention.
The authors of the study believe that this case will help better understand the nature of conflict not only in animals but also in humans. They believe it's not so much cultural differences that play a significant role, but rather the breakdown of social ties between groups. 
