The world's largest known group of wild chimpanzees has split and been locked in a vicious civil war for the last eight years, according to researchers.
It is not clear exactly why the once close-knit community of Ngogo chimpanzees at Uganda's Kibale National Park are at loggerheads, but since 2018 the scientists have recorded 24 killings, including 17 infants.
These were chimps that would hold hands, lead author Aaron Sandel said. Now they're trying to kill each other. The study, published in the journal Science, says the intensity and duration of the violence may inform how early human conflict developed.
Sandel, an anthropologist from the University of Texas in the US, and co-director of the Ngogo Chimpanzee Project, states that chimpanzees are very territorial and have hostile interactions with those from other groups.
Over several decades, the nearly 200 Ngogo chimpanzees lived in harmony, divided into two sets known as Western and Central. The conflict began to emerge in mid-2015 when the Western chimpanzees ran away, chased by the Central group.
Initially characterized by typical chimpanzee drama involving screaming and grooming, social interactions became tense and infrequent following a dispute that saw a six-week avoidance period between the groups. Since their final separation, members of the Western group began attacking the Central chimpanzees, leading to an alarming death toll.
The researchers have attributed the violence to various factors including competition for resources and male aggression over mating rights. They identified three major catalytic events: the deaths of dominant individuals in 2014, a change in alpha male in 2015, and a respiratory epidemic in 2017 that decimated the population.
These findings prompt researchers to reflect on the nature of human conflict, suggesting that relationship dynamics might be crucial in understanding both chimpanzee and human societies.
