Research

Study: Ongoing Conflict Spurs Rare Community Split in Chimps

Is this a historic datapoint in documenting chimpanzee evolution, or are there implications for other primate societies too — including humans?

Published APR 10

Study: Ongoing Conflict Spurs Rare Community Split in Chimps

Story

Above: Chimpanzees at the Barcelona Zoo, on Aug. 5, 2025. Image credit: David Zorrakino/Europa Press/Getty Images

The Facts

A study published in the journal Science, drawing on 30 years of demographic data and behavioral observations, has documented what's described as a rare permanent split in the largest known group of wild chimpanzees, the Ngogo community in Uganda's Kibale National Park.
Science
Fox 21 online
The Ngogo chimpanzee community, which numbered nearly 200 individuals, began fracturing in 2015 before fully dividing into two distinct groups — the Western and Central clusters — by 2018. Social, spatial and reproductive ties between the two groups ceased entirely after the split.
guardian
Wionews
Science
Researchers identified several factors that may have contributed to the split, including the 2014 deaths of five adult males and one adult female, a change in alpha male in 2015 and a respiratory disease outbreak in 2017 that killed 25 chimpanzees.
ThePrint
Science
Following the permanent fission, members of the Western group carried out 24 coordinated attacks on the Central group between 2018 and 2024, killing at least seven adult males and 17 infants. Researchers noted the true death toll is likely higher, as many individuals disappeared without confirmed cause.
Fox 21 online
Wionews
The only previously recorded comparable event occurred in the 1970s, when Jane Goodall observed a violent split among chimpanzees in Tanzania's Gombe National Park. That case has remained contested because the chimps were regularly provisioned with food by researchers, which may have altered their behavior.
The New York Times
Scientific American
Genetic evidence suggests permanent fissions in chimpanzee communities occur roughly once every 500 years. Researchers said human activities such as deforestation, climate change and disease outbreaks could make such conflicts more frequent.
Wionews
Science

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The Spin

Narrative A

The smaller Western chimp faction proved that tight social bonds beat sheer numbers — launching 24 coordinated attacks and killing at least seven adult males and 17 infants from the larger Central group. Documenting this rare fission is crucial for a better understanding of chimpanzee behavior and evolution.

Science

Scientific American

Narrative B

This "chimp civil war" is more broadly a mirror held up to humanity itself — violence erupted not from ideology but from broken personal bonds, proving relational collapse alone can ignite lethal conflict. It's vital to fund the field of primatology to help illuminate how conflicts can fester in the societies of both humans and our closest animal relatives.

ThePrint