Primatologist John Mitani Documents First Wild Chimp Civil War — SkimNews
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- John Mitani co-founded the Ngogo Chimpanzee Project in 1995 with Yale primatologist David Watts using a $500,000 US National Science Foundation grant, documenting a community of nearly 200 chimpanzees — then the largest known wild chimp population.
- A male chimp Mitani named Hare became the first ape to trust the researchers after a 25-year-old with a cleft palate descended from a fig tree and let Mitani follow, breaking through years of the chimps fleeing human observers.
- Mitani's team recorded findings that stunned primatology: the lowest mortality ever documented for wild chimps, unrelated males forming alliances, and hunting red colobus monkeys serving as social bonding rather than just nutrition.
- Starting in June 2015, researchers witnessed what became a years-long lethal conflict — by 2018 the group had split into two distinct communities, with 9 males and 19 infants killed, as chronicled in Netflix's 2023 series Chimp Empire.
- The study, published in Science in April 2025, found that the split unexpectedly doubled female fertility and increased offspring survival — but Mitani says watching it unfold was deeply personal and resisted drawing evolutionary parallels to human violence.
- The 30-year project now faces elimination of its primary NSF funding under the Trump administration's proposed 2027 budget, with Mitani warning of 'the war on science and truth' endangering future discoveries at Ngogo.
- Mitani, now 72, estimates he has spent 85 months hiking Ngogo's forests and says the site's chimps 'have many more important stories to tell us' beyond the civil war.
Why it matters: Mitani's paper marks the first peer-reviewed documentation of lethal group-splitting violence among wild chimpanzees — a finding with direct implications for theories of how our closest relatives form and break alliances. The research's survival depends on roughly $500,000-scale NSF grants now slated for elimination in the Trump administration's 2027 budget, putting one of only 12 long-term wild chimp studies worldwide at risk alongside any future insights it might yield.
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