Researchers have for the first time filmed wild chimpanzees feasting on alcoholic fruits together. It’s the “first evidence for ethanolic food sharing and feeding by wild nonhuman great apes,” they say in a new study.
The research team, led by scientists at the University of Exeter, U.K., captured the footage on camera traps they set up in Cantanhez National Park in southern Guinea-Bissau.
The cameras recorded wild western chimpanzees (Pan troglodytes verus) sharing African breadfruit (Treculia africana) with each other on 10 different occasions. In one instance, a chimp even snatched a piece of fruit from another individual’s mouth.
Once mature, the fleshy, fibrous, volleyball-sized African breadfruits drop from trees to the ground, where they ripen further. Chimps can feast on such fallen fruits over multiple days, the researchers say.
The team found that 90% of the fruits the chimps ate and shared contained some level of ethanol, reaching up to 0.61% alcohol by volume (ABV). Beers typically have 4-8% ABV, while wine has about 12-16% ABV.
While the alcohol content in the fruits is very low compared to these drinks, chimps can consume large amounts of fruit daily, which means all the alcohol can add up. “They can feed on kilograms of the stuff every day. It’s probably analogous to us sipping on a light beer,” study co-author Kimberley Hockings from the University of Exeter told The Guardian.
Hockings and her colleagues have previously found that many different kinds of animals consume ethanol-rich fruits, from tiny flies, wasps and bees, to monkeys, chimps and elephants. In 2015, they published a study describing a group of wild chimpanzees in Guinea that would regularly use folded leaves to drink fermented alcoholic sap that people in nearby communities collected from raffia palms and left to brew.
Whether Cantanhez National Park’s chimps seek out the fermented, slightly alcoholic breadfruits deliberately for reasons other than nutrition — and if so, why — still remains unknown. However, sharing alcohol among humans is linked to social bonding, and that could be the case with the chimps too, although it hasn’t been studied yet, the authors write.
Robin Dunbar, an evolutionary psychologist from the University of Oxford in the U.K., who wasn’t involved in the study, told The Washington Post that he agreed there could be some social benefit to sharing bits of fermented fruits, but the psychobiological consequences remain to be investigated.
“Chimps don’t share food all the time, so this behaviour with fermented fruit might be important,” Hockings said in a statement. “We need to find out more about whether they deliberately seek out ethanolic fruits and how they metabolise it, but this behaviour could be the early evolutionary stages of ‘feasting.’ If so, it suggests the human tradition of feasting may have its origins deep in our evolutionary history.”
Banner image: Two adult male chimpanzees in Cantanhez National Park in southern Guinea-Bissau eat fermented African breadfruit. Image by Bowland et al., 2025 (CC BY 4.0).
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