It turns out ‘let’s have a drink together’ isn’t just a human line — primates do it, too. Researchers at the University of Exeter documented chimpanzees sharing alcohol for the first time. Motion-sensor cameras in Cantanhez National Park in Guinea-Bissau captured chimpanzees exchanging fermented African breadfruit, which contains ethanol. The team described the behavior in a paper in the journal Current Biology.
What did the team find? The researchers say the chimps’ shared drinking could reflect social bonds similar to those in humans. “We have documented for the first time the repeated and communal consumption of naturally fermented African breadfruit by wild chimpanzees, with confirmed ethanol content,” the paper says. The researchers hope the observations will shed light on whether chimpanzees intentionally seek ethanol-containing fruits and how they metabolize alcohol. “Chimpanzees do not share food all the time, so this behavior with fermented fruits could be significant. We need to learn more about whether they intentionally seek out fruits containing ethanol and how they metabolize it; this behavior could represent an early evolutionary stage of feasting,” said Kimberly Hawkins, the lead researcher.
They tested the fruits and found up to 0.6% ABV — low by human standards (beer is usually 4–6% ABV). But because fruits make up as much as 85% of a chimpanzee’s diet, the total ethanol intake could add up, the Independent reports.
The team says the finding may be just the tip of the iceberg in understanding primate alcohol behavior. “We know that alcohol consumption in humans leads to release of dopamine and endorphins and to feelings of happiness and relaxation. We also know that sharing alcohol, especially in social traditions like partying, helps form and strengthen social bonds,” said Anna Bowland, a co-author. Seeing primates drink together raises several complex questions about chimpanzee behavior.
Overall, the study suggests that eating fermented fruit may have deep evolutionary roots shared by humans and chimpanzees. The authors also propose that human feasting traditions could stem from these ancient behaviors. But researchers still don’t know how alcohol affects chimpanzee metabolism.
