Overview

• Researchers measured about 0.3–0.4% ethanol in ripe fruits eaten by chimpanzees at Ngogo in Uganda and Taï in Côte d’Ivoire.
• Using long-term dietary records, the team estimated an average intake of roughly 14 grams of ethanol per chimpanzee per day.
• By simple body-mass scaling, that dose is comparable to a pint of beer for a human, though the comparison is illustrative rather than physiological.
• Published in Science Advances by a UC Berkeley–led group including Robert Dudley, the study strengthens the ‘drunken monkey’ hypothesis on fermented fruit exposure in primates.
• The authors say they have not shown active selection for higher-ethanol fruit or clear physiological effects and call for extended observation and urinary metabolite analyses.