A US study has discovered that African chimpanzees routinely consume alcohol naturally present in overripe fruit that, given the size of their bodies, would be equivalent to having two drinks a day, suggesting that human addiction to alcohol has an evolutionary root.  

Scientists from UC Berkeley visited Uganda’s Kibale National Park and Taï National Park in Côte d‘Ivoire to study chimpanzees’ regular diet. There, they recorded how often chimpanzees eat each type of fruit and collected fallen fruit at sites where they had been foraging to analyse their ethanol content. In both parks, chimps preferred the fruit with the highest amount of ethanol, suggesting that alcohol is a regular part of their diets. 

“Human attraction to alcohol probably arose from this dietary heritage of our common ancestor with chimpanzees,” said Aleksey Maro from UC Berkeley, first author of the study.  

Lead author, Robert Dudley from UC Berkeley, added, “One of the reasons this has been a tempting target but no one’s gone after it is because it’s so hard to do in a field site where there are wild primates eating known fruits. 

This research, published in Science Advances, provides a foundation for studying primates’ natural behaviour and their preferences for alcohol.