A groundbreaking study has shed light on a fascinating aspect of animal behavior, challenging the long-held belief that alcohol consumption is uniquely human.

The research shows that many animals, including our primate ancestors, have been consuming ethanol — the intoxicating component of alcohol — for millions of years through naturally fermented fruits and saps.

“We’re moving away from this anthropocentric view that ethanol is just something that humans use,” senior author and behavioral ecologist Kimberley Hockings of the University of Exeter said in a press release. “It’s much more abundant in the natural world than we previously thought, and most animals that eat sugary fruits are going to be exposed to some level of ethanol.”

The study takes an eco-evolutionary perspective, finding that ethanol is prevalent in the environment. Various wild fruits, saps, and nectars contain measurable levels of ethanol, affecting a range of species from insects like vinegar flies to primates such as chimpanzees and spider monkeys.

Genetic analysis offers compelling evidence, tracing the evolution of alcohol-metabolizing enzymes back millions of years. A notable mutation, which significantly improved ethanol processing efficiency, emerged around 10 million years ago in the common ancestor of humans, chimpanzees, and gorillas.

“The ADH change would have enabled our ancestors to consume fermented fruit and so exploit this niche with less risk of inebriation,” the authors note in the journal Trends in Ecology & Evolution.

The study also explores why animals might seek out ethanol despite its potential risks. Researchers suggest several benefits, including providing calories, offering medicinal properties, and even enhancing cognitive and social behaviors.

“On the cognitive side, ideas have been put forward that ethanol can trigger the endorphin and dopamine system, which leads to feelings of relaxation that could have benefits in terms of sociality,” the study’s first author and another behavioral ecologist from the University of Exeter, Anna Bowland, said in the release.

However, ethanol consumption carries risks such as impaired motor skills, indicating a complex balance of costs and benefits that likely depends on an animal’s metabolic capabilities and ecological context.

“Ethanol is ecologically relevant and… has shaped the evolution of many species and structured symbiotic relationships,” the researchers conclude, underscoring the significant role alcohol has played in the natural world.