Title: Alcoholic Connections in the Wilderness: Chimpanzees Share Fermented Fruits in Guinea-Bissau
Deep within Cantanhez National Park, situated in a secluded area of Guinea-Bissau, researchers have made a finding that could alter our understanding of human drinking habits and their evolutionary beginnings. Wild chimpanzees, our closest evolutionary kin, have been filmed repeatedly indulging in and distributing naturally fermented fruits—fruits containing detectable levels of ethanol, commonly referred to as alcohol.
This remarkable behavior was recorded utilizing motion-sensor cameras set up by scientists from the University of Exeter. Throughout a three-month span from April to July 2022, researchers documented ten separate instances where chimpanzees opted for and shared African breadfruit that had fermented. These observations spark fascinating conversations about the origins of alcohol consumption and the social aspect of feasting—two behaviors traditionally thought to be exclusive to humans.
The ‘High’ of the Breadfruit
The African breadfruit consumed and shared by the chimpanzees was far from ordinary, particularly by the end of its maturation. As the fruit ripens, it may begin to undergo natural fermentation, resulting in ethanol production. Field researchers, using portable breathalyzers, tested numerous fruit samples and found that 86% contained noticeable amounts of alcohol, with levels varying from 0.01% to 0.61% alcohol by volume (ABV). Although this may appear minor compared to beverages like beer or wine, it represents a considerable volume given the fruit-centric diets of chimpanzees.
Curiously, the most fermented fruits—those that had matured into a soft, mushy texture—were the ones most frequently exchanged. These “fully ripe” fruits averaged 0.26% ABV and were a feature in half of the recorded fruit-sharing instances.
Beyond a Snack—A Cultural Custom?
In the majority of the video-documented events, chimpanzees were observed willingly sharing the fermented fruit, doing so amicably even when fresher options were readily available. In several instances, chimps chose to ignore less fermented breadfruits in favor of their more alcoholic versions—suggesting a preference or deliberate choice.
“Chimps don’t regularly share food, so their behavior with fermented fruit might carry significance,” noted Dr. Kimberley Hockings from the University of Exeter. “We need to further discover if they intentionally seek out ethanolic fruits and how they process them, but this behavior could represent the early evolutionary stages of ‘feasting’.”
The ramifications are profound. In humans, alcohol is known to provoke the release of dopamine and endorphins—chemicals tied to pleasure and mood regulation. Drinking has been woven into various cultural practices and social rituals throughout human history. Researchers now ponder: could chimpanzees derive similar neurochemical rewards from these shared experiences with fermented fruit?
Evolutionary Reflections of Human Actions
The notion that alcohol consumption might predate human society isn’t entirely novel. Genetic studies have indicated that a mutation enabling better alcohol processing appeared around 10 million years ago in a common ancestor to African apes, including humans and chimpanzees.
These recent discoveries bolster the evidence for this longstanding evolutionary link. It’s plausible that our ancestors incorporated fermented fruit into their diets long ago—possibly reaping not just caloric and nutritional benefits but also social ones.
More Than a Social Event: Benefits of Fermented Fruits
Fermented fruits are not merely an intoxicating indulgence. Their softer consistency reduces the effort needed for consumption—especially vital when food requires strong jaws or tools to access. As fermentation diminishes a fruit’s chemical defenses, it becomes more energetically efficient to eat. Additionally, fermentation typically boosts nutritional value, enhancing vitamin content—making these fruits a significant part of the diet.
For chimpanzees, larger and scarcer fruits like the African breadfruit may occupy a special place in their culinary culture, similar to a prized dish at a human feast. Their relative rarity and perceived ‘premium’ status render them perfect for sharing within close social groups.
Chimpanzees Reflecting Human Culture
The recorded footage from Guinea-Bissau provides further astonishing insights into chimpanzee behavior. From crafting tools and establishing grooming hierarchies to potentially engaging in social drinking, chimpanzees continue to demonstrate traits and actions once thought to be unique to humans.
“If this is the case,” Dr. Hockings concludes, “it implies that the human custom of feasting might have its roots deeply embedded in our evolutionary past.”
What Lies Ahead?
While these revelations are striking, researchers emphasize the necessity of more extended observations for concrete conclusions. Upcoming studies aim to track the behaviors of individual chimpanzees over longer periods, monitor shifts in social dynamics, and evaluate consumption trends across different seasons and fruit availability. Understanding how chimpanzees metabolize alcohol could also clarify whether their consumption is a conscious choice, accidental exposure, or perhaps something in between.
Nevertheless, this discovery casts a new perspective on the