Study reveals that when eating fermented fruits, chimpanzees eat 1.4 daily doses of alcohol. Habit may be linked to evolutionary roots shared with humans.
They do not realize (for obvious reasons), but due to the fermented fruits they ingest, The chimpanzees drink alcohol. Every day.
More precisely, these animals consume the equivalent of 1.4 daily alcoholic doses, or a beer, according to a study in Science Advances magazine.
The investigation, conducted by an international team of scientists and coordinated by the University of California in Berkeley, was made with wild chimpanzees in Uganda and Ivory Coast. The study found that male chimpanzees and females consume about 14 grams of pure ethanol per day“What is equivalent to a standard alcohol in the US”, or a can of 350 ml beer, corresponding to one dose.
But comparatively, it’s like it was more. This is because, on average, a chimpanzee weighs about 40 pounds, against 70 kilos of a human, which means that the final intake is superior to one drink a day, explains Aleksey Marofrom the University of California and the main author of the study.
Although it is unclear whether animals are looking for fruits with high ethanol levels – found in the most mature fruits, with more fermenting sugars – it is certain that alcohol is an ordinary part of their diet and was probably also part of the human ancestors’ diet, according to researchers.
The daily dose
Scientists believe that studying this behavior in primates in nature can help explain why the attraction of human beings through alcohol persists.
Therefore, the team examined the amount of alcohol ingested by chimpanzees through food and quantified the concentrations of ethanol in 21 fruits collected in the NGOGO forest, Uganda, between 2017 and 2018, and at Taï National Park, in Ivory Coast, in 2021.
They concluded that, on average, the fruits contained 0.32% and 0.31% ethanol in the samples of each country, respectively. The study indicated that, in Uganda, the most consumed fruit was the figo. On the ivory coast, it was a similar clam. And they are precisely these contain more alcohol.
Given that chimpanzees usually eat about 4.5 pounds of fruits per day, it is estimated that animals consume the equivalent of 1.4 drinks daily.
“Chimpanzees eat between 5% and 10% of their body weight a day in ripe fruits. Even fruits with low concentrations produce a considerable dose of alcohol, which leads to a high total daily,” he notes Robert Dudleyprofessor at the University of California and co -author of the study.
Consumption of these and other fruits occurs throughout the day, and therefore the chimpanzees do not show signs of intoxication. In fact, according to the authors, to be drunk, they would have to eat so much fruit that their stomachs would be swollen.
The hypothesis of the drunk monkey
For researchers, the consumption of ethanol by these animals in nature reinforces the hypothesis, proposed by Dudley in 2016, “Drunk Monkey”which suggests that the attraction of humans through alcohol has its origin in the behaviors of the first hominids.
According to Dudley, the animals look for ethanol because the smell It helps them find foods with greater sugar, which gives them a higher energy return over time. In addition, alcohol also can increase the pleasure of eatingsimilar to what happens when drinking wine during dinner, and it is possible to share fruits with alcohol influence social ties between primates or other animals.
The study shows that chimpanzees consume ethanol chronicly and this, according to Dudley, could be transmitted Even the ordinary ancestors of humans and chimpanzees, who were also daily exposed to alcohol from the fermentation of fruits.
“Chimpanzees consume an amount of alcohol similar to what we would consume if we had fermented daily foods. Human attraction to alcohol probably arose from this food heritage of our common ancestor with chimpanzees,” Maro concludes.
