Once again, science has proved that chimpanzees aren’t that different from us.
A 17-year study of chimps from the Republic of Guinea found that the animals often consumed so much alcohol — in the form of fermented sap — that they exhibited “visible signs of inebriation.”
Chimpanzees steal their cocktails from nearby villagers who collect the alcoholic sap from raffia palms by tapping holes into trees and letting the sap drip into containers.
Thirsty chimps turn palm leaves into “cups” by folding or soaking them until they hold enough palm wine to tip into their mouths.
Researchers observed that the apes typically drank for about 10 minutes and would sometimes return for another round later the same day. On average, they dipped their leaves into a container about nine times a minute during a drinking session.
The ethanol present in the sap gives it an average 3.1 percent alcohol by volume content — about the same amount of alcohol found in a light beer — but some of the sap measured had an ABV of up to 6.9 percent.
Previous research on how chimpanzees drink water found that a folded leaf can hold up to 1.7 ounces of liquid, which is a bit more than a single U.S. shot glass. During a drinking session, a chimp would consume anywhere from less than an ounce to nearly three ounces of alcoholic sap.
Researchers estimated that some of the apes drank the equivalent of a bottle of wine.
Both adult and juvenile chimps partake of the sap, as do both male and females. However, males were seen drinking 34 of the 51 times that researchers documented the behavior.
And it seems alcohol has a similar effect on chimps as it does on us as they sometimes “displayed behavioral signs of inebriation, including falling asleep shortly after drinking.”
This is the first time researchers have recorded wild chimps consuming alcohol, but further research is necessary to determine if chimps outside of the area drink or if it’s simply a result of living near humans who collect the sap.
The behavior of using tools to consume alcohol is more sophisticated than other documented cases of animals eating fermented fruit or stealing cocktails from tourists like the St. Kitts monkeys in the video below.
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