It's not just humans who love to sit back and sip on an alcoholic beverage ... wild chimps do too. Chimpanzees have been discovered pilfering palm "wine" collected by humans from trees in Guinea in Western Africa by an international research team including primatologists from Kyoto University.
A young chimpanzee drinks palm "wine" from a tank using a leaf. (Provided by Kyoto University’s Primate Research Institute)
It's the first time a wild animal species has been found habitually consuming alcohol.
Professor Tetsuro Matsuzawa said he wasn't sure if the chimps could enjoy the buzz from the booze.
“But I was impressed to see them looking content as they walked off from drinking sites,” added the researcher, who works at Kyoto University’s Primate Research Institute.
Humans harvest the beverage from raffia palms. They make cuts on trees that are no taller than 10 meters and collect the sap that drips out. The sap ferments within a few hours into a cloudy beverage. The alcohol content is 3.1 percent on average, but can reach as high as 6.9 percent.
The researchers, who have been observing chimps in Guinea since 1976, have witnessed a total of 51 chimps pilfering palm wine from fermentation tanks arranged by local residents on 20 occasions between 1995 and 2012.
The chimps who were spotted enjoying a drink included both male and female adults and also one ape that was only 6 years old.
While local residents place leaves over fermentation tanks to prevent bugs and impure substances from entering, the apes used the leaves as tools to dip into the liquid and later lick it off.
The chimps even folded and crumpled the leaves to make a kind of impromptu sponge so when they dipped the tool into the tanks they could withdraw a much larger quantity of liquid.
Their report, titled “Tools to tipple: ethanol ingestion by wild chimpanzees using leaf-sponges,” has been published online in the Royal Society Open Science Journal.
Source:
By AKIYOSHI ABE
http://ajw.asahi.com/article/sci_tech/science/AJ201507290004
Kommentare
