On the heels of a study that found chimpanzees to possess an understanding of the cooking process — something once thought to belong only to humans — another new study reveals that chimpanzees can be social drinkers, too.
In a 17-year study, scientists found that chimps, who share the human ability to metabolize ethanol, were more than happy to take advantage of the effects of an alcoholic beverage or two, especially if they were among friends.
The drink in question is derived from the raffia palm in Bossou, Guinea, which produces a fermenting sap that is commonly collected into plastic containers and consumed within a day by humans.
Chimpanzees, on the other hand, have been observed ingesting the sap using a drinking tool — often a leaf-scoop or a leaf-sponge that “is immersed in the fluid, then retrieved and inserted into the mouth for compressive extraction between the tongue and palate.”
Chimpanzees were seen both drinking alone at the top of a palm tree, and engaging in “drinking sessions” in groups. The alcohol content of the sap ranged from 3.1 percent to 6.9 percent. Unsurprisingly, the chimps were observed during these two decades of research occasionally displaying “behavioral signs of inebriation” after drinking.
The findings support what is known as the “drunken monkey hypothesis,” which states that natural selection favors primates with an “attraction” to alcohol because of its evolutionary benefits — stimulating one’s appetite or indicating, by the odor of overripe fruit, where food sources might be found.