Our attraction to alcohol seems to go back millions of years. Our primate ancestors inherited it from us. They discovered that the smell of alcohol led them to ripe, fermented fruits. Yes, primates are attracted to alcohol.
Drunken monkey theory
A new study now supports this idea. UC Berkeley biologist Robert Dudley defined it in 2014 as the “drunk monkey” hypothesis.
The study was led by primatologist Christina Campbell. She works at California State University, Northridge (CSUN). She collected fruit consumed and discarded by black-handed spider monkeys in Panama. They found that the alcohol concentration in the fruit was typically between 1% and 2% by volume. A by-product of natural fermentation by sugar-eating yeasts in the ripe fruit.
The urine of these monkeys contained secondary metabolites of alcohol. They were using it for energy, not just passing it through their bodies. “For the first time we show that wild primates, without human interference, consume ethanol containing fruit.” Said Campbell in a statement. “There is some truth to that ‘drunken monkey’ hypothesis. The propensity of humans to consume alcohol stems from a deep-rooted affinity of frugivorous primates.”
How it affects them
Dudley presented evidence for his idea eight years ago. He did so in the book “The Drunken Ape: Why We Drink and Abuse Alcohol.” Some fruits eaten by primates have a high natural alcohol content. Up to 7%.
“(The study) is a direct test of the drunken monkey hypothesis,” the researchers said. Primates are attracted to alcohol.
“First part, there’s ethanol in the food they eat, and they eat a lot of fruit. Then, second part, they’re actually metabolizing the alcohol. What we don’t know is how much they’re eating and what the behavioral and physiological effects are. But it is confirmatory,” he explained.