It's long been known that occasionally wild animals inadvertently get drunk from snacking on ferment fruits. Turns out though that it may not be that rare as one might think. Nature's booze may also may be good for them.
"Ethanol is far more common in nature than we previously realized," says Kimberley Hockings, a behavioral ecologist at the University of Exeter. "For animals that rely on sugary fruits, regular exposure to some level of ethanol is almost unavoidable."
Ethanol has been part of the environment for millions of years, since flowering plants began producing nectar and fruits that could be fermented by yeast. In tropical climates, fruit can reach surprisingly high alcohol levels—up to 10.2% ABV in some cases. That doesn't necessarily mean they're looking to get crunk though.
"From an ecological perspective, it is not advantageous to be inebriated as you're climbing around in the trees or surrounded by predators at night—that's a recipe for not having your genes passed on," says College of Central Florida molecular ecologist Matthew Carrigan. "It's the opposite of humans who want to get intoxicated but don't really want the calories—from the non-human perspective, the animals want the calories but not the inebriation."
From Cell Press:
It's unclear whether animals intentionally consume ethanol for ethanol's sake, and more research is needed to understand its impact on animal physiology and evolution. However, the researchers say that ethanol consumption could carry several benefits for wild animals. First and foremost, it's a source of calories, and the odorous compounds produced during fermentation could guide animals to food sources, though the researchers say it's unlikely that animals can detect ethanol itself. Ethanol could also have medicinal benefits: fruit flies intentionally lay their eggs in substances containing ethanol, which protects their eggs from parasites, and fruit fly larvae increase their ethanol intake when they become parasitized by wasps.
"On the cognitive side, ideas have been put forward that ethanol can trigger the endorphin and dopamine system, which leads to feelings of relaxation that could have benefits in terms of sociality," says behavioral ecologist and first author Anna Bowland of the University of Exeter. "To test that, we'd really need to know if ethanol is producing a physiological response in the wild."
Previously:
• A harrowing reminder that wild animals are not pets
• Rainforest mammal spotted 3,000 miles away in Washington state
• Yellowstone visitors, please don't pick up baby wild animals and drive them around
