The Slow Loris Is You at Happy Hour

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Photo: Visuals Unlimited Inc/Thomas M

If you have never seen this video of a slow loris getting tickled — actually, no, if you are a person who has two eyes and a heart — please, stop reading for a sec and watch it.

Now that that’s out of the way, here’s another fun fact to add to your arsenal of slow-loris facts: Perhaps as much as it loves getting tickled — or perhaps more — the slow loris loves its special juice. According to a new study in the journal Royal Society Open Science, the animal just might be a bit of a lush — a finding that may also bring us one step closer to understanding our own attraction to alcohol.

The study authors, a team of biologists from Dartmouth, conducted their research on one slow loris and two aye-ayes, small nocturnal primates native to Madagascar. The natural diets of both species, the study authors noted, are made up of “chow gruel [and] mealworms,” because no one has ever told them that pizza is actually a superior drunk food, as well as — most important, for these purposes — “a medley of ripe fruit, which is expected to contain trace amounts of alcohol.”

Once a day — over 15 days for the aye-ayes, and five for the slow loris — the researchers presented the animals with servings of two different liquids: an ever-so-slightly alcoholic sugar solution meant to simulate nectar (the researchers varied the concentration from day to day), and tap water as a control. All three primates showed a strong preference for the most alcoholic solutions, even attempting to scoop up any last remaining drops with their fingers once the containers were empty.

As Jason Daley pointed out in Smithsonian, this is far from the first time we’ve seen other species kick back with a drink (or the animal equivalent of a drink): “Butterflies like a little tipple, and YouTube is full of birds that get a little loose after eating fermented berries, and when wasted, slur their songs. One time, a drunk moose even got caught in a tree while stealing fermented apples in Sweden,” he wrote. A 2014 study, meanwhile, found a shared genetic mutation that helps both humans and gorillas to process alcohol.

This latest study, then, isn’t necessarily notable for its discovery that animals like to booze, but it does offer support for one controversial theory about our own relationship with the stuff. In his 2014 book The Drunken Monkey, Robert Dudley, a biologist at the University of California, Berkeley, argued that humans’ alcohol consumption evolved as a byproduct of our ability to sniff out nearby ripe fruit, which often contains ethanol.

“It’s not just Napa vineyards and drunks on the street. There is actually a much broader natural background of alcohol production within fruit and consumption by tens of thousands of species of animals,” Dudley told LiveScience at the time. The uniquely human practice of fermenting our own alcoholic substances, then, may stem from a pattern of behavior that isn’t actually unique to us at all.