This article originally appeared on VICE Romania.
I recently found out that some species of birds are known to have a drug habit. Before you nod off into some daydream about birds railing lines in a bar toilet, let me explain.
A while back, I stumbled across a 65-year-old scientific paper produced by American entomologist and ornithologist Horace Groskin. There was one particular sentence in the essay that really caught my attention: "Birds use the ants to anoint themselves with the formic acid excretions of the ant to give tone to the muscles and also for the general agreeable effect."
An agreeable effect, eh? Apparently, this behavior is called "anting" and involves grabbing a bunch of ants and rubbing them under your wings. As a means of defense, ants omit formic acid—an organic insecticide—which then gets absorbed by the bird's body. People have reported seeing birds dancing around with their wings stretched out and their beak wide open, right after having covered themselves with this gross ant spray. A sort of ornithological gurning, if you will. This has led many smart professor types to believe that the act of anting is a vice and that birds do it to get, well, mad-out-of-it.
I decided to ask an expert from the Romanian Ornithological Society about the phenomenon. Ornithologist Stefan Emanuel Baltag told me that anting was quite common amongst several species of birds—namely, the hoopoe, the common starling, the mockingbird, the kestrel, the raven, the crow, and the chaffinch.
"Some birds fly up on top of an anthill, sit down still, and then patiently wait for the ants to crawl up into their feathers. This is called 'passive anting.' Other species pick the ants up with their beaks and actively wipe their excretion all over themselves. This is known as 'active anting.' One explanation for this is that birds use the ants' formic acid as a stimulant, much like people smoking or taking drugs," he explained to me.
The ants accumulate this acid in a gland and save it to spray at a predator if they feel threatened. Formic acid actually gets its name from the Latin word for ant, "formica." When active anting, the birds repeatedly flap their wings so the excretion is evenly distributed all the way to the bottom of their feathers.
It's quite easy to examine formic acid—all you need to do is place your hand over an anthill and you'll end up with a layer of stinking secretion on your palm.
Baltag added that there have been cases of birds rubbing themselves in the secretion of other species like centipedes, snails, caterpillars, and wasps, too. One can only imagine what that's good for.
Even though it's widely accepted that birds engage in anting for kicks, there's a bunch of other theories also floating about. "There's no definitive answer as to why birds engage in this kind of behavior. Depending on their species, birds can use anting to get rid of parasites, to sooth irritation, or as a way to reach a euphoric state," Baltag concluded.
Unsurprisingly, it's still unclear whether rubbing ants into your armpits has any effect on humans.