Remember how your college roommate’s reluctance to take out the trash resulted in a fruit fly invasion? Well, as it turns out, garbage odor isn’t the only reason fruit flies hang around frat houses: they like to get drunk too.
Fruit flies get their name because they lay their eggs on old fruit. The maggots then hatch and feed on the yeast and bacteria that make the fruit rot. But these maggots have to battle with horrifying enemies; tiny wasps identify the maggots and lay their eggs inside them. The wasp larvae develop inside the maggots, literally eating them alive from within. But fruit flies have developed a defense to kill their parasites: They get hammered.
And this binge drinking is a good thing. Because if there is anything worse than an apartment full of fruit flies, it’s an apartment full of wasps.
According to the New York Times, Emory University biologist Todd Schlenke made the discovery earlier this week. “Dr. Schlenke was well aware that many insects gain defenses from their food. Monarch butterflies, for example, are protected from birds by the toxic compounds they get from the milkweed plants they eat. To see how alcohol influences the enemies of the flies, Dr. Schlenke unleashed a parasitic wasp, Leptopilina heterotoma.”
“Dr. Schlenke allowed the wasps to attack two kinds of fly larvae: one kind reared on alcohol-free food, and another that ate food spiked with 6 percent alcohol. In the presence of alcohol, the wasps laid 60 percent fewer eggs, possibly because of the fumes wafting from the food. ‘Presumably the wasps felt really ill,’ Dr. Schlenke said.”
Even more amazing is the fact that these flies are aware of the benefits of their actions. Alcohol only had a deadly effect on the wasps if the flies boozed after the eggs were laid inside them. Taking in alcohol as a wasp repellent had little effect.
I could see how this study could easily find its way into frat-house folklore. After all, a bro, after 6-8 beers, might say something like “well dude, it’s natural to like alcohol. Like the fruit flies, it keeps away predators n’ stuff.”
Of course, frat houses use pretty much anything as an excuse to binge drink, so why should any study matter that much to what’s already happening anyway?