SELF-MEDICATING FRUIT FLIES
Fruit flies are getting quite a reputation for indulging in spirits. But don’t call them lushes; they’re really drinking for self-preservation. According to Emory University scientists, a particular type of fruit fly – Drosophila melanogaster – consumes alcohol to “self-medicate”. Why would flies need to do this? To stave off parasites. “We believe our results are the first to show that alcohol consumption can have a protective effect against infectious disease, and in particular against blood-borne parasites,” study author Dr. Todd Schlenke, an evolutionary geneticist at the university, said in a written statement. “It may be that fruit flies are uniquely adapted to using alcohol as medicine, but our data raise an important question: Could other organisms, perhaps even humans, control blood-borne parasites through high doses of alcohol?” The term “high doses” is something of an understatement. The overripe fruit that the fly larvae feed on contains 5 percent to 15 percent alcohol. “They’re essentially living in booze,” Schlenke said of the flies, which are used commonly in biological research.
Schlenke said he wanted to test whether consuming all that alcohol could help fruit flies stave off the so-called “endoparasitoid” wasps that eat the flies from the inside out. So for a study appearing in the journal current biology, the researchers loosed some flies on a petri dish containing fly food (6 percent alcohol on half of the dish and alcohol-free on the other). After 24 hours, 8O percent of the flies that were infected with wasps were on the alcohol side, while only 3O percent of the non-infected fruit fly larvae were on the alcohol side. “The strength of the result was surprising,” Schlenke said. “The infected fruit flies really do seem to purposely consume alcohol, and the alcohol consumption correlates to much higher survival rates.”