Big news in the field of alcoholic fruit fly research—when fruit flies are offered unlimited amounts of alcohol, they drink until they pass out. They don't know when to say when, much like their human counterparts, alcoholics.
"The flies choose to consume alcohol to intoxicating levels, they will do so even if alcohol is made unpalatable, and they relapse to drinking high levels of alcohol after being deprived of it," said Ulrike Heberlein of the University of California, San Francisco. "Addiction is a purely human condition, but, surprisingly, flies show several key features of it."
If Heberlein's name sounds familiar, it's because she has been getting fruit flies drunk for years (as I wrote about here).
Heberlein and her colleagues offered fruit flies the choice between ethanol-laden food and food without it. The smell of the booze attracted the fruit flies, and they would consume it even though they didn't like the taste (I wonder how Heberlein can tell if a fruit fly doesn't like the taste of food? Do they gag?) And much like college students ignore a dislike of cheap beer in order to get drunk, fruit flies ignore their distaste of booze to eat the intoxicating food. If the flies are deprived of the sauce for a while and then given it again, they will revert to their binge drinking behaviors and consume until intoxication. Heberlein says this provides insight into more complex alcoholic behaviors, such as relapse. There is something rewarding enough about alcohol encouraging the flies to continue to imbibe.