Drunk males get hornier and hornier the more they drink...to the point they start chasing anything, even other males. Problem is, though they get far more interested in having sex, their performance declines the more they drink.

All of that according to a study from the lab of Kyung-An Han, a neurobiologist at Pennsylvania State University, and reported in Nature News. Oh...the study was done on fruit flies (Drosophila melanogaster).

From the article on Nature News:

In the flies, hypersexuality caused by chronic alcohol exposure has the effect of making the males chase anything with wings — other males included. Although sexual preference in humans is obviously a complex phenomenon not replicated by the fly work, the findings could be used to further establish a fly model system for the study of alcoholism, observers say...

As the concentration of ethanol in the body rises, flies begin to become uncoordinated and oblivious to their surroundings: they get tipsy. “They bump into each other. They bump into the walls,” says Heberlein.

Add more alcohol and the flies become sedated. Add still more and the soused flies die. Remarkably, even the concentrations of ethanol that induce these behaviours are nearly the same in flies and humans, says Heberlein. Flies also develop a tolerance to alcohol, and can develop withdrawal-like symptoms...

The effect of ethanol on mating behavior is particularly interesting, and may be of interest to people on their way to their next fraternity party:

The researchers noted that male flies repeatedly exposed to ethanol vapour became less discriminate in their mate selection. The buzzed flies often courted fellow males, pursuing them around the cage while serenading with a traditional fruitfly courtship song played on vibrating wings.

Eventually, the lusty flies devolve into a courting frenzy. “You get a chain of males chasing each other,” says Heberlein, who was not associated with the study but has observed similar behaviour in her own unpublished work. In contrast, alcohol had little effect on mating in female fruitflies, which normally do not court their mates...

Although the drunken [flies] were more amorous, their rates of successful copulation declined after getting tipsy, the researchers found — a trend that has long been observed in humans. Anholt notes that William Shakespeare even described the phenomenon in his play Macbeth when he wrote that alcohol “provokes the desire, but it takes away the performance".

I guess there isn't the same effect on female fruit flies, meaning the wine cooler (or other "chic drink") phenomenon wouldn't apply to fruit flies.