Humans aren't the only creatures that change their behavior under the influence of alcohol. According to new findings by researchers at Penn State, the sexual behaviors of fruit flies change after being exposed to ethanol.
Researchers led by Kyung-An Han, associate professor of biology and neuroscience, observed and filmed the behaviors -- especially those sexual in nature -- of adult male fruit flies after being exposed to ethanol, the ingredient in alcohol that causes intoxication.
"We were looking at fruit flies and were trying to see what exactly is causing the sexual aggression and sexual behavior that we were seeing when exposing these fruit flies to ethanol," said Jennifer Dunning (senior-chemical engineering and general science), an undergraduate researcher for the experiment.
Although the study unveiled interesting results, it began accidentally.
"It kind of came upon us ... " Dunning said. "I was looking at [the flies] in the lab and saw the males courting each other and was like, 'Hmm, I wonder if they saw this before.' "
Penn State Live called the study's findings a "physiological basis for the effect of alcohol on male sexual behavior."
During the experiment, which consisted of several different parts, researchers exposed about 30 male fruit flies at a time to ethanol and then let them "do their thing" while taping the behaviors, Dunning said.
After a few days, researchers watched the tapes to see how many of the male fruit flies were courting, which involved them following and tapping each other, moving their wings and appearing to try to copulate, Dunning said.
"We found that through the exposure of ethanol, the males do court each other a lot," she said.
Researchers identified three different components that were crucial to the ethanol-induced courtship and the sexual disinhibition of the male flies: the neuromodulator dopamine, the ABC guanine/tryptophan transporter and the transcription factor regulating male sex behavior, Dunning said.
"This [behavior] is kind of parallel to when college students go out or when human beings go out to the bars," Dunning said.
Some Penn State students also commented that they have witnessed a connection between drunkenness and increased sexual behavior in human men.
Janai Curtis (freshman-biology) said the mentality of intoxicated human men seems to be "alright, I'm up for anything."
"Guys are usually homophobic," Meghan Lyons (freshman-nursing) said. When they drink alcohol, though, "they're more relaxed, so they touch each other more," she said.
Aaron Crapser (junior-telecommunications) agrees that alcohol brings out more openly homosexual behavior in men but disagrees that there is a link between human and fruit fly behavior.
"They were fruit flies. Drunk fruit flies," he said. "They're much lower in the hierarchy [than humans]."
After all is said and done, Amanda Rood (junior-wildlife and fisheries science) said she thinks alcohol has little to do with men's true feelings. "To tell another guy you love them when you're sober is completely different than to tell them you love them when you're drunk," she said.
