First rat sex, now this…Did you ever wonder what drives a fruit fly (aka drosophila melanogaster) to drink? If you’re anything like us, this question keeps you up at night (Let’s hope you’re nothing like us). Well, based on research out of the University of Missouri, it looks like sexual rejection is a prime instigator of fruit fly alcoholism.1 That’s right. Researchers explored the sexual habits and alcohol consumption of fruit flies and found that flies experiencing sexual rejection consumed more alcohol.
Researchers took a group of 24 male fruit flies and randomly placed them in either a container that allowed the flies to freely mate with several interested female fruit flies (think of it as the fruit fly version of Spring Break in Daytona Beach), or in a container that contained female fruit flies that already mated. It’s important to note that female fruit flies who have recently mated will refuse to mate again, no matter what crafty mating moves the male fruit flies employ.
After experiencing these conditions for several days, both groups of male fruit flies were placed into a new area where they had the choice of eating either plain food or food mixed with alcohol. Interestingly, the flies that spent the last 4 days mating avoided the alcohol-laced food. In contrast, the sexually rejected and deprived flies preferred the food with alcohol and ingested four times more alcohol than the flies in the “free love” condition. When the researchers examined the fruit flies’ brains, they discovered that consuming alcohol and mating activated the same neurological pathway; in other words, the abstinent flies were going to get ‘some’ one way or the other.
Clearly, male fruit flies’ behavior may not perfectly map onto human behavior. That is, we can’t be sure from this study whether sexual rejection leads human males to seek out alcohol. But it does open up the possibility of studying whether these neurological pathways operate similarly in humans. It may be that in humans other behaviors like shopping or eating chocolate could activate similar reward systems as sex. There is evidence to suggest this is indeed the case.2 In any case, as you and your fellow bar flies are buzzing about the local watering hole, this research should make for an interesting topic of conversation.
1Shohat-Ophir, G., Kaun, K. R., Azanchi, R., & Heberlein. U. (2012). Sexual deprivation increases ethanol intake in drosophila. Science, 335 (6074), 1351-1355. doi: 10.1126/science.1215932
2Fisher, H. E, Brown, L. L., Aron, A., Strong, G., & Mashek, D. (2010). Reward, addiction, and emotion regulation systems associated with rejection in love. Journal of Neurophysiology, 104, 51-60.
Dr. Gary Lewandowski – Science of Relationships articles | Website/CV
Dr. Lewandowski’s research explores the self’s role in romantic relationships focusing on attraction, relationship initiation, love, infidelity, relationship maintenance, and break-up. Recognized as one of the Princeton Review’s Top 300 Professors, he has also authored dozens of publications for both academic and non-academic audiences.
image source: beerymethod.com