First Date Nerves? Fruit Flies Show Why

A cluster of nerve cells linked to sexual behavior could mean the difference between being a success with the ladies or a dismal failure — at least in fruit flies.

A cluster of nerve cells linked to sexual behavior could mean the difference between being a success with the ladies or a dismal failure — at least in fruit flies.Scientists who isolated the cells that control courtship in the male fruit fly believe their findings could hold clues about sexual behavior in other species, including humans. “The fruit fly is a model organism whose basic cellular functions are very similar to what they are in people,” said Bruce Baker, of Stanford University in California. “It wouldn’t surprise me to learn that human sexual behaviors also have underneath them a basic circuitry in the nervous system that mediates attractions and mating.” Baker and his colleagues had previously identified the master gene, dubbed fruitless, that controls sexual behavior in male fruit flies. “We found that the fruitless gene was responsible for building the neuronal circuitry for male courtship,” Baker said in a statement. In research published in the science journal Nature on Wednesday, he reported that 60 cells are involved in sexual behavior. When they don’t work properly, male fruit flies cannot complete specific steps of the courtship ritual and are unable to reproduce. When the researchers interfered with the nerve cells, the fruit flies did not do all of the steps, such as tapping the female, extending and vibrating a wing and singing, and rushed through the courtship — which the females did not find attractive. The altered males essentially try to do everything at once, according to Baker. Baker and his colleagues speculated whether genes that control sexuality in fruit flies could have a similar role in humans. “If you look at the basics of fly behavior, you find an innate ability to recognize somebody who is the right species and is the right sex,” said Baker. “You tap them and get their attention, you play them a love song and so on. So the basic rudiments are pretty similar to what people do to get successful mating and produce an offspring.” (SOURCE: Nature: Reuters Health News: July 2004.)