BOSTON, Mass. (Nov. 23, 2010) Pity the female fruit fly. Being a looker is simply not enough. To get a date, much less a proposal, you have to act like a girl, even smell like one. Otherwise, you might just have a fight on your hands.
Like most animals, fruit flies must distinguish between a potential mate and a potential competitor. When a male fruit fly suspects he's encountered a female, he'll court; when he senses the other is a male, he'll fight. What triggers these sex-specific responses?
According to new research by scientists at Harvard Medical School, the answer lies with both pheromonal profiles and behavioral patterns. The researchers investigated the effects of taste and action by manipulating a gene that governs both the sex specificity of a fruit fly's body-surface hydrocarbons, or pheromones, and the sex-linked behavioral cues that issue through the dense nerve-cell network that constitutes the fly's brain.
"These findings underscore the importance of behavioral feedback in the manifestation of aggression," says Edward Kravitz, the George Packer Berry Professor of Neurobiology at Harvard Medical School.
The research is published in the November 23 issue of PLoS Biology.
Mara de la Paz Fernndez and Yick-Bun Chan, post-doctoral researchers in the Kravitz lab, discovered these links to aggression when investigating whether a male fruit fly would ever attack a female. They focused on a particular gene called transformer, which is active in females but not in males. Through blocking transformer expression in a variety of different tissues in females, the researchers could specifically alter the "femaleness" or "maleness" of the pheromones, which in turn altered the patterns of aggressive behavior encoded in the fly's brain.
When they changed pheromone profiles so that females "tasted" like males, the researchers found that males would attack them. This indicated that pheromonal cues alo
|Contact: David Cameron|
Harvard Medical School