Edward Kravitz

Aggression is a nearly universal feature of the behavior of social animals. In the wild, it is used for access to food and shelter, for protection from predation and for selection of mates. Despite its importance, little is known of the neural mechanisms that underlie the behavior. Although not well known, fighting behavior exists in common laboratory strains of the fruit fly, Drosophila melanogaster. With the genome sequenced and a wealth of powerful genetic tools available, fruit flies serve as a unique experimental model for the study of aggression. A simple experimental protocol developed in our laboratory allows reliable fighting behavior to be seen between pairs of male and pairs of female flies. The following recent results have been obtained using this system: (i) a quantitative analysis of fighting behavior in male and female flies has been performed; (ii) experiments have been completed demonstrating that learning and memory and changes in gene expression accompany changes in social status; (iii) genetic studies have shown that the same gene (fruitless) specifies who flies court and how they fight; and (iv) a group of 3 neurons expressing male forms of the fruitless gene and the amine octopamine are important in the choice between courtship and aggression in male fruit flies. Current studies continue these lines of investigation and are moving in the direction of mapping and manipulating the brain circuitry important in aggression and courtship behavior.