The Drosophila pheromone cVA activates a sexually dimorphic neural circuit

Despite marked behavioural differences between the sexes, surprisingly few anatomic features have been observed that differentiate the male and female brain in any species. But this study unveils a sexual dimorphism in the neuronal circuit responding to a pheromone, which induces different courtship behaviours in male and female fruitflies. The single neuron tracing technique that has been developed to do so should be useful to study the nervous systems of other genetically tractable species.