[Public domain] via Wikimedia CommonsFruit flies (Drosophila melanogaster) rely heavily on their sense of smell, and a large portion of their brain is dedicated to processing olfactory information. Recently, a group directed by Grace Boekhoff-Falk (University of Wisconsin, Madison) determined that the gene distal-less (dll) is essential for correct development of this olfactory system in fruit flies (Proc. Natl. Acad. Sci. USA doi:10.1073/pnas.1016741109; published online 17 January 2012).