John True studies developmental and evolutionary genetics and works with Drosophila fruit flies to study the developmental genetics of adaptation and speciation (the process by which new species are formed). He is an expert in the genetics and development of insect pigmentation and has published over 30 papers in the areas of the genetics of new species formation and species differences in pigmentation, behavior, and morphology. This work helps establish the role of gene regulatory diversity in the origin and diversity of visible traits among species.