One of the papers published in the special issue on “Mechanisms of Speciation” by the International Journal of Evolutionary Biology is a report on postmating, prezygotic reproductive isolation in the virilis group of Drosophila by Yasir Ahmed-Braimah (Orr Lab) and Bryant McAllister (University of Iowa). In it, they characterize the strong gametic incompatibility observed between a young species pair in the virilis phylad.