Temperature-dependent gonadal hybrid dysgenesis in Drosophila willistoni

Temperature-dependent gonadal dysgenesis was shown to occur in the progeny of both inter- and intrastrain Grosses involving two populations of Drosoph ila willistoni, one of which was an old laboratory stock, and the other, fr eshly collected from a natural population. We propose that the phenomenon o bserved was caused by the mobilization of transposable elements, as occurs in several other Drosophila species.