Hormone-mediated nutritional control of sexual behavior in male dung flies.

Male Scatophaga stercoraria must prey on other Diptera before they display sexual behavior, develop the accessory cells of their ejaculatory ducts, and achieve full elongation of the testes. The corpus allatum also becomes enlarged after predation and is necessary for the onset of sexual behavior and development of reproductive organs. The complex diet consumed during predation apparently activates the corpus allatum, and the hormone released acts independently on organ growth and sexual behavior.