Results of Consecutive Matings of Female Anopheles gambiae Species B with Fertile and Sterile Males

THE Anopheles gambiae complex consists of five closely related species; two salt water ones, A. melas and A. merus, and three fresh water ones, provisionally designated A, B and C. When males from species A or B are crossed with females of A. melas or A. merus the F1 generation consists almost entirely of sterile males. It has been proposed that the release of such sterile males be used to control members of this species complex1. It has already been established that these males compete successfully against normal males when both are caged together with virgin females1. I have carried out experiments to investigate whether a female, once mated with a sterile male, could lay fertile eggs if she subsequently mated with a fertile male, or if a female, once mated with a fertile male, could be sterilized by mating with a sterile male. Previous authors, seeking evidence of multiple insemination in Anopheles spp. with the aid of marker genes, found very little indication of it2,3.