Sex Ratio and Mating Structure in the Parasitoid Hymenoptera

Assumptions about mating structure have been important in the development of sex ratio theory. Fisher's theory of frequency dependent selection for sex ratio equality, and Charnov's theory of sex allocation when host quality varies, assume panmixis, whereas Hamilton's theory of local mate competition assumes mating occurs only at the natal patch. An important group of organisms in stimulating the development of sex ratio theory, and in its empirical testing, have been the parasitoid Hymenoptera. These exhibit many life history variations and possess a mechanism by which females can adaptively control their progeny sex ratio. Although many parasitoid species may conform closely to both the assumptions and predictions of the above models, others do not