Mating structure, the number and identity of a female's mates, is a central parameter in sex ratio theory. Despite this importance, mating structures have received little attention: empirical work has focussed on testing the predictions of theory rather than the underlying assumptions. Parasitoid Hymenoptera have control of progeny sex ratios and have been important to the development and testing of sex ratio theory. Empirical assessment of parasitoid mating structures, and their relation to observed sex ratios, is lacking and urgently required. This is particularly the case in polyembryonic parasitoids (multiple offspring develop from a single egg) in which non-sibling mating causes parent-offspring and intersexual offspring-offspring conflicts over the sex ratio.
I will relate mating structure to sex ratio conflicts in the polyembryonic parasitoid Copidosoma sosares. I will combine behavioural observations with newly developed molecular genetic techniques to obtain reliable estimates of mating structure. Empirical work will be carried out in both the laboratory and the field.