Measuring sexual selection on females in sex-role-reversed Mormon crickets (Anabrus simplex, Orthoptera: Tettigoniidae)

Abstract

Although many studies examine the form of sexual selection in males, studies characterizing this selection in females remain sparse. Sexual selection on females is predicted for sex-role-reversed Mormon crickets, Anabrus simplex, where males are choosy of mates and nutrient-deprived females compete for matings and nutritious nuptial gifts. We used selection analyses to describe the strength and form of sexual selection on female morphology. There was no positive linear sexual selection on the female body size traits predicted to be associated with male preferences and female competition. Instead, we detected selection for decreasing head width and mandible length, with stabilizing selection as the dominant form of nonlinear selection. Additionally, we tested the validity of a commonly used instantaneous measure of mating success by comparing selection results with those determined using cumulative mating rate. The two fitness measures yielded similar patterns of selection, supporting the common sampling method comparing mated and unmated fractions. © 2010 The Authors. Journal Compilation © 2010 European Society For Evolutionary Biology.