Experience affects female responses to male song in the variable field cricket Gryllus lineaticeps (Orthoptera, Gryllidae)

Search theory predicts that females will use information on search costs and the characteristics of potential mates to adjust their search behavior and mate choices. We examined the effect of previous acoustic experience on female mating responses in the variable field cricket Gryllus lineaticeps. Females of this species prefer calling songs with higher chirp rates to those with lower chirp rates. In this study we examined how female responses to male calling songs change with experience by measuring the responses of females to male calls over a sequence of three trials. Females in one group (group I) were exposed to a sequence of three identical low chirp rate songs and females in a second group (group II) were exposed to two identical low chirp rate songs interspersed by a high chirp rate song. Females in group I did not show a significant difference in their responses to the initial and final low chirp rate presentations, whereas females in group II showed a significantly reduced response to the final low chirp rate song. In addition, the degree to which female responses to the initial and final low chirp rate song changed differed significantly between the treatment groups. Thus acoustic experience appears to affect female mating preferences in this species; exposure to either more attractive songs or more variable songs makes normally unattractive songs even less attractive. These results suggest that females do not use a fixed-threshold search rule in which they mate with any male with a phenotype that exceeds a given threshold. Instead, G. lineaticeps females appear to use a more complex search rule in which they adjust their searching behavior based on the local distribution of male phenotypes.