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 an d the characteristics of potential mates to adjust their search behavior an d mate choices. We examined the effect of previous acoustic experience on f emale mating responses in the variable field cricket Gryllus lineaticeps. F emales of this species prefer calling songs with higher chirp rates to thos e with lower chirp rates. In this study we examined how female responses to male calling songs change with experience by measuring the responses of fe males 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 a nd final low chirp rate presentations, whereas females in group II showed a significantly reduced response to the final low chirp rate song. In additi on, the degree to which female responses to the initial and final low chirp rate song changed differed significantly between the treatment groups. Thu s acoustic experience appears to affect female mating preferences in this s pecies; exposure to either more attractive songs or more variable songs mak es normally unattractive songs even less attractive. These results suggest that females do not use a fixed-threshold search rule in which they mate wi th any male with a phenotype that exceeds a given threshold. Instead, G. li neaticeps females appear to use a more complex search rule in which they ad just their searching behavior based on the local distribution of male pheno types.