Is plasticity in field cricket mating behaviour mediated by experience of song quality?

Many animals rely upon signals to discriminate among potential mates. Through mate choice, they may gain fitness advantages for themselves and their offspring and exert selection on signals and signallers. In some species, mating preferences are phenotypically plastic and mediated by experience of signals. Teleogryllus oceanicus, the Pacific field cricket, has been a productive model for studies of acoustically mediated phenotypic plasticity because many aspects of adult mating behaviour and reproductive physiology are differentially expressed when crickets develop in the presence versus absence of conspecific signals. An open question is whether the quality of conspecific signals experienced during development also mediates the mating preferences of adult females, as it does in some other animals. We tested the mating assurance in a variable environment hypothesis, which posits that adaptive plasticity in the expression of female mating preferences could protect females from costs associated with being too selective when preferred mates are rare or absent, while allowing selectivity when preferred mates are available. We experimentally manipulated the acoustic signals in the rearing environment as a reliable cue about the availability of preferred mates in the adult environment. Specifically, environments varied in the percentage of long chirp, a trait of male advertisement song known to be under precopulatory sexual selection. When subjects reached maturity, we used a within-subjects phonotaxis (movement towards sound) assay to measure female preferences for the percentage of long chirp. We replicated our experiment in populations from three islands of the Hawaiian Archipelago. We found evidence that some measures of female response are plastic and mediated by song quality, but effects were population specific and not entirely consistent with the predictions of the mating assurance in a variable environment hypothesis. Our results point to limited song quality-mediated plasticity in female mating preferences.