Sexual selection and speciation in field crickets

Recent theoretical work has shown that sexual selection may cause speciatio n under a much wider range of conditions than previously supposed. There ar e, however, no empirical studies capable of simultaneously evaluating sever al key predictions that contrast this with other speciation models. We pres ent data on male pulse rates and female phonotactic responses to pulse rate s for the field cricket Gryllus texensis; pulse rate is the key feature dis tinguishing G. texensis from its cryptic sister species G. rubens. We show (i) genetic: Variation in male song and in female preference for song, (ii) a genetic correlation between the male trait and the female preference, an d (iii) no character displacement in male song, female song recognition, fe male species-level song discrimination, or female song preference. Combined with previous work demonstrating a lack of hybrid inviability, these resul ts suggest that divergent sexual selection may have caused speciation betwe en these taxa.