Males adjust signaling effort based on female mate-preference cues

Female behavior involved in the expression of mate preferences often entails the production of cues that males may use to adjust their efforts and tactics, thus generating interactive back–and–forth reproductive dynamics. We investigated whether female duetting behavior in Enchenopa treehoppers (Hemiptera: Membracidae) offers cues about how attractive females find signaling males and whether males modify their signaling behavior accordingly. Playback experiments with females of 4 Enchenopa species showed that stimulus attractiveness influenced the likelihood, duration, and dominant frequency of female signals. A separate playback experiment with males of 1 of the 4 species showed that they modified their behavior according to the features of female duetting signals: Males were more likely to signal and to produce more signals when presented with longer female signals of intermediate frequency. Because the female signals evoking the greatest male response did not correspond to conspecific signals, we conclude that males have been selected to attend to cues indicating likely female receptivity but not species identity. We discuss the consequences of these findings for assortative mating and reproductive isolation.