Asymmetric song responses in coexisting Japanese cicadas

Diel partitioning of singing, which has been observed from the tropics to the temperate regions, is among the various mechanisms of sound partitioning found in multispecies cicada assemblages and is regarded as an important mechanism of coexistence. Using playback experiments, we studied interspecific interference between two Japanese cicadas, Cryptotympana facialis and Graptopsaltria nigrofuscata, which exhibit similar peak frequencies in their calling songs and different diel patterns of song activity. We found that the males of the two species had different song response patterns: C. facialis responded significantly more to conspecific calling songs than G. nigrofuscata. These results suggest that male C. facialis have evolved more intense conspecific song recognition than G. nigrofuscata. This may cause male G. nigrofuscata to avoid destructive acoustic interference during their active singing time.