Interspecific genetics of speciation phenotypes: song and preference coevolution in Hawaiian crickets

Understanding the genetic architecture of traits involved in premating isolation between recently diverged lineages can provide valuable insight regarding the mode and tempo of speciation. The repeated coevolution of male courtship song and female preference across the species radiation of Laupala crickets presents an unusual opportunity to compare the genetic basis of divergence across independent evolutionary histories. Previous studies of one pair of species revealed a polygenic basis (including a significant X chromosome contribution) to quantitative differences in male song and female acoustic preference. Here we studied interspecific crosses between two phenotypically less diverged species that represents a phylogenetically independent occurrence of intersexual signaling evolution. We found patterns consistent with an additive polygenic basis to differentiation in both song and preference (nE=5.3 and 5.1 genetic factors, respectively), and estimate a moderate contribution of the X...