Abstract

Traits can only function together if expressed together, but the evolution of such phenotypic integration remains poorly understood. In this talk, I will present our recent work on the evolutionary origin and geographic spread of a sexually selected syndrome in wall lizards. Climatic effects on the strength of sexual selection causes a mosaic of phenotypic variation across the landscape, and promotes asymmetric introgression into a distantly related lineage. The phenotypic integration of color, morphology, and behavior persists throughout a hybrid zone, pointing towards a genetic architecture with a single or few major loci. Analyses of genomic data supports this hypothesis and reveals a single candidate region with striking structural variations. I discuss how this genomic architecture can orchestrate the co-expression of color, morphology, and behavior, and what it can teach us about the evolution of complex phenotypes.