Meeting Abstract
Color polymorphism is the presence of two or more distinct, genetically determined color morphs within a single interbreeding population. An underexplored question in color polymorphic species pertains to how the phenotypes are maintained among populations. Little work has been done to examine geographic patterns in polymorphisms, with most studies focusing on a single population. Mechanisms that may maintain polymorphisms include negative frequency dependent selection, spatiotemporal variation in selection, and gene flow among populations. Investigating these mechanisms in multiple populations provides insight into the processes underlying the maintenance of genetic variation within and among populations. The Eastern Red-backed Salamander, Plethodon cinereus, is widespread throughout northeastern North America, and has two common color morphs. Previous studies have suggested that the two color morphs of P. cinereus differ in many elements of their biology, including physiology, territoriality, and mating interactions. However, most studies focus on a single biological feature in a single population, so little is known about diversifying selection, co-adapted gene complexes, or multivariate niche differentiation. In addition, the evolutionary processes that maintain the polymorphism in populations are not understood. Using microsatellite loci, this study aims to determine whether geographic distance or phenotype is more heavily correlated with genotypic divergence. Overall, this study provides critical information on the role of gene flow and natural selection in the evolution and maintenance of this color polymorphism, and links patterns of genetic differentiation with an understanding of the ecology of morph differences in P. cinereus.
