Spatial dynamics of alternative reproductive strategies

Quantitative genetic models have recently demonstrated the dramatic influence social environments have on phenotypic evolution. Social environments are inherently dynamic, changing depending on the frequency and outcomes of conspecific interactions; they can be simultaneously, the targets and agents of selection. Understanding how organism modify their social environments, in order to maximize reproductive success is vital to our understanding of the selective forces at work in wild populations. From an intensive behavioral and ecological study of territoriality in the polymorphic white-throated sparrow, I demonstrate how the two morphs construct social niches in order to maximize their alternative reproductive strategies. By integrating techniques from molecular ecology, raster data analysis, and Geographic Information Science, I generated continuous, socio-spatial models of cuckoldry risk and local conspecific density. My results indicate that the morphs segregate their territories based on socio-spatial variables, creating a social landscape that is spatially heterogeneous and temporally stable. My findings also reveal that the nests of white and tan females are located in different social environments with possible consequences for extra pair paternity. Socio-spatial factors, similar to those seen in white-throated sparrows, may also play important roles in the evolution of mating systems in species with more continuous genotypic, morphological, and behavioral differences.