Meeting Abstract
The evolution and maintenance of color polymorphisms inferred to represent alternative mating tactics are most often studied within the framework of sexual selection theory. Indeed, morphs typically diverge in key factors tied to reproductive success such as social dominance, mate access, and territory quality. However, this emphasis limits our appreciation of the range of other parameters capable of influencing the evolution of color polymorphic systems. For example, in some lizards, heterogeneous morph spatial dispersion patterns occur that suggest a link between morph occupancy and local climatic regimes occurs as well. I capitalized on a long-term dataset on male ornate tree lizards (Urosaurus ornatus) to test the hypothesis that color morphs linked to alternative mating tactics also diverge in environmental tolerances. Males were scored visually as expressing one or two of the three putative color alleles (o, b, y), and climate data were obtained for each locality-year combination. My findings reveal allele-specific patterns of climate-mediated turnover over a seven-year period that are remarkably congruent with allele occupancy patterns across 56 localities spread through a broad portion of the species’ geographic range. Specifically, blue alleles were most strongly associated with wetter and cooler years/habitats, and orange alleles were more likely to occur in hotter and drier years/habitats. In contrast, yellow alleles exhibited no clear climate associations in either dataset. Collectively, these findings support that the underlying physiological differences among competing morphs influence their relative survival across an environmental gradient as well as their mating success. In a broader sense, the joint effects of these processes could serve to enhance a polymorphic species’ capacity to persist in lieu of environmental change.
