Meeting Abstract

31.6  Sunday, Jan. 5 09:15  Physiological and genomic underpinnings of cold tolerance variation in the green anole, Anolis carolinensis CAMPBELL-STATON, SC*; CHEVIRON, ZA; BARE, AC; LOSOS, JB; EDWARDS, SV; Harvard University; University of Illinois Urbana-Champaign; University of Illinois Urbana-Champaign; Harvard University; Harvard University scstaton@fas.harvard.edu

Climate can play an important role in the evolutionary history of species. Novel variation in the abiotic environment can limit species distributions and provide a selective pressure leading to adaptive differentiation between populations distributed across a climatically heterogeneous range. The green anole lizard, Anolis carolinensis, is an ideal species to explore the physiological and molecular basis of thermal adaptation. The only anole native to the continental United States, this species has spread throughout the southeast to occupy diverse thermal environments from subtropical peninsular Florida and southern Texas to temperate climate along the east coast, the foothills of the Smoky Mountains and Oklahoma. We measured the upper (CTmax) and lower (CTmin) boundaries of thermal tolerance of 15 populations across the species’ range and performed a common garden experiment to test if variation in thermal tolerance may have a genetic component. We then used double digest restriction-site associated digest sequencing (ddRAD-seq) to explore the relative effects of geographic distance and environmental dissimilarity in contributing to molecular variation across the species’ range. Finally, we used oxygen consumption and blood physiology data (hemoglobin and lactate concentrations) to explore the physiological mechanisms contributing to variation in cold tolerance. The results of this study will provide valuable information for understanding the evolution of thermal tolerance in terrestrial ectotherms.