WINNE, C. T. *; KECK, M. B.: The Historical Evolution of Thermal Physiology in the Diamondback Watersnake, Nerodia rhombifer

We investigated three laboratory measures of thermal physiology in the diamondback watersnake, Nerodia rhombifer, along a latitudinal gradient spanning 12 degrees in latitude and including individuals from three populations in Southern Texas (26,^o 03’), one population in Central Texas (31,^o 45’), three populations in Central Oklahoma (35,^o 13’), and one population in Central Kansas (38,^o 03’). Preferred body temperature, temperature-specific metabolism, and critical thermal maximum were compared among the populations to determine whether or not intraspecific variation in these traits provided evidence of local adaptation to respective climate regimes. Using this historical approach we apply our results in the context of conservation, as an indicator of the probability that N. rhombifer may be able adapt to future global warming.