Meeting Abstract
21.4 Jan. 5 Does the thermal tolerance of the Western Fence Lizard change with air temperature? MCMILLAN, D.M.*; ADOLPH, S.C.; IRSCHICK, D.J.; University of Massachusetts Amherst; Harvey Mudd College; University of Massachusetts Amherst mcmillan@nsm.umass.edu
Understanding the effects of global climate change on populations of natural organisms is a difficult task because often the differences caused by changes in the climate can be subtle, and detecting these differences requires data over long time periods. One predicted outcome of global climate change is that the number of days of extreme temperatures in a given environment may increase even if the overall mean temperature does not. One measure of an organism�s ability to withstand extremely warm temperature is the Critical Thermal Maximum (CTmax). The CTmax is defined as the temperature above which an animal loses voluntary muscle control. For this study we measured the CTmax of the western fence lizard Sceloporous occidentalis, collected in the San Gabriel Mountains of California first in 1983 and then again in 2006. With this study we address the question; Does a shift in the thermal profile of the local habitat lead to a change in the way these animals withstand periods of extreme temperature? Our work points toward new ways of integrating the thermal physiology of animals with information on global climate change.
