Meeting Abstract
As predictions of higher temperatures loom on the horizon, many climate models also predict increased magnitude and frequency of extreme heat events. Species’ distribution, in part, depend on physiological tolerances and performance. Nocturnal rodents will increasingly be subject to warmer conditions, which may directly impact activity periods and their abilities to balance water and energy budgets. We examined the relative thermoregulatory capacities of members of a rodent community to assess the potential effects of a warmer environment on animal performance. Specifically, we measured the thermoregulatory function of Cricetid (N. albigula, N. lepida, P. eremicus, P, crintus) and Heteromyid rodents (D. merriami, C. formosus, and C. spinatus) at three sites in the Mojave Desert with differing average air temperatures. We used flow-through respirometry to measure resting metabolic rate (CO2 production) and evaporative water loss while continuously measuring body temperature over a wide range of air temperatures. We compared performance as a function of body size, taxonomy and site to examine the potential effects of warming and extreme events on relative animal function. Results suggest only small differences in RMR, EWL, and body temperature within species among sites.
