Meeting Abstract
The regulation of metabolism in response to environmental stressors is a crucial adaptation. Increased metabolic rate leads to mitochondrial production of reactive oxygen species. Here, we investigate the impact of metabolic rate on oxidative stress in the Common side-blotched lizard (Uta stansburiana) and compare sex differences in standard metabolic rate relative to oxidative stress. The metabolic rates of males and females may also differ significantly due to both differential energetic requirements and levels of metabolically active hormones. In this study, we measured resting metabolic rate and oxidative capacity in 53 male and 39 female wild-caught side-blotched lizards from St. George, UT. Oxidative capacity of individuals was calculated by combining measures of blood antioxidants (OXY) and reactive oxygen metabolites (d-ROMS). The oxidative index data were compared with standard metabolic measures of O2 intake and CO2 output in a climate-controlled environmental chamber. We also assessed the effect of reproductive investment (e.g., clutch size and stage) on oxidative capacity in females. From these comparisons we can better understand the sex-dependent role of physical stress on metabolism, as well as the oxidative costs of both reproductive investment and metabolic activity.
