Meeting Abstract
Rising ambient temperatures pose a novel threat to herbivorous mammals. Higher temperatures interact with mammalian physiology in such a way that poisonous compounds, like dietary plant toxins these mammals face at every meal, become more potent. This phenomenon is known as temperature-dependent toxicity (TDT). While the mechanism and effects of TDT have been previously investigated, it remains unknown whether mammalian herbivores would be able to mitigate the negative impacts of TDT by using cooler refugia in their natural environment. We investigated the use of cooler microclimates with a population of desert woodrats (Neotoma lepida) that inhabit the Mojave Desert and feed on creosote bush (Larrea tridentata). We predicted that woodrats would use cooler microclimates when provided access, and would show improved performance compared to woodrats without microclimate access. The effect of dietary creosote toxins on microclimate use and the influence of microclimate access on food intake and body mass maintenance were determined in a laboratory-based experiment. Woodrats did utilize cooler microclimates when provided access, but dietary creosote toxins did not appear to alter the behavior of the woodrats. Access to cooler microclimates did not affect food intake but did result in better defense of body mass compared to woodrats without microclimate access. These results suggest that cooler microclimates could provide a means to mitigate TDT through improved maintenance of body mass loss. More analysis is needed to better understand how woodrats use cooler microclimates. Understanding how mammalian herbivores interact with their environment is imperative to advance the field of plant-herbivore interactions as well as for management policies, especially during a period of climate change.
