Meeting Abstract
Temperature can have wide-ranging and dramatic effects on poikilothermic animals across all levels of biological organization, from metabolism to interspecific interactions. Elevational gradients are a particularly interesting system in which to examine this, as temperatures can vary widely across different temporal and spatial scales. This study investigates how, across an elevational gradient, metabolic rates and critical thermal limits vary within and between sexes and species of jumping spiders in the genus Habronattus. Using a repeated measures design, we measured metabolic rate in males and females of six different species in the Santa Rita Mountains in Arizona: H. clypeatus, H. geronimoi, H. pugillis, H. conjunctus, H. hallani, and H. virgulatus. After collecting all animals and holding them at lab temperature (~22 °C) for at least 2 weeks we measured VCO2 produced using stop-flow respirometry techniques. Each individual was incubated at 7 different temperature treatments (from 10°-40°C, at 5 degree intervals). We also assessed CTmin and CTmax for each sex and species. We found several differences between sexes and species in their thermal physiology. We suggest that variation in thermally related physiology corresponds to their elevational range and is likely important in driving species distributions across the elevational gradient.
