Meeting Abstract

S9-1.2  Monday, Jan. 7  Interactions between temperature and oxygen and the evolution of body size in invertebrates KLOK, CJ*; HARRISON, JF; Arizona State University; Arizona State University cjklok@asu.edu

Temperature is a key factor that affects the rates of growth and development in animals, which ultimately determine body size. While not universal, a widely documented and poorly understood pattern is the inverse relationship between temperature and body size. Among ectotherms, higher temperatures exponentially increase the rate of oxygen consumption over some ranges, while having minimal effects on gas diffusion. This effect forms one basis to the MASROS hypothesis (maintain aerobic scope – regulate oxygen supply – Atkinson et al. ’06) which states that growth and/or development rates will be altered to maintain maximal aerobic scope. The MASROS hypothesis remains one of the prominent explanations for the smaller body size of ectotherms reared at higher temperatures. To test the MASROS hypothesis, we utilize meta-analysis approaches to examine whether the response of an ecothermic species to temperature is associated with sensitivity to oxygen, phylogeny, gas exchange system, flight, or habitat, and how that interacts with other selection regimes that influence body size, eg. sexual selection or anti-predator selection. This research was partially supported by NSF IOS 1122157 to JFH and CJK.