DISSERTATION RESEARCH: Ecological and Evolutionary Significance of Locomotor Performance in Collared Lizards (Crotaphytus collaris)

Oklahoma State University, Stillwater OK

Investigators

Abstract

Ecological and evolutionary significance of locomotor performance in collared lizards (Crotaphytus collaris) Stanley F. Fox and Jerry F. Husak The evolution of morphological and physiological traits has, in large part, been examined by studying the performance of whole animals, mostly in the laboratory. Although most scientists agree that morphology affects performance, then performance affects an individual's ability to survive and reproduce (fitness), no study has shown how all three elements--morphology, performance, and fitness--are linked. More importantly, little is known about how or when maximal performance may be used. How often is laboratory-measured maximal performance used in nature, and in what ecological contexts? This study addresses this deficiency for the first time by determining how performance affects fitness in a territorial lizard species, while simultaneously considering alternative hypotheses. Data on maximal sprint speed, field-realized sprint speed, hormone levels, social behavior, and mating success in collared lizards will reveal to what degree each contributes to the fitness of males and females, and test how natural and sexual selection (natural selection on traits that improve mating success) may act differentially on performance. The intellectual merit will be a better understanding of how selection is acting on performance and the morphological and physiological traits that constrain it. The broader impact of this investigation is the training of undergraduates in research techniques.