Meeting Abstract

32.4  Wednesday, Jan. 5  Dimorphic feeding kinematics in an ancestral threespine stickleback population MCGEE, M.D.; Univ. of California, Davis mcgee@ucdavis.edu

Fish feeding kinematics generally show little sexual dimorphism, but it exists in some species and may increase their potential for rapid adaptation and speciation. I examined the feeding kinematics of anadromous threespine stickleback, Gasterosteus aculeatus, an ancestral phenotype thought to have given rise to ecologically divergent freshwater populations in the North Pacific. I collected adult anadromous stickleback from a Northern California population and used high speed video to record the feeding kinematics of stickleback consuming cladoceran prey. The fish were then cleared and stained, and I measured morphological traits linked to feeding. Stickleback that displayed male breeding colors exhibited different kinematic patterns than stickleback that displayed female coloration. I then examined morphological correlates of kinematic traits and discuss sexual dimorphism in kinematics and morphology from an ecological perspective. Within-species variation in anadromous stickleback is then compared to between-species variation in the adaptive radiation of freshwater sticklebacks from Alaska and British Columbia.