Meeting Abstract

54.2  Saturday, Jan. 5  Does body shape determine escape response performance in fishes? SWANSON, BO*; DIGIOVINE, CM; DORSEY, JP; ROSS, RN; Gonzaga University; Gonzaga University; Gonzaga University; Gonzaga University swansonb@gonzaga.edu

To survive, nearly all fishes must swim quickly to avoid predators, often using a stereotyped C-start escape response behavior. Fishes also demonstrate extreme diversity in body, fin, and muscle morphology, the structures biomechanically responsible for producing acceleration and thrust during this behavior. Several hypotheses have been suggested for how shape relates to performance, however comparative studies using multiple species have not shown consistent patterns or correlations between morphological and performance variables. Here we use kinematics and phylogenetically corrected statistics to test several of these hypotheses regarding the relationship between fish shape and escape response performance. We recorded high-speed digital video of 5 individuals of each of 20 different species of cichlid fish (Cichlidae) performing escape responses (over 1000 sequences). Acceleration, velocity, and timing variables were calculated from digitized image sequences. To assess shape variation, geometric morphometrics were used. These performance and shape data were mapped onto a phylogeny of the cichlids and standardized independent contrasts were calculated. These contrasts were used to test for evolutionary correlations between variables, estimate ancestral values, and test for phylogenetic inertia in both morphological and performance traits.