AZIZI, E.*; LANDBERG, T.; BRAINERD, E.L.: Kinematics and Performance of the Escape Response in an Aquatic Salamander, Eurycea bislineata.

Despite the large body of information on the aquatic escape response of fishes, the kinematics and neurobiology of fast-starts in salamanders remain poorly understood. We examine the effect of ontogenetic changes in morphology on escape performance in larval and adult two-lined salamanders, Eurycea bislineata. The two life stages of this lungless stream salamander overlap in body size. Body length in our sample ranged from 4.8 to 6.4 cm in larvae and 5.8 to 7.5 cm in adults. At metamorphosis, these salamanders lose the tail fin which reduces the lateral profile in the caudal region of the adults. Analysis of cross-sections at various body positions reveals a decrease in the relative muscle mass of adults. We elicited escape responses using tactile stimuli directed at the forelimbs of E. bislineata. The observed kinematics, which consist of a preparatory and a propulsive phase, resemble the C-starts described for numerous fish species. The duration of stage 1 (C-forming phase) was found to increase with body length. Maximum body curvature (measured at the end of stage 1) varied between larval and adult salamanders. Because differences in relative muscle mass and lateral profile have been shown to effect escape performance in fish, we hypothesize that the observed morphological and kinematic variation in larval and adult E. bislineata will lead to differences in escape performance.