Meeting Abstract

76.3  Sunday, Jan. 6  Citius, altius, fortius: jumping kinematics and kinetics in two distantly related teleosts PERLMAN, BM*; KAWANO, S; BLOB, RW; ASHLEY-ROSS, MA; Wake Forest University; Clemson University; Clemson University; Wake Forest University

Many fish stranded on land will use axial movements to generate C-jumps in efforts to return to water. However, mangrove rivulus, Kryptolebias marmoratus (Cyprinodontiformes), generate coordinated jumps on land using a tail flip to locate new food resources, avoid predators, escape poor water conditions, or return to water. How do the mechanics of such directed jumps differ from those of typical stranded fishes? We quantified and compared the ground reaction forces (GRF) generated during directed jumps by K. marmoratus with those produced by similarly-sized largemouth bass, Micropterus salmoides (Perciformes), performing typical jumps of stranded fishes. Individual specimens were placed on a force platform that recorded the GRF in three dimensions (fore-aft, mediolateral, and vertical). Forces were normalized to the body weight of each animal. Two Phantom high-speed video cameras recorded the duration of the jump (from initial movement to launching off the force platform) and the jump trajectory with respect to the ground. Horizontal forces were greatest for K. marmoratus with peak GRF occurring at ~75% through the jump. M. salmoides had the greatest vertical GRF, occurring at ~60% of the jump. The trajectory of the bass C-jump was ~90° with respect to the ground compared to lower jump trajectories in K. marmoratus, leading to greater horizontal displacement in the latter. M. salmoides had faster jump durations (~40 ms to reach maximum body curvature), whereas K. marmoratus reached maximum body curvature at ~75 ms. While the jumps of M. salmoides strongly resemble aquatic fast starts, differences in force production and motion trajectory in K. marmoratus may indicate the use of different motor patterns to increase duration (and thus impulse) of the jump.