Meeting Abstract

P2.185  Thursday, Jan. 5  Jumping Kinematics in the Plethodontidae II: the effects of tail loss HESSEL, Anthony L.*; RYERSON, William; WHITENACK, Lisa B.; Allegheny College; University of Connecticut; Allegheny College hessela@allegheny.edu

Many defense mechanisms exist in the tool belts of the Plethodontidae family. At least 6 species of these lungless salamanders are capable of attaining vertical height when threatened, and it has been thought that the tail may play a role in the salamander’s specialized C-start jump while also keeping it stabilized in the unloading and mid-air phase. We ran jumping trials on 5 species of Plethodontidae with and without tails at 500 frames per second. The salamanders were placed on a platform and then approached from behind to simulate a predatory attack. This persuaded the salamanders to jump over a 5cm gap to a second, lower platform. Variables measured were bending angles, durations, and velocities, as well as jump height. Our preliminary results indicate no significant differences in the jumping abilities between tailed and de-tailed individuals within each species. Some variables that fall into the initiation of the jumps did have significant P-values, such as the max bed angles of Desmognathus ochrophaeus (P=.078) and Plethodon glutinosus (P=.04) during C-start. Removing tails represented a large loss of mass (mean mass loss: 27%, mean length loss: 48%), but they are not gaining more height from their jump than when they had their tails. It is possible that the tail could help stabilize and anchor hind limbs so that no energy is lost to slippage. Tail loss may not play a role in mid-air jumping, since tail loss does not change mid-air characteristics.