Meeting Abstract

P3.150  Monday, Jan. 6 15:30  Terrestrial jumping performance differs among genetically isolated populations of mangrove rivulus, Kryptolebias marmoratus ASHLEY-ROSS, M.A.*; PERLMAN, B.M.; GIBB, A.C.; EARLEY, R.L.; Wake Forest University; Wake Forest University; Northern Arizona University; University of Alabama rossma@wfu.edu

Kryptolebias marmoratus (Cyprinodontiformes) is distributed from the Atlantic coast of central Florida throughout the Caribbean as far as southern Brazil. It is notable for (1) making regular excursions onto land as part of its life history, and (2) being one of only two vertebrate species known to consist primarily of self-fertilizing hermaphrodites. We asked whether populations of K. marmoratus that are both geographically and genetically isolated from one another differ in terrestrial jumping performance. Six genetic lineages originally collected from three sites in Florida and three in the Caribbean (mainland Honduras, Belize, and Roatan Island) and maintained for multiple generations in the lab were assayed, thus ensuring that any differences observed would be attributable solely to genetics. Eight individuals per lineage were, one at a time, placed on a damp substrate inside a shallow wading pool, and observed without disturbance for two minutes, followed by 30 seconds in which the fish were repeatedly approached in order to elicit a maximal jump. Trials were recorded from above by a video camera (60 fps). The following measurements were made by analysis of the video using ImageJ: number of jumps, latency to first jump, average and maximum jump distance, angular trajectory of the jump, and total and net distances moved during the voluntary trial. Principal component analysis revealed that populations differed significantly in jump performance, with Florida populations having a higher propensity to jump, and longer jumps, than Caribbean populations. K. marmoratus may thus serve as a model system in which to examine the genetic basis of locomotor performance.