Meeting Abstract

P2.123  Wednesday, Jan. 5  Comparative startle responses of Astyanax mexicanus SWARTZ, A*; SOARES, DS; University of Maryland daphne.soares@gmail.com

The extreme environment of subterranean caves presents an adaptive challenge to troglobitic organisms. The mechanism by which natural selection modifies an ancestral surface neural circuit to produce a novel subterranean behavior remains a mystery. To examine this question we have performed comparative behavioral studies on various forms of the cave adapted teleost Astyanax mexicanus. This species provides a unique opportunity for comparative studies as it consists of an extant epigean (surface fish) and various different populations of eyeless, hypogean forms (cavefish). We filmed fishes using a high speed camera and quantified the components of the first phase of the fast startle response.