Do cavefish larvae see their prey?

Abstract

Event Abstract Back to Event Do cavefish larvae see their prey? Amy Streets1 and Daphne Soares1* 1 University of Maryland, College Park, Department of Biology, United States The emergence of new species-specific behaviors is only possible due to the evolutionary malleability of neural circuits. In the tetra fish Astyanax mexicanus, we find a particularly good window into the adaptation of behavior during speciation. Currently, Astyanax is undergoing allopatric speciation and is extant in two forms: an ancestral, sighted river dwelling form and a derived, blind cave dwelling form. Although adult cavefish lack functional eyes, small eye primordia form during embryogenesis, but later arrest in development, degenerate, and sink into the orbit. Because the degeneration of the retina in the cavefish takes a few weeks posthatch, we hypothesized that these animals have a functional visual system as larvae. We used a visually guided prey catching assay to examine the level of performance of cavefish versus surface fish from one to two weeks of age. We tested animals in light and dark environments and after disruption of lateral lines. Hair cells were killed by exposure to an aminoglycoside antibiotic (gentamicin). Cavefish were able to hunt using vision alone at one week of age, but this ability was greatly reduced after two weeks. We examined the anatomy of the degenerating retina using transmission electron microscopy as well as the change in visual function by using electroretinograms. We also quantified neuromast number and distribution by using the fluorescent dye DASPEI. Our results show that the cavefish Astyanax mexicanus changes their sensory strategy for catching prey from an ancestral, visually guided one to a derived, mechanosensory approach when their retinas degenerate. Keywords: adaptation, Behavior, cavefish, Lateral Line, Vision Conference: Tenth International Congress of Neuroethology, College Park. Maryland USA, United States, 5 Aug - 10 Aug, 2012. Presentation Type: Poster (but consider for student poster award) Topic: Evolution Citation: Streets A and Soares D (2012). Do cavefish larvae see their prey?. Conference Abstract: Tenth International Congress of Neuroethology. doi: 10.3389/conf.fnbeh.2012.27.00058 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 03 May 2012; Published Online: 07 Jul 2012. * Correspondence: Dr. Daphne Soares, University of Maryland, College Park, Department of Biology, College Park, 20742, United States, daph@umd.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Amy Streets Daphne Soares Google Amy Streets Daphne Soares Google Scholar Amy Streets Daphne Soares PubMed Amy Streets Daphne Soares Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.