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Electroreception in the obligate freshwater stingray, Potamotrygon motoro

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Date Issued:
2013
Summary:
Elasmobranch fishes use electroreception to detect electric fields in the environment, particularly minute bioelectric fields produced by potential prey. A single elasmobranch family (Potamotrygonidae) is composed of obligate freshwater stingrays endemic to the Amazon River. A freshwater existence has imposed morphological adaptions on their electrosensory system due to life in a high impedance medium. Because their electrosensory morphology differs from their marine relatives, freshwater stingrays may demonstrate corresponding differences in behavioral sensitivity. The objective of this study was to quantify behavioral sensitivity of the obligate freshwater stingray Potamotrygon motoro to prey-simulating voltage. The voltage produced by common teleost prey of P. motoro were measured and replicated for behavioral trials. The best response was 10.62 cm, and the smallest voltage gradient detected was 0.005 mVcm-1. This sensitivity is reduced compared to marine species. The conductivity of the medium, more so than ampullary morphology, may dictate sensitivity of the elasmobranch electrosensory system.
Title: Electroreception in the obligate freshwater stingray, Potamotrygon motoro.
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Name(s): Harris, Lindsay L.
Charles E. Schmidt College of Science
Department of Biological Sciences
Type of Resource: text
Genre: Electronic Thesis Or Dissertation
Date Issued: 2013
Publisher: Florida Atlantic University
Physical Form: electronic
Extent: viii, 44 p. : ill. (some col.)
Language(s): English
Summary: Elasmobranch fishes use electroreception to detect electric fields in the environment, particularly minute bioelectric fields produced by potential prey. A single elasmobranch family (Potamotrygonidae) is composed of obligate freshwater stingrays endemic to the Amazon River. A freshwater existence has imposed morphological adaptions on their electrosensory system due to life in a high impedance medium. Because their electrosensory morphology differs from their marine relatives, freshwater stingrays may demonstrate corresponding differences in behavioral sensitivity. The objective of this study was to quantify behavioral sensitivity of the obligate freshwater stingray Potamotrygon motoro to prey-simulating voltage. The voltage produced by common teleost prey of P. motoro were measured and replicated for behavioral trials. The best response was 10.62 cm, and the smallest voltage gradient detected was 0.005 mVcm-1. This sensitivity is reduced compared to marine species. The conductivity of the medium, more so than ampullary morphology, may dictate sensitivity of the elasmobranch electrosensory system.
Identifier: 859865187 (oclc), 3362382 (digitool), FADT3362382 (IID), fau:4188 (fedora)
Note(s): by Lindsay L. Harris.
Thesis (M.S.)--Florida Atlantic University, 2013.
Includes bibliography.
Mode of access: World Wide Web.
System requirements: Adobe Reader.
Subject(s): Fishes -- Sense organs
FIshes -- Physiology
Stingrays -- Physiology
Fish culture
Persistent Link to This Record: http://purl.flvc.org/fcla/dt/3362382
Use and Reproduction: http://rightsstatements.org/vocab/InC/1.0/
Host Institution: FAU