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Seafinding by the green turtle, Chelonia mydas: the orientation response is tuned to the lighting environment at the nesting beach
- Date Issued:
- 2018
- Abstract/Description:
- Hatchling marine turtles use visual cues to orient from their nest to the sea at night. However, the wavelengths of light that carry this information have not been properly documented, nor do we understand why they are favored. I measured wavelength irradiance at 20 nm intervals between 340 – 600 nm at a dark nesting beach and then, in the laboratory, determined the thresholds of the hatchlings for each λ that evoked a positive phototaxis. In this study, I show that green turtle hatchlings are (i) most sensitive to the shorter (360 – 480 nm) light wavelengths. Those light energies (ii) dominated the available natural lighting at the nesting beach. They also (iii) presented a steep gradient in irradiance between a landward and seaward view, an important cue for orientation. I attribute the phototactic responses to “stimulus filtering”, the outcome of natural selection that optimizes behavioral responses (seafinding) according to their function, as well as when and where they occur.
Title: | Seafinding by the green turtle, Chelonia mydas: the orientation response is tuned to the lighting environment at the nesting beach. |
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Name(s): |
Celano, Lisa, author Salmon, Michael, Thesis advisor Florida Atlantic University, Degree grantor Charles E. Schmidt College of Science Department of Biological Sciences |
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Type of Resource: | text | |
Genre: | Electronic Thesis Or Dissertation | |
Date Created: | 2018 | |
Date Issued: | 2018 | |
Publisher: | Florida Atlantic University | |
Place of Publication: | Boca Raton, Fla. | |
Physical Form: | application/pdf | |
Extent: | 43 p. | |
Language(s): | English | |
Abstract/Description: | Hatchling marine turtles use visual cues to orient from their nest to the sea at night. However, the wavelengths of light that carry this information have not been properly documented, nor do we understand why they are favored. I measured wavelength irradiance at 20 nm intervals between 340 – 600 nm at a dark nesting beach and then, in the laboratory, determined the thresholds of the hatchlings for each λ that evoked a positive phototaxis. In this study, I show that green turtle hatchlings are (i) most sensitive to the shorter (360 – 480 nm) light wavelengths. Those light energies (ii) dominated the available natural lighting at the nesting beach. They also (iii) presented a steep gradient in irradiance between a landward and seaward view, an important cue for orientation. I attribute the phototactic responses to “stimulus filtering”, the outcome of natural selection that optimizes behavioral responses (seafinding) according to their function, as well as when and where they occur. | |
Identifier: | FA00013034 (IID) | |
Degree granted: | Thesis (M.S.)--Florida Atlantic University, 2018. | |
Collection: | FAU Electronic Theses and Dissertations Collection | |
Note(s): | Includes bibliography. | |
Subject(s): |
Green turtle Chelonia mydas Phototaxis |
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Held by: | Florida Atlantic University Libraries | |
Sublocation: | Digital Library | |
Persistent Link to This Record: | http://purl.flvc.org/fau/fd/FA00013034 | |
Use and Reproduction: | Copyright © is held by the author, with permission granted to Florida Atlantic University to digitize, archive and distribute this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder. | |
Use and Reproduction: | http://rightsstatements.org/vocab/InC/1.0/ | |
Host Institution: | FAU | |
Is Part of Series: | Florida Atlantic University Digital Library Collections. |