Sex Determination in Green Turtle Hatchlings: Geometric Morphometry and Molecular Sex Markers

Year 2019, , 42 - 54, 31.01.2019

Bektaş Sönmez Efkan Bağda Onur Candan Hasan Emre Yilmaz

https://doi.org/10.28978/nesciences.522623

Cited By: 2

Abstract

Determination of the sex ratio in sea turtle population is one of the most important parameters for
the conservation and management of the species. We aimed to the test usability of the more than
one approaches that identify the sex of hatchlings with alternative non-invasive methods.
Geometric morphometry and molecular sex marker were used to indicate difference between the
sexes in the green sea turtle (Chelonia mydas) hatchlings which sexes were previously determined
by gonad histology. A total of 60 landmarks were identified from three body parts (carapace,
plastron and tail) for geometric morphometry. No sex specific difference was found in these three
body parts. Furthermore, we analyzed a total of 55 different oligonucleotide combinations using
sex-based pool strategy but found no difference. These two techniques are insufficient for sex
determination in the green turtle hatchlings. A relatively small number of the primer combinations
and male hatchlings used to identify sex of C. mydas appears to be a disadvantage. In order to
obtain clearer results with geometric morphometric and molecular sex markers, it is recommended
to compare sexes in laboratory conditions with constant temperature.

Keywords

Geometric morphometry, AFLP, Sex determination, Green Turtle, Samandağ, Sugözü Beaches

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