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Delimitation of the embryonic thermosensitive period for sex determination using an embryo growth model reveals a potential bias for sex ratio prediction in turtles.

Authors :
Girondot M
Monsinjon J
Guillon JM
Source :
Journal of thermal biology [J Therm Biol] 2018 Apr; Vol. 73, pp. 32-40. Date of Electronic Publication: 2018 Feb 10.
Publication Year :
2018

Abstract

The sexual phenotype of the gonad is dependent on incubation temperature in many turtles, all crocodilians, and some lepidosaurians. At hatching, identification of sexual phenotype is impossible without sacrificing the neonates. For this reason, a general method to infer sexual phenotype from incubation temperatures is needed. Temperature influences sex determination during a specific period of the embryonic development, starting when the gonad begins to form. At constant incubation temperatures, this thermosensitive period for sex determination (TSP) is located at the middle third of incubation duration (MTID). When temperature fluctuates, the position of the thermosensitive period for sex determination can be shifted from the MTID because embryo growth is affected by temperature. A method is proposed to locate the thermosensitive period for sex determination based on modelling the embryo growth, allowing its precise identification from a natural regime of temperatures. Results from natural nests and simulations show that the approximation of the thermosensitive period for sex determination to the middle third of incubation duration may create a quasi-systematic bias to lower temperatures when computing the average incubation temperature during this period and thus a male-bias for sex ratio estimate.<br /> (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Details

Language :
English
ISSN :
0306-4565
Volume :
73
Database :
MEDLINE
Journal :
Journal of thermal biology
Publication Type :
Academic Journal
Accession number :
29549989
Full Text :
https://doi.org/10.1016/j.jtherbio.2018.02.006