Sex Determination in Reptiles

@article{Bull1980SexDI,
  title={Sex Determination in Reptiles},
  author={James J. Bull},
  journal={The Quarterly Review of Biology},
  year={1980},
  volume={55},
  pages={3 - 21}
}
  • J. Bull
  • Published 1 March 1980
  • Biology
  • The Quarterly Review of Biology
Two factors in reptile sex determination have been studied: (1) the presence or absence of heteromorphic sex chromosomes, and (2) the influence of temperature. Recognizable sex chromosomes are common in snakes and lizards, but are apparently rare in turtles and absent in crocodilians and the tuatara. Temperature-dependent sex determination (TSD) is common in turtles and has been reported in two lizards and alligators; however, data on TSD are available for few non-turtle species. Present… 
Sex-determining mechanisms in squamate reptiles
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Environmental Sex Determination in Reptiles: Ecology, Evolution, and Experimental Design
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OF BIOLOGY JUNE 1991 ENVIRONMENTAL SEX DETERMINATION IN REPTILES : ECOLOGY , EVOLUTION , AND EXPERIMENTAL DESIGN
TLDR
Physiological investigations of TSD have clarified the roles of steroid hormones, various enzymes, and HY antigen in sexual differentiation, whereas molecular studies have identified several plausible candidates for sex-determining genes in species with TSD.
Are Reptiles Predisposed to Temperature- Dependent Sex Determination?
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Sex determination: Are two mechanisms better than one?
  • J. Bull
  • Biology
    Journal of Biosciences
  • 2008
TLDR
It is reported that, in the lab, extreme incubation temperatures can override sex chromosomes in the development of gonadal sex, and should be surprised at the coexistence of both systems in a species.
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