Temperature of egg incubation determines sex in Alligator mississippiensis
@article{Ferguson1982TemperatureOE, title={Temperature of egg incubation determines sex in Alligator mississippiensis}, author={Mark W. J. Ferguson and Ted Joanen}, journal={Nature}, year={1982}, volume={296}, pages={850-853} }
The factors controlling sexual differentiation in crocodilians are unknown, but heteromorphic sex chromosomes are absent from all species1. Nichols and Chabreck2 speculated that the sex of Alligator mississippiensis was not rigidly determined at the time of hatching but could be influenced by the post-hatching environment. They presented little evidence to support their hypothesis3 (no histological sections of hatchling gonads, no indication of the sex ratio at hatching), and their study failed…
342 Citations
Temperature‐dependent sex determination in Alligator mississippiensis
- Environmental Science, Biology
- 2009
The structure of the reproductive systems of hatchling and 1 -year-old alligators was investigated macroscopically and histologically and revealed that heavy females become sexually mature ahead of either light females or light males, which constitutes a selective biological advantage for the evolution of temperature-dependent sex determination in Alligator mississippiensis.
The mechanism of temperature dependent sex determination in crocodilians: a hypothesis
- Biology, Environmental Science
- 1989
The hypothesis is used to explain the late temperature sensitive periods defined by high to low temperature shift experiments, why cooler temperatures are more effective at determining sex, how intermediate temperatures can produce both sexes, and geographical similarities in the pattern of TSD within crocodilians despite differing climates.
Environmental regulation of sex determination in reptiles.
- BiologyPhilosophical transactions of the Royal Society of London. Series B, Biological sciences
- 1988
The phylogenetic implications of TSD for crocodilians, and reptiles in particular, are related to the life history of the animal from conception to sexual maturity, and those animals that develop under optimal conditions grow fastest and largest and become male.
Effects of Incubation Temperature on Crocodiles and the Evolution of Reptilian Oviparity
- Biology
- 1989
Crocodylus porosus is a mound-nesting crocodilian in which incubation temperature influences the rate of embryonic development, the probability that embryos will survive to hatching, post-hatching…
Temperature-Dependent Sex Determination and Artificial Incubation of Tuatara, Sphenodon Punctatus
- Environmental Science, Biology
- 2001
The evaluation of artificial incubation as a conservation management tool demonstrated that it is a procedure that benefits conservation as it can be used reliably to produce founders; hatching success was 94% during this study.
Temperature‐Dependent Sex Determination in Gekko japonicus (Gekkonidae, Reptilia)
- Environmental Science
- 1985
The effects of temperature on sexual differentiation in early development of the gekkonid lizard, Gekko japonicus were studied and the sex ratios do not seem to be related to a predetermination of sex with a differential mortality.
Incubation temperatures, sex ratios and sex determination in a population of Nile crocodiles (Crocodylus niloticus)
- Environmental Science
- 1987
A demographic study of the Nile crocodile Crocodylus niloticus at Lake Ngezi, Zimbabwe, revealed that females predominated in all size classes and among embryos. The sex of C. niloticus was shown to…
Influence of temperature variation on incubation period, hatching success, sex ratio, and phenotypes in Caiman latirostris.
- Environmental ScienceJournal of experimental zoology. Part A, Ecological and integrative physiology
- 2019
A masculinizing effect is found when incubation was at 31 ± 2°C compared with a constant 31°C; and temperature fluctuations at 32°C had a negative effect on hatchlings size and mass, and hatching success compared with constant incubation temperatures of32°C and 33°C.
Alternative life-history styles in reptiles
- Biology
- 1989
Analysis of the effects of size and phylogeny on patterns of co-variation in certain squamate life-history traits reveals that although many variables scale allometrically with body size, significant variation in clutch size and age at maturity remains at order, family and generic level.
Gonadal sex differentiation in Alligator mississippiensis, a species with temperature-dependent sex determination
- BiologyCell and Tissue Research
- 2004
Ovarian formation in alligators may depend upon presumptive Sertoli cells differentiating prior to a critical event in embryogenesis, such as germ cell proliferation and meiosis, as at lower incubation temperatures.
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