According to the Charnov-Bull model, for TSD to evolve, the same environmental conditions must influence male and female reproductive success fitness differently. Environmental conditions such as humidity or population density can alter sex in some organisms, and a widespread form of non-genetic sex determination is temperature-dependent sex determination.
In TSD of Jacky dragons, temperature can influence the development of sex in an embryo by regulating production of hormones responsible for the development of sex organs. A possible explanation may be that most reptile species feature homomorphic sex chromosomes [ 2 ], lending little support for the accumulation of deleterious mutations.
An alternative hypothesis of adaptive significance was proposed by Bulmer and Bull in  and supported by the work of Pen et al.
However, there is evidence that during climactic extremes, changes in the sex determining mechanism itself to GSD are selected for, particularly temperature dependent sex determination advantages of using the internet in Windsor the highly-mutable turtles.
Researchers have documented TSD in a wide range of species, and they continue to investigate how such a sex determining system has evolved. Developmental Dynamics. Charnier observed that temperature affected sex ratios, which are the number of females versus males in a population or a single clutch of eggs, of the rainbow Agama lizard, Agama agama.
Permissions Icon Permissions. Search Menu. To obtain the best experience, we recommend you use a more up to date browser or turn off compatibility mode in Internet Explorer. Whiteman Oecologia The sex with the reduced sex chromosome dies earlier: a comparison across the tree of life Zoe A.
Global Change Biology. TSD reveals how embryonic development can contribute to the evolution of physiological processes. Their study validated the Charnov-Bull model, showing that for some species and taxonomic groups, differential fitness may be a primary force in the evolution of TSD.
Retrieved April 16, — via ETI. Sources Bull, James. They conjectured that disruptive selection produced by variation in the environment could result in an evolutionary transition from ESD to GSD Bull, Vogt, and Bulmer,