This is called temperature-dependent sex determination, or TSD. Cite this Page Gilbert SF. One of the best-studied reptiles is the European pond turtle, Emys obicularis.
As mentioned in Chapter 3, the sex of the echiuroid worm Bonellia depends on where a larva settles. Bibcode : Sci Synergism between temperature and hormones has also been identified in these systems. Although few previous studies had supported the theory in reptiles, Pieau proposed TSD as an alternative to genotypic sex determination.
A slightly different example of this temperature-induced sex reversal is found in an Australian dragon lizard, which has the ZW system of sex chromosomes. Estrogen can override temperature and induce ovarian differentiation even at masculinizing temperatures. If the larva is attracted to a female's proboscis, it travels along the tube until it enters the female's body.
After Coe This increase in aromatase enables individuals to develop into males or females depending on the temperatures experienced. Sunderland MA : Sinauer Associates ; Pieau and his colleagues focused on defining the TSD thermosensitive period, or the time of development during which changes in temperature can alter sexual organ growth.
An Introduction to Behavioral Endocrinology. Unlike the situation in mammals, sex determination in reptiles and birds is hormone-dependent.
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