It appears that the enzyme aromatase which can convert testosterone into estrogen is important in temperaturedependent sex determination. Get smart. It is used in reference to species with temperature-dependent sex determination, such as crocodilians and turtles.
Temperature-dependent sex determination in three reptile species: the American alligator Alligator mississippiensisthe red-eared slider turtle Trachemys scripta elegansand the alligator snapping turtle Macroclemys temminckii.
Shoemaker CM, Crews D Analyzing the coordinated gene network underlying temperature-dependent sex determination in reptiles. Nature has provided many variations on her masterpiece. When two species of turtles were raised at female-promoting temperatures, Sox9 expression was down-regulated during the critical time for sex determination.
Ohno, Susumu. Zaborski P Temperature and estrogen dependent changes of sex phenotype and HY antigen expression in gonads of a newt. Personalised recommendations.
However, in the bipotential gonads of those turtles raised at male-promoting temperatures, Sox9 expression was retained in the medullary sex cords destined to become Sertoli cells Spotila et al. Turn recording back on. Moreover, the sensitive time for the effects of estrogens and their inhibitors coincides with the time when sex determination usually occurs Bull et al.
However, once an individual becomes female, it will not revert to being male Coe 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. In this species, individuals pile up on top of one another to form a mound Figure
The turtles were incubated at temperatures that produce solely males, both sexes, and solely females. 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.
Therein it differentiates into a minute 1—3-mm-long male that is essentially a sperm-producing symbiont of the female see Figure 3. Spencer and Janzen found that hatchlings from mixed-sex nests were less energy efficient and grew less than their same-sex counterparts incubated in single-sex producing temperatures.
Bibcode : Natur.