Modeling thermal influence on animal growth and sex determination in reptiles: being closer to the target gives new views.
Many species of oviparous reptiles, including crocodilians, a majority of turtles, some lizards and the 2 closely related species of Sphenodon have been shown to display temperature-dependent sex determination (TSD). Whereas it has been demonstrated very early that TSD also occurs in natural conditions, the relationship between a time series of changing temperatures and sex ratio remains a challenging problem for reptiles. We describe how a physiological model of embryo growth, gonadal development and aromatase activity can produce outputs that mimic well TSD. We provide an enhancement of a previously published model taking into account direct effect of temperature on aromatase activity. The comparison between the original model and the new one suggests that aromatase expression is controlled by a repressor factor expressed at masculinizing temperatures rather than its enhancement at feminizing temperatures.
Girondot
M
M
Laboratoire Ecologie, Systématique et Evolution (UMR8079), Faculté des Sciences d'Orsay, Université Paris-Sud, France. marc.girondot @ u-psud.fr
Ben Hassine
S
S
Sellos
C
C
Godfrey
M
M
Guillon
J-M
JM
D000818:Animals; D005260:Female; D008297:Male; D008954:Models, Biological; D012104:Reptiles / Q000254:growth & development* / Q000502:physiology*; D019849:Sex Determination Processes; D012744:Sex Ratio; D013696:Temperature