Many data suggest an involvement of estrogens in gonadal differentiation in reptiles with
temperature-dependent sex determination (TSD). However, the site of estrogen synthesis in
two species of freshwater turtles is unclear. In Emys orbicularis, estrogens were shown to be
produced by the gonads, whereas in Trachemys scripta, gonadal steroids were not detected.
The marine turtle Dermochelys coriacea exhibits TSD but in gonadal development, ovarian
differentiation is delayed. Gonadal aromatase activity and estrogen content in this species …