Any mechanism of sex determination (q.v.) in which the sex of an organism is permanently established not by its genetic constitution, but by environmental conditions (such as temperature, local hormonal concentrations, or population density) in which it develops. For example, sex is determined in turtles and crocodiles by the prevailing temperature during the incubation of the fertilized eggs. Compare with genotypic sex determination.
Subjects: Genetics and Genomics.