Unlike the situation in mammals, sex determination in reptiles and birds is hormone-dependent. Spencer and Janzen found further support for the Charnov-Bull model by incubating painted turtles Chrysemys picta at different temperatures and measuring various characteristics indicative of fitness.
Some other conditions, e.
Head, G. The production of sex hormones can result solely from genetics or from genetics in combination with the influence of environmental factors. Pough, F. Estrogen and sex reversal in turtles: a dose-dependent phenomenon. McGowanR. Keywords: Sex determinationReptilesTurtlesHormones.
Abstract Most hypotheses that have been put forward in order to explain the persistence of environmental sex determination ESD in reptiles assume a relatively fixed association of sex with temperature-induced phenotype and no maternal influence on offspring sex.
Nature— New Jersey: Prentice Hall, DiNapoli L, Capel B Germ cell depletion does not alter the morphogenesis of the fetal testis or ovary in the red-eared slider turtle Trachemys scripta. Sinauer Associates, Sunderland Google Scholar. Carson R Silent Spring. Ferguson MJ The reproductive biology and embryology of crocodilians.
In some species, including most mammals and insects, sex is determined solely by chromosomes; in other species, sex is a matter of environmental conditions. Dynamics of littoral fishes and decapods along a coastal river-estuarine gradient. We predicted that male desert gobies would adjust their courtship to their social and physical environment.
A general association between the size of an animal and its sex is proposed for several types of vertebrate. Temperature-dependent sex determination in reptiles Location-dependent sex determination in Bonellia and Crepidula.