In what condition is crocodile sex formed?

The sex of developing crocodilians is determined by the incubation temperature of the eggs. This means crocodilians do not have genetic sex determination, but instead have a form of environmental sex determination which is based upon the temperature embryos are subjected to early in their development.

Crocodile embryos do not have sex chromosomes, and unlike humans sex is not determined genetically. Sex is determined by temperature, with males produced at around 31.6 °C, and females produced at slightly lower and higher temperatures. The average incubation period is around 80 days, and also is dependent upon temperature.