Temperature-Dependent Sex Determination in Crocodilians and Climate Challenges

• Published in: Animals (Basel) Vol. 14; no. 13; p. 2015
• Main Authors: Schilling-Tóth, Boglárka Mária, Belcher, Scott M, Knotz, Josefine, Ondrašovičová, Silvia, Bartha, Tibor, Tóth, István, Zsarnovszky, Attila, Kiss, Dávid Sándor
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 08.07.2024
• Subjects: Alligators; anti-Müllerian hormone; aromatase; crocodile sex determination; Crocodiles; Embryos; Females; Males; Ovaries; Ratios; Reptiles & amphibians; Sex chromosomes; SF-1; SOX-9; Temperature effects; TRPV; SF-1; TRPV; aromatase; DNA methylation; crocodile sex determination; miRNA; anti-Müllerian hormone; SOX-9; climate change
• ISSN: 2076-2615; 2076-2615
• DOI: 10.3390/ani14132015

The sex of crocodilians is determined by the temperature to which the eggs, and hence the developing embryo are exposed during critical periods of development. Temperature-dependent sex determination is a process that occurs in all crocodilians and numerous other reptile taxa. The study of artificial incubation temperatures in different species of crocodiles and alligators has determined the specific temperature ranges that result in altered sex ratios. It has also revealed the precise temperature thresholds at which an equal number of males and females are generated, as well as the specific developmental period during which the sex of the hatchlings may be shifted. This review will examine the molecular basis of the sex-determination mechanism in crocodilians elucidated during recent decades. It will focus on the many patterns and theories associated with this process. Additionally, we will examine the consequences that arise after hatching due to changes in incubation temperatures, as well as the potential benefits and dangers of a changing climate for crocodilians who display sex determination based on temperature.