The Bearded Dragon Mystery

I recently learned an interesting scientific fact about bearded dragons. The gender of bearded dragons are dependent on both, genetics and temperature, which is very unusual. Even individuals with male chromosomes (ZZ) can develop as females if their eggs are incubated at high temperatures. Which is a mystery that has puzzled scientists for decades.

Two independent research teams recently solved this by producing near-complete genomes of the central bearded dragon. Both studies identified Amh (anti-Müllerian hormone) as the most likely master sex-determining gene. The gene sits on the Z chromosome and shows strong male-biased expression, meaning males have a double dose compared to females.

This discovery marks the first clear identification of a master sex gene in a reptile and provides new insight into how environmental factors like temperature can override genetic instructions.

https://senecaparkzoo.org/bearded-dragon/

This finding is especially relevant as global temperatures continue to rise. Because high incubation temperatures can override genetic sex signals in bearded dragons, warming climates could skew gender ratios toward females in wild populations. Over time, this imbalance may reduce breeding success and threaten population stability. This new research helps scientists identify which species are at risk, and gives them the opportunity to develop remedies.

Reference: SciTechDaily. Bearded Dragons Can Switch Sex. Scientists Finally Found Out How. August 26, 2025. https://scitechdaily.com/bearded-dragons-can-switch-sex-scientists-finally-found-out-how/