Bearded dragon lizards capable of gender change

Bearded dragon lizards are capable of easily changing their gender in the egg itself, new research says.

Researchers from the University of Canberra found this phenomenon -- called sex reversal -- where an animal's chromosomes and what they look and act like physically do not match up.

"This is the first time ... in a reptile, that we've actually found and established that sex reversal happens in the wild," said Claire Hollely, from the University of Canberra.

Researchers studied 131 adult lizards, using controlled breeding experiments.

"They reproduce, and are completely functional females," Hollely said.

If the species is a he-she animal -- with male sex chromosomes, but reproducing as a female -- it laid almost twice as many eggs as a regular female.

In other words, fathers make better mothers. The cause for the sex reversal is to be explained in terms of climate change.

"If you get exposed to a hot temperature during that period of sensitivity, that's what causes sex reversal in these animals," Hollely said.

Hollely said the most interesting and unexpected finding from this work was that sex-reversed females appeared to be more fit than regular females, ABC.net.au reported.

"If you're a he-she animal -- with male sex chromosomes, but reproducing as a female -- you actually laid almost twice as many eggs as a regular female," Hollely said.

"Whether or not this is due to an increase in global temperatures is something we have to pin down in future research," Hollely added.

The study appeared in the journal Nature.