Climate warming changing male lizards into females, Australia

Just though some of you might want to know about this.

Science Daily/University of Canberra, Au./Claudia Doman, 7/4/15.  "Climate change is turning male dragon lizards into females." 

All I said was,"welcome warm weather"

"A climate-induced change of male dragons into females occurring in the wild has been confirmed for the first time, according to University of Canberra research recently published on the cover of international journal Nature. 

And now, when I grow up I'll be a girl

  The researchers, who have long studied Australia's bearded dragon lizards, have been able to show that a reptile's sex determination process can switch rapidly from one determined by chromosomes to one determined by temperature.

Lead author Dr Clare Holleley, a postdoctoral research fellow at the University of Canberra's Institute for Applied Ecology, explained: "We had previously been able to demonstrate in the lab that when exposed to extreme temperatures, genetically male dragons turned into females."

"Now we have shown that these sex reversed individuals are fertile and that this is a natural occurring phenomenon." "We also found that sex-reversed mothers -- females who are genetic males -- laid more eggs than normal mothers," Dr Holleley said. "So in a way, one could actually argue that dad lizards make better mums."

University of Canberra Distinguished Professor Arthur Georges, senior author of the paper, also highlighted the importance that these discoveries have in the broader context of sex determination evolution."The mechanisms that determine sex have a profound impact on the evolution and persistence of all sexually reproducing species," Professor Georges said. "The more we learn about them, the better-equipped we'll be to predict evolutionary responses to climate change and the impact this can have on biodiversity globally."  Read more. 

Reference, article. Nature International weekly journal of science/v523/n7558/pp 5-122, about the cover. "An Australian bearded dragon (Pogona vitticeps) seen basking near the township of Eulo in the semi-arid zone of western Queensland. ....Various mechanisms have been proposed to explain the transition, including a role for sex reversal. Clare Holleley et al. present the first report of reptile sex reversal in the wild, associated with rapid transition between genetic and environmental sex determination. They observe sex reversal in P. vitticeps at the warmer end of its geographic range. When sex-reversed females mate with normal males, the chromosomal sex determination system is lost and temperature-dependent sex determination is established. It is not known whether climate-induced changes in sex determination are advantageous or detrimental to the process of evolutionary adaptation."

Photographs/graphics.  Bearded dragon lizard face view from The Pet Directory. The measured bearded dragon lizard juvenile is estimated to be about 3 months old  (average length is 8-11 inches); whereas, a 12 month old adult lizard is about 16-22 inches in length-- information from The Bearded Dragon.

Posted by Kathy Meeh