The Bearded Dragon Lizards living in Australia sure are a weird and fascinating bunch. It turns out that global warming is too much for the male members of the species, so, in response, they’re doing the only logical thing that they can – they’re literally changing their sex and becoming female lizards.
Dr Clare Holleley, lead author associated with the University of Canberra, gave a statement saying that “This is the first time we have proved that sex reversal happens in the wild in any reptile at all”.
She went on to add that the study shows that temperatures affect how a species evolves. If members of a species are going to have to face significantly higher temperatures than what they’re used to, than that is going to affect their biology.
Researchers from the University of Canberra published the study earlier this week, on Wednesday (July 1, 2015), in the journal Nature, and revealed that the rising temperature of the planet is causing male reptiles to change into females at such a rapid rate that the world could soon end up having female-only populations for certain species.
One of the main questions that the team tried to answer with their projects was whether or not the Bearded Dragon Lizards would develop a way to adapt to the heat. If they hadn’t, the species would have most likely entered the early stage of their extinction.
Before global warming started messing with their biology, the animals were either born with a W chromosome, or they weren’t. If an animal had both a W chromosome and a Z chromosome, that would make them a female. If they only had a Z chromosome, that would make them a male member of the species.
Past studies have shown that if lizards are exposed to extreme heat inside the lab, they will their sex. What’s special about this study is that it’s the first one to ever detect such a behavior into the wild.
In order to prove their findings, Dr Holleley and her team caught and examined 131 Bearded Dragon Lizards living in the wild. They soon noticed that 11 of them looked like females on the outside, and even had younglings, but that on the genetic front they had the ZZ chromosome associated with male members of the species.
Professor Arthur Georges, co-author and chief scientist over at the University of Canberra’s Institute for Applied Ecology, gave a statement of his own, sharing that, curiously enough, the ZZ chromosome females laid more eggs, which for some reason means that they would make better mothers.
What’s more interesting is that the offspring belonging to these new females are no longer determined by chromosomes, but by incubating temperature, a process found in related species such as alligators.
The researchers themselves admitted that 11 is a small number, however it still proves that the phenomenon is happening, and Dr Holleley has said that she has every intention to conduct further research in the matter.
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