Global warming could kill off as many as a fifth of the world's lizards by 2080, with potentially devastating consequences for ecosystems around the world, according to a new study.
Researchers who conducted a major survey of lizard populations worldwide, which appears today in the journal Science, say lizards appear to be especially sensitive to the effects of climate change and are dying off at an alarming rate.
The loss of the lizard populations could wreak havoc with ecosystems in which they are a crucial part of the food chain, since they are important prey for many birds, snakes, and voracious predators of insects.
The biologists in the study ruled out factors other than global warming as being responsible for the rapid decrease in the lizard population.
"We did a lot of work on the ground to validate the model and show that the extinctions are the result of climate change," says Dr Barry Sinervo, professor of ecology and evolutionary biology at the University of California at Santa Cruz.
"None of these are due to habitat loss. These sites are not disturbed in any way, and most of them are in national parks or other protected areas," he says.
The scientists worked up models based on predicted probabilities of local extinction showing the likelihood of species extinction was estimated to be 6% by 2050 and 20% by 2080.
Earlier models, they say, have accurately predicted the extinctions of lizard population on five continents around the world.
Too much of a good thing
The researchers say they first noted the disappearance of lizard populations in France and later in Mexico, where 12% of lizard populations are thought to have died out.
Although generally thought to be sun-loving creatures, higher temperatures have proved to be too much for many lizard species, causing them to restrict their activity, including limiting their efforts to find food.
Villanova University's Professor Aaron Bauer, who specialises in African lizards, says scientists are engaged in a race against time to find and document research on the endangered reptiles.
"In many parts of the world, lizards are almost certainly going extinct due to climate change before their very existence is known to biologists," he says.