May 9 (UPI) -- As the planet heats up, microbes inside the guts of lizards are being killed off.
In a series of lab tests, researchers at the universities of Exeter and Toulouse found rising temperatures alter the microbiota of common lizards, or viviparous lizards. The findings -- detailed in the journal Nature Ecology and Evolution -- offer further proof that almost nothing remains untouched by the effects of global warming.
Researchers placed several dozen common lizards, Zootoca vivipara, inside temperature-controlled confines. Scientists then sequenced each lizard's gut microbiota before turning up the temperature in the cages of the half of the lizards.
Warming of 2 to 3 degrees Celsius precipitated a decline in microbial diversity inside the lizard's guts. A reduction in microbiota diversity was associated with a decline in survivability.
"Our research shows that a relatively small rise in temperature can have a major impact on the gut bacteria in common lizards," said Elvire Bestion, a researcher at Exeter's Environment and Sustainability Institute, said in a news release.
Researchers plan to conduct similar experiments using other ectotherms, including reptile and amphibian species. Ectotherms are cold-blooded and rely on external sources to regulate body temperature.
Global warming remains the gravest threat faced by plants and animals, Bestion argues, but few studies have looked as the affects of temperature change on microbes vital to plant and animal health.
"We are only now starting to understand the importance of gut microbiota in the physiology of all species, including humans," she said. "These bacteria are linked to everything from digestion to immunity and obesity."