Could Climate Change be Causing Salamanders to Shrink?

Climate change may be causing salamanders to shrink. According to researchers at Clemson University, they found that warming environments could be the reason.

For the study, researchers examined salamanders caught in the Appalachian Mountains between 1957 and 2007 as well as 2011 and 2012. Researchers discovered that salamanders caught from 1980 onward were eight percent smaller than those seen in earlier years, with changes most prevalent in parts of the Southern Appalachians where the climate is significantly hot and dry.

"One of the stresses warmer climates will impose on many organisms is warmer body temperatures," said Michael W. Sears of the biological sciences department, in a news release. "These warmer body temperatures cause animals to burn more energy while performing their normal activities. All else being equal, this means that there is less energy for growth."

Researchers used a computer program to examine the effects of climate change on animals. They created an artificial salamander that allowed them to estimate how many calories the creature could burn. By simulating minute-by-minute behavior, different simulations showed that these creatures were typically just as active as their ancestors despite their the creature's difference in size.

"Ectothermic organisms, such as salamanders, cannot produce their own body heat," Sears added. "Their metabolism speeds up as temperatures rise, causing a salamander to burn seven to eight percent more energy in order to maintain the same activity as their forebears."

As the salamander's change in body size is one of the fastest ever recorded, researchers believe that this may show just how this and other animals might adjust to different environmental conditions over time.

"We do not know if decreased body size is a genetic change or a sign that the animals are flexible enough to adjust to new conditions. If these animals are adjusting, it gives us hope that some species are going to be able to keep up with climate change," concluded Karen R. Lips, the paper's co-author, and an associate professor at the University of Maryland's (UMD) department of biology.

More information regarding the findings can be seen via the journal Global Change Biology.