Warming World Shrinks Salamanders
In ancient mythology, salamanders could withstand fire. In modern times, though, just a small warming has been enough to dramatically change them—and perhaps threaten their future. Salamanders in the southern Appalachian Mountains of Tennessee, North Carolina, and Virginia have gotten smaller over the past 50 years due to increasing temperatures in their habitats, a new study has concluded. It’s the first confirmation that climate change can alter body size, a connection that had only been hypothesized in the past, and one of the fastest studied responses to changing temperatures on record.
“This is helping us understand yet another way in which climate change could play out,” says ecologist Michael Adams of the U.S. Geological Survey in Corvallis, Oregon, who was not involved in the new work. “In this case, we’re learning how it can change the life history of an organism.”
Over the past decade, scientists have documented several population declines in amphibians, including salamanders. But the causes of these declines have been hard to work out; some are due to disease, others to habitat loss or invasive species. Karen Lips, a biologist at the University of Maryland, College Park, wanted to determine what was behind dropping numbers of Plethodontidae, or lungless salamanders, across the eastern United States. The Appalachians are home to more salamander species than any place on Earth, many unique to the area. The Plethodontidae, the most numerous, represent a large and diverse family of salamanders that all respire through their skin. The salamanders play a key role in the ecosystems of the mountains, consuming insects that are too tiny for most other vertebrates.
| image by Michael Redmer