Planet's Amphibians "Just Can't Keep Up" With Multiple Threats - 1/3 Facing Extinction [View All]

[hatrack]

Despite surviving the age of dinosaurs and numerous bouts of severe climate change, amphibians are not keeping pace with the current rate of global change, reports a new study published in the journal Bioscience.

"We know that there are various causes for amphibian population declines, including UV-B light exposure, habitat loss, pesticide pollution, infections and other issues," said Andrew Blaustein, author of the study and a professor of zoology at Oregon State University. "But looked at in a different way, it's not just that there are threats and pressures amphibians have to deal with. There have always been threats, and these have been some of the most adaptive and successful vertebrate animals on Earth. They were around before the dinosaurs, have lived in periods with very different climates, and continued to thrive while many other species went extinct. But right now, they just can't keep up."

More than a third of the world's 5,743 known species of amphibians are threatened, while 168 species are believed to have gone extinct in recent years. Blaustein says that amphibians are especially at risk "because their physiology and complex life cycle often exposes them to a wider range of environmental changes than other species must face – they have permeable skin, live on both land and water, their eggs have no shells."

"Historically, amphibians were adept at evolving to deal with new conditions," Blaustein said. "What they are doing is showing us just how rapid and unprecedented are the environmental changes under way. Many other species will also be unable to evolve fast enough to deal with these changes. Because of their unique characteristics, the amphibians are just the first to go."

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