Climate change could present species with choice: evolve or die

TUCSON, July 10 (UPI) -- Many species would have to speed up their evolution by 10,000 times to adapt to the rapid climate change expected in the next 100 years, a U.S. ecologist says.

A study led by University of Arizona researcher John J. Wiens analyzed how quickly species adapted to different climates in the past, then compared their rates of evolution to rates of climate change projected for the end of this century.

The results, published in the journal Ecology Letters, suggest many terrestrial vertebrate species appear to evolve too slowly to be able to adapt to the dramatically warmer climate expected by 2100 and could face extinction if they are unable to move or acclimate.

"Every species has a climatic niche which is the set of temperature and precipitation conditions in the area where it lives and where it can survive," Wiens, a professor of ecology and evolutionary biology, said. "For example, some species are found only in tropical areas, some only in cooler temperate areas, some live high in the mountains, and some live in the deserts.

"We found that on average, species usually adapt to different climatic conditions at a rate of only by about 1 degree Celsius per million years," Wiens said. "But if global temperatures are going to rise by about 4 degrees over the next hundred years as predicted by the Intergovernmental Panel of Climate Change, that is where you get a huge difference in rates.

"What that suggests overall is that simply evolving to match these conditions may not be an option for many species."