UA study: Species can't evolve fast enough to adjust to climate change
As temperatures around the world rise, a recent study has shown hundreds of species would need to evolve about 10,000 times faster than they have in the past to adapt to the rapid climate change expected in the next 100 years.
The study, which was led by University of Arizona ecologist John J. Wiens, analyzed the way species adapted to climate change in the past, using data from 540 living species from all major groups of terrestrial vertebrates, including amphibians, reptiles, birds and mammals, UA spokesman Daniel Stolte said in a news release.
Weins and Ignacio Quintero, a postgraduate research assistant at Yale University, then took projections for climate change through the year 2100 and compared them to years past.
"We found that on average, species usually adapt to different climatic conditions at a rate of only by about one degree Celsius per million years," Wiens said in the release. "But if global temperatures are going to rise by about four 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."
The rapid change in climate could lead to species from each of the primary terrestrial vertebrate groups to become endangered, if not extinct altogether, the study said.
As temperatures continue to rise, species will begin relocating to different climates. Some species will not be able to physically make the move to higher elevations or latitudes without risking potential extinction, Wiens said.
"With the tropical species, the problem seems to be that there are narrower niches, especially with temperature," Wiens said in a phone interview. "So the problem for them is that because their niches are narrow, there's very little overlap between the present and future climates."
As species begin to relocate, identifying areas that have not been domesticated by people could also become an issue.
"There's other ways species could adjust to climate change. They might move upwards in elevation, or they could acclimate," Wiens added. "One example of acclimation is they could spend more time in the shade. It's not really evolutionary, but it is a response to climate change. They can't do those things if they can't move and therefore can't acclimate."