Climate Change and Interbreeding: New Finding

Will we have squirrel-chipmunks, and crow-bluejays? It sounds appalling, but researchers at the University of Washington's Climate Impacts Group think that, in most cases, the chances of interbreeding as animals narrow their ranges in climate change won't be quite that serious. Those scientists said in their recent report in Nature Climate Change that although changing temperatures are shifting species' ranges and bringing many closely related species into contact, only 6 percent of closely related species across North and South America whose ranges don't already overlap are likely to cross paths by the end of this century.

In other words, not as many animals might interbreed as a result of criss-crossing ranges, as has been suggested in the past-such as by a 2010 editorial in the journal Nature, which said interbreeding might lead to "an Arctic melting pot."

"People have been concerned that climate change would be bringing all these species into contact, and that this could unleash a wave of interbreeding," co-author Meade Krosby at UW said in a release. "What we found is, not so much."

Land managers have also been concerned, telling Krosby that they work with closely related species separated by small distances, according to Eurekalert.

The study looked at 9,577 pairs of closely related species of birds, mammals and amphibians in North and South America. For the 4,796 pairs whose ranges presently do not overlap, computer models show that about 6.4 percent of them will have contact because of climate change by the year 2100, Eurekalert said.

The tropics, and birds there, saw the highest overlap among species, probably because more species live in the tropics and birds cover wide distances, Krosby said in the release.

It's still important for wildlife biologists to consider their region and animals of interest, to best protect specific populations - but the big picture will likely not be a huge problem, says Krosby in a release.

We can increase biodiversity by linking habitats that have been fragmented by human activity, however--so that species can move and shift to stay comfortable in climate change, Krosby notes in a release.

 "If people are worried that wildlife corridors and other ways to increase connectivity could bring these species into contact, we're saying: That's probably not going to happen, and allowing species to move is far more important," says Krosby in a release.

Co-authors are currently at the University of Washington; California State University Monterey Bay; and the Georgia Institute of Technology, said the release.

Follow Catherine at @TreesWhales