Genetic study clarifies evolutionary origin of elusive montane red fox

May 20, 2011

North American red foxes originated from two separate genetic lineages that were isolated from each other by glaciers some half a million years ago, according to a U.S. Forest Service Pacific Northwest Research Station study.

The research—featured in the April/May 2011 issue of Science Findings, a monthly publication of the station—can assist efforts aimed at conserving potentially imperiled montane populations of the species.

"When most people think of the red fox, they envision the ones that thrive in low-elevation, human-dominated landscapes," said Keith Aubry, a research wildlife biologist at the station who led the study. "But there are other extremely elusive and rarely seen populations that live only in isolated alpine and subalpine areas in the mountains of the Western United States."

The latter group—the montane —may be imperiled by climate change and other contemporary pressures and were the focus of Aubry's doctoral work in the early 1980s. Contrary to prevailing theory at the time, Aubry hypothesized that native North American red foxes were descended from two distinct lineages, not one, that were isolated from each other in both northern and southern ice-free areas during the most recent Ice Age. Such an evolutionary history would help explain the unique ecological adaptations of the montane foxes, and why native red foxes in southern British Columbia are so much bigger than the montane foxes that occupy nearly adjacent areas in Washington's Cascade Range.

"If all of North America's foxes originated from a single lineage that had expanded its distribution in a wave across the continent, you'd expect to see a more or less continuous gradient in size," Aubry said. "But there was an abrupt discontinuity in size in that area, suggesting that the montane red foxes had evolved in isolation from the northern populations," Aubry said.

Only recently were Aubry and his colleagues able to test this hypothesis through genetic analyses of 285 museum specimens and a close examination of fossil, archeological, historical, and ecological records. They found that North American red foxes did, indeed, stem from two distinct lineages that diverged from each other while they were isolated in both the southern and northern parts of the continent during the last Ice Age. Moreover, Aubry suspects that montane foxes' smaller size and high-elevation habitat preference is indicative of their being descendants of ancient foxes that had inhabited the southern part of the continent.

With knowledge of the evolutionary history and genetics of the North American red fox, managers can distinguish native from nonnative populations and can clarify genetic relationships among subspecies—knowledge that, in turn, can be used to target conservation efforts to the appropriate gene pool.

Explore further: Study: Foxes can't outfox coyotes

More information: To read the April/May 2011 issue of Science Findings online, visit www.treesearch.fs.fed.us/pubs/37702

Related Stories

Study: Foxes can't outfox coyotes

May 25, 2006

Illinois wildlife biologists say coyotes, known to be killers of domestic pets, might also be causing a decline in the Chicago area's fox population.

Tasmania plans to eradicate red foxes

November 20, 2006

Tasmania plans to spend millions of dollars destroying red foxes, an animal that until recently was thought not to have spread there.

Foxes get frisky in the far north

July 17, 2007

Bees do it, chimps do it… Now it seems Arctic foxes do it, too. New research looking at the DNA fingerprints of canids in the Far North has revealed that foxes once thought to be monogamous are in fact quite frisky.

Fox spit helped Forest Service confirm rare find

September 3, 2010

(PhysOrg.com) -- Three weeks ago, when U.S. Forest Service biologists thought they had found a supposedly extinct fox in the mountains of central California, they turned to UC Davis for confirmation.

Recommended for you

Genomes uncover life's early history

August 24, 2015

A University of Manchester scientist is part of a team which has carried out one of the biggest ever analyses of genomes on life of all forms.

Rare nautilus sighted for the first time in three decades

August 25, 2015

In early August, biologist Peter Ward returned from the South Pacific with news that he encountered an old friend, one he hadn't seen in over three decades. The University of Washington professor had seen what he considers ...

Why a mutant rice called Big Grain1 yields such big grains

August 24, 2015

(Phys.org)—Rice is one of the most important staple crops grown by humans—very possibly the most important in history. With 4.3 billion inhabitants, Asia is home to 60 percent of the world's population, so it's unsurprising ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.