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Coyotes-Wolves-Cougars.blogspot.com

Grizzly bears, black bears, wolves, coyotes, cougars/ mountain lions,bobcats, wolverines, lynx, foxes, fishers and martens are the suite of carnivores that originally inhabited North America after the Pleistocene extinctions. This site invites research, commentary, point/counterpoint on that suite of native animals (predator and prey) that inhabited The Americas circa 1500-at the initial point of European exploration and subsequent colonization. Landscape ecology, journal accounts of explorers and frontiersmen, genetic evaluations of museum animals, peer reviewed 20th and 21st century research on various aspects of our "Wild America" as well as subjective commentary from expert and layman alike. All of the above being revealed and discussed with the underlying goal of one day seeing our Continent rewilded.....Where big enough swaths of open space exist with connective corridors to other large forest, meadow, mountain, valley, prairie, desert and chaparral wildlands.....Thereby enabling all of our historic fauna, including man, to live in a sustainable and healthy environment. - Blogger Rick

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Friday, May 20, 2011

In biogeography, Montane refers to highlands located below the subalpine zone............. Montane regions generally have cooler temperatures and often have higher rainfall than the adjacent lowland regions, and are frequently home to distinct communities of animal and plant species.....Wildlife biologist Keith Aubry out of the USFS Pacific Northwest Station has concluded that there are two historical lineages of North American Red Foxes.............one that originated North of the most recent Ice Age and another that originated to the South of that Ice Age,,,,,,,,,,The Montane foxes are smaller in size from their flatland bretheren and appear to be descended from those foxes that lived South of the Ice sheets

Genetic study clarifies evolutionary origin of elusive montane red fox

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 red foxes—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.

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