Tracing the fox family tree: the North American red fox has a diverse ancestry forged during successive ice ages

Abstract

The red fox is one of the most widespread and adaptable mammals on Earth. In the American West, however, there are populations of native red foxes that occur only in alpine and subalpine habitats, which may be at risk from human-caused and natural pressures. One potential threat is global climate change, which is likely to reduce both the amount and connectivity of suitable habitat for these unique red foxes. Until recently, the evolutionary history of native North American red foxes, which also occur in the boreal forests of Canada and Alaska, was largely speculative.

As a doctoral student in the early 1980s, Keith Aubry, now a research wildlife biologist with the Pacific Northwest Research Station, conducted an intensive study of North American red foxes, especially the montane populations. Based on fossil, archeological, historical, and ecological evidence, he hypothesized that, contrary to prevailing theory, native red foxes arose from two distinct lineages that had been isolated from each other during the last glaciation. Using modern molecular genetics, a team of researchers led by Aubry has confirmed his hypothesis and revealed important new details about the evolutionary history of North American red foxes. Their analyses provide the foundation for revealing the red fox's genealogy at finer levels, and aid conservation efforts by making it possible to distinguish native from non-native populations and identify those that may be threatened.

Citation

Wells, Gail. 2011. Tracing the fox family tree: the North American red fox has a diverse ancestry forged during successive ice ages. Science Findings 132. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 5 p.