Movement is usually driven by high population density and competition for territory. But today numbers are actually falling due to climate-caused impacts, Dalén noted.
"In a decreasing population, which was likely the case when the Ice Age was gone, probably there were lots of empty territories," he said.
So instead of moving to more northerly latitudes, the arctic foxes gained altitude, Dalén suggested, taking to higher areas such as the Alps.
But the killer blow may have been the arrival of red foxes as milder conditions took hold.
"Red foxes, which are twice the size, could suddenly survive in these areas and out-compete the arctic foxes," Dalén said. "The red foxes probably came in and took over the lowland areas, and the arctic foxes got marooned."
History may already be repeating itself. The recent northward spread of red foxes into polar regions in Europe and North America is being linked to the disappearance of the Arctic species in some regions.
Conservationists say Scandinavia's arctic fox population, with fewer than 200 individuals remaining, now faces serious threat of extinction. Culling of red foxes has been introduced in arctic fox territories.
The study team says its findings have far-reaching implications for understanding how species respond and adapt to climate change, suggesting that many animals could be more vulnerable to global warming than previously thought.
"Arctic species may be unable to track the shifting habitat as the temperature increases," the researchers write. "This may result in losses of genetic variation as local populations become extinct."
Dalén said similar studies are needed, because the ability of a species to follow climate-caused shifts in habitat isn't properly considered when predicting how the creature might respond to future warming.
"Personally, I suspect most Arctic species will behave like the arctic fox," he said. "I would be very surprised, for example, if polar bears behaved differently."
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