Mr. WildsideMr. Wildside fun fact
Arctic foxes have some of the warmest fur of any mammal
In a review of how arctic foxes survive the polar winter, biologist Pål Prestrud described their winter fur as the best-insulating of all mammals.
The coat changes with the seasons. It's thick and white in winter to match the snow, then turns a thinner grey-brown in summer to blend in with the rocky tundra.
Even the hairs change. A study of Arctic mammals found that white winter hairs have larger cores packed with air-filled cells, which may help hold in heat.
Wear the Arctic Fox
A white arctic fox in a moonlit snowfield under shimmering northern lights.