Biology
Adaptive Significance of Seasonal Molting and Camouflage in Arctic Foxes
Quick fact
Arctic foxes shed their brown summer coat and grow a pure white one each autumn, triggered by shortening day length rather than temperature. This allows them to remain camouflaged against snow, but as winters become shorter with climate change, foxes can be left startlingly white against bare ground.
Why this is interesting
In the Arctic, a fox's wardrobe is a matter of life and death. How does a single animal change its coat from brown to white and back again, and what happens when the snow doesn't come?