Feathers and Function: camouflage

Some birds have camouflaged plumage which serves as an adaptation to the surroundings.
The ptarmigan is a master of camouflage – its plumage has a different colour to fit the season: in winter snow-white and in summer speckled black and brown.
Due to its change of plumage this inhabitant of barren mountain environments is hidden from the eyes of its predators all year round.