Sheep are white so that they blend in with a natural limestone scenery (eg the Yorkshire Dales). A white (or grey) sheep blends in perfectly with a rocky background, whilst it looks more like a small rocky outcrop when against a green background. Often a walker not used to the higher altitudes and camouflaged sheep will stand on a 'rock' and find it moving quickly from underneath him. The walker usually ends up feeling rather sheepish after such an encounter.
Richard Marsden Leeds
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