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In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

What is the trick of countershading?, Context: Domestic dogs often display the remnants of countershading, a common natural camouflage pattern. A countershaded animal will have dark coloring on its upper surfaces and light coloring below, which reduces its general visibility. Thus, many breeds will have an occasional "blaze", stripe, or "star" of white fur on their chest or underside.
Output:
coloring