Black cats have been associated with bad luck in some Western cultures. There isn't one specific reason for this belief, but it seems to be a combination of folklore and superstition beginning in the Middle Ages.
Black cats are actually lucky. The gene that gives black cats a dark coat makes them less susceptible to disease than light-colored cats. Melanism is when an organism has a more than usual dark pigment. It comes from the word "melanin," the pigment that gives color to skin, hair and eyes. Melanism is the opposite of albinism (when skin has lack of pigment) and it is the reason for a cat's complete black fur. Scientists believe that this genetic quality keeps black cats healthier by making their cells more resistant to infections.
Melanism also makes animals better hunters since they are practically invisible at night. So contrary to what some people may say or believe, black cats are indeed lucky.
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