A black wolf is a melanistic colour variant of the gray wolf (Canis lupus). Black specimens are recorded among red wolves (Canis rufus), and these colour variants are probably still around today. Genetic research from the Stanford University School of Medicine and the University of California, Los Angeles revealed that wolves with black pelts owe their distinctive coloration to a mutation which occurred in domestic dogs, and was carried to wolves through wolf-dog hybridization. Besides coat and knee colour , they are normal grey wolves.
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