A howling wolf from Alaska.
As black colored wolves occur more frequently in forested areas than on the tundra (black coats occur in about 62% of wolves in the forested areas of the Canadian Arctic, compared with about 7% in the icy tundra, melanism was concluded by the researchers to give those wolves an adaptive advantage.
The mutation’s purpose has not yet been identified. Dr Barsh ruled out camouflage, as wolves have few natural predators, and there is no evidence that a black coat color leads to any increase in hunting success rates.
Dr. Barsh observed that beta-defensin is involved in providing immunity to viral and bacterial skin infections, which might be more common in forested, warmer environments.
It has been suggested that the mutation's association with forested habitats means that the prevalence of melanism should increase as forests expand northward. Dark fur is believed to be dominant in wolves.
A mating between a black and a gray wolf resulted in ten pups with dark fur out of a total of fourteen.