Melanism

Melanism is a phenomenon which occurs when a living organism has an unusually high amount of melanin in its skin, fur, or feathers. Melanism is associated with adaptation to darker environments, and is known to be seen in many species, including some species of mammals, reptiles, birds, and even fish. In mammals, melanism has been linked to increased fitness, as well as to the ability to more effectively camouflage in certain habitats. It has been linked to survival in certain harsh, environmentally challenging conditions and can be a major factor in predator-prey interactions. Melanism is often seen as an evolutionary advantage, but can also result in reduced reproductive success and decreased fitness in other contexts.