Eryst

Eryst, also known as Erythristic, refers to a rare genetic mutation that causes an animal to have an overabundance of red pigment in its fur or feathers, often resulting in a reddish or orange coloration where the animal would typically be black, brown, or grey. This condition is distinct from albinism, which involves a complete lack of pigment, and melanism, which is an excess of dark pigment. Erythristic animals are often referred to as "red" variants of their species.

The genetic basis for erythrism varies depending on the species. It can be caused by a mutation in genes responsible for melanin production or distribution. In some cases, the mutation affects the production of pheomelanin, the reddish-yellow pigment, leading to its increased expression. In other instances, it may involve a reduction in eumelanin, the black-brown pigment, allowing the underlying red tones to become more prominent.

Erythrism can occur in a wide range of animals, including mammals, birds, reptiles, and amphibians. For example, erythristic foxes, squirrels, and deer have been documented. In some species, the erythristic trait may be more common than in others, but it is generally considered a rare occurrence. The survival rate of erythristic animals in the wild can be affected by their unusual coloration, potentially making them more conspicuous to predators or less effective at camouflage. However, in some environments, the reddish hue might offer a degree of camouflage.