Black wolves should probably not exist. The same species as
their gray relatives, these wolves have a genetic mutation that
causes them to produces excess melanin, a pigment responsible
for coat color. The origin of black wolves has long been a
puzzle. Unlike domestic animals, wild species usually don’t
exhibit such dramatic variations in coloration, especially
within the same population. While all tigers are orange and
striped, and all grizzly bears are brown, “gray” wolves range
from pure white to brown to red to black. Researchers at
Stanford University have discovered that dogs may be the cause
of the wolves’ unusual coloration. Dogs have a unique gene for
melanism, which is also shared by European, Asian and American
black wolves. Scientists estimate that the gene arose somewhere
between 12,779 and 121,182 years ago, with a preferred time of
around 50,000 years. Even if European wolves were the first to
don a black coat, it was domestic dogs that brought the gene to
the wolves (and coyotes) of North Amer