The Evolution of the Black Squirrel
The black squirrel is basically the product of interbreeding among the squirrel species. The cause of the black fur is Melanism, a mutation in the pigment gene passed on by fox squirrels to grey squirrels. Squirrels with one copy of this gene have brownish-black fur while those with two copies have fully black fur. Scientists discovered that England’s black-furred grey squirrels have a gene that mirrors a gene found in black fox squirrels, which are native to the North American continent. Additionally, they observed that the gene is flawed in that it is missing an element that is found in the gene carried by the fox squirrel. This combined with evidence pointing to the two squirrel species being very closely related, convinced scientists that there was a definite connection. They came to the conclusion that mating between the two squirrel species resulted in the transfer of the gene from fox to grey squirrels. This idea of mating between squirrel species came about as scientists observed squirrels doing their ‘mating chases’ during which male squirrels chase the female squirrels they have marked for mating. Observers noticed that mating chases took place between different species of squirrels, indicating that squirrels do not stick to their own subspecies when mating.Is There Something Super About the Black Squirrel?
This unique fur colour may be a good thing for squirrels as it makes them special. Scientists believe that this gene may give black squirrels greater ‘cold’ endurance, thereby increasing their ability to endure harsh winters better than other squirrel species. This explains, in part, why these squirrels have been able to migrate further north into the colder temperatures of places like Canada than other squirrels.Black Squirrels in the Home
