I was up in Bronxville, New York this past weekend at a house party and saw a few black squirrels running around in the back yard. It reminded me of the ones that I used to get at my house in Michigan, including this guy here peeking out of a hole in a tree. Black squirrels are actually a melanistic subgroup of the eastern grey squirrel that carry a mutant black pigment gene. They are common in the Midwestern United States, Ontario, Quebec and parts of the Northeastern United States and Britain.  One theory suggests that they have thrived in these colder areas because their dark fur gives them the advantage of heat retention over grey colored squirrels.