Most of us are familiar with the neighborhood squirrels that flit from tree to tree, scamper along the top of fences or quarrel with bluejays over peanuts left out in the back yard. The squirrels of North America are a diverse group of mammals, however, that range from ground-dwelling squirrels living in tremendous underground colonies to flying squirrels that sail from tree to tree silently in the night. Whether you are deep in the wilderness of...