14, 000 and 150, 000 years. In this time, the dog has developed into hundreds of breeds with a degree of variation. For example, heights ranging from just a few inches (such as the Chihuahua) to nearly three feet (such as the Irish Wolfhound), and colors ranging from white to black with red, grays, and browns also occurring in a tremendous variation of patterns. Dogs are man's best friend, they keep you company, make you laugh, and play with you.