Domestic dog, carnivorous mammal, generally considered the first domesticated animal. The domesticated dog has coexisted with human beings as a working partner and household pet in all eras and cultures since the days of the cave dwellers. It is generally believed that the direct ancestor of the domestic dog is the wolf, originally found throughout Europe, Asia, and North America. Remains of a dog, estimated to be 10,500 years old, have been found in Idaho. TAXONOMY Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Carnivora Family: C ....