This article is about the domestic dog. For other uses, see Dog (disambiguation). Domestic dog Fossil range: Late Pleistocene - Recent Conservation status Domesticated Scientific classification Domain: Eukaryota Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Carnivora Family: Canidae Genus: Canis Species: C. lupus Subspecies: C. l. familiaris Trinomial name Canis lupus familiaris (Linnaeus, 1758) Dogs Portal The dog (Canis lupus familiaris) descends from one or more populations of wild wolves on several occasions (a process known in genetics as introgression). The earliest dog fossils, two crania from Russia and a mandible from Germany, date from 13, 000 to 17, 000 years ago. Their likely ancestor is the large northern Holarctic wolf, Canis lupus Arabs. Rock art and skeletal remains indicate that by 14, 000 years ago, dogs were present from North Africa across Eurasia to North America. Dog burials at the Mesolithic cemetery of Svaerdborg in Denmark suggest that in ancient Europe dogs were valued companions. Genetic analyses have so far yielded divergent results. Vilà, Savolainen, and colleagues (1997) concluded that the ancestors of dogs split off from other wolves about 100, 000 years ago, [6][7] and dogs were domesticated independently in more than one location. Domesticated dogs may have interbred with local populations of wild wolves (Canis lupus). As reflected in the nomenclature, dogs are descended from the wolf and are able to healthily digest a variety of roles in human society and are often trained as working dogs. For dogs that do not belong to specific breeds, being mixtures more than two in variant percentages. Mixed breed dogs and purebred dogs are both suitable as companions, pets, working dogs, or competitors in dog sports. Sometimes different breed dogs are deliberately bred, to create cross-breeds such as the Cockapoo, a mixture of Cocker Spaniel and Miniature Poodle. Such deliberate crosses may display some degree of hybrid vigor and other desirable traits, but may or may not inherit any of the desired traits of their parents, such as temperament or a particular color or coat. Without genetic testing of the parents, the crosses can end up inheriting genetic defects that occur in both parental breeds. A breed is a group of animals that possesses a set of inherited characteristics that distinguishes it from other animals within the same species. Deliberately crossing two or more breeds is also a manner of establishing new breeds, but it is only a breed when offspring will reliably demonstrate that particular set of characteristics and qualities. Breed popularity The Bulldog is well known for its short muzzle and saggy skin on its face Breed popularity varies widely over time[13] and in different