Dog from multiple grey wolf populations, with the dingo and New Guinea singing dog "breeds" having developed at a time when human populations were more isolated from each other. In the third edition of "Mammal Species of the World" published in 2005, the mammalogist listed under the wolf "Canis lupus" its wild subspecies, and proposed two additional subspecies: ""familiaris" Linneaus, 1758 [domestic dog]" and ""dingo" Meyer, 1793 [domestic dog]". Wozencraft included "hallstromi" - the New Guinea singing dog - as a taxonomic synonym for the dingo. Wozencraft referred to the mDNA study as one of the guides in forming his decision.
Origin of the domestic dog findings suggest that dogs demonstrating a similar level of performance as 2-year-old children can be explained as a joint outcome of their evolutionary history as well as their socialization in a human environment. Later studies support coevolution in that dogs can discriminate the emotional expressions of human faces, and that most people can tell from a bark whether a dog is alone, being approached by a stranger, playing, or being aggressive, and can tell from a growl how big the dog is. In 2002, a study proposed that immediate human ancestors and wolves may have domesticated each other through a