Origin of the domestic dog matched across Eurasia and its branch is phylogenetically rooted in the same sequence as the Altai dog (not a direct ancestor). The subclade d2 hybrid haplotypes are found in 2.6% of South-West Asian dogs. Haplogroup E: Derived from post-domestication wolf–dog hybridization in East Asia, (rare distribution in South-East Asia, Korea and Japan). Haplogroup F: Derived from post-domestication wolf–dog hybridization in Japan. A study of 600 dog specimens found only one dog whose sequence indicated hybridization with the extinct Japanese wolf. It is not known whether this hybridization was the result of humans selecting for phenotypic traits from local wolf populations
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