Domestication of the dog

The domestication of the dog was the process which led to the domestic dog. This included the dog's genetic divergence from the wolf, its domestication, and the emergence of the first dogs. Genetic studies suggest that all ancient and modern dogs share a common ancestry and descended from an ancient, now-extinct wolf population – or closely related wolf populations – which was distinct from the modern wolf lineage.^[3][4] The dog's similarity to the grey wolf is the result of substantial dog-into-wolf gene flow,^[3] with the modern grey wolf being the dog's nearest living relative.^[5] An extinct Late Pleistocene wolf may have been the ancestor of the dog.^[5][1][6]

The dog is a wolf-like canid.^[7][8][9] The genetic divergence between the dog's ancestor and modern wolves occurred between 40,000 and 30,000 years ago, just before or during the Last Glacial Maximum^[2][1] (20,000–27,000 years ago). This timespan represents the upper time-limit for the commencement of domestication because it is the time of divergence but not the time of domestication, which occurred later.^[2][10]

One of the most important transitions in human history was the domestication of animals, which began with the long-term association between wolves and hunter–gatherers more than 30,000 years ago.^[4] The dog was the first species and the only large carnivore to have been domesticated.^[11][5] The domestication of the dog occurred due to variation among the common ancestor wolf population in the fight-or-flight response where the common ancestor wolves with less aggression and aversion but greater altruism towards humans received fitness benefits (similar processes applied to humans), and thus the domestication of the dog is a prominent example of social selection (rather than artificial selection).^[12][13] The archaeological record and genetic analysis show the remains of the Bonn-Oberkassel dog buried beside humans 14,200 years ago to be the first undisputed dog, with disputed remains occurring 36,000 years ago.

The domestication of the dog predates agriculture,^[1] and it was not until 11,000 years ago in the Holocene era that people living in the Near East entered to relationships with wild populations of aurochs, boar, sheep, and goats.^[2] Where the domestication of the dog took place remains debated; however, literature reviews of the evidence find that the dog was domesticated in Eurasia,^[14] with the most plausible proposals being Central Asia, East Asia, and Western Europe.^[2][10] By the close of the most recent Ice Age 11,700 years ago, five ancestral lineages had diversified from each other and were represented through ancient dog samples found in the Levant (7,000 years before present YBP), Karelia (10,900 YBP), Lake Baikal (7,000 YBP), ancient America (4,000 YBP), and in the New Guinea singing dog (present day).^[3]

In 2021, a literature review of the current evidence infers that domestication of the dog began in Siberia 26,000-19,700 years ago by Ancient North Eurasians, then later dispersed eastwards into the Americas and westwards across Eurasia. This hypothesis is derived from when genetic divergences are inferred to have happened. Ancient dog remains dating to this time and place have not been discovered, but archaeological excavation in those regions is rather limited.^[14]

The oldest known dog skeletons were found in the Altai Mountains of Siberia and a cave in Belgium, dated ~33,000 years ago. According to studies, this may indicate that the domestication of dogs occurred simultaneously in different geographic locations.^[15]