Origin of the domestic dog that was the most divergent group. The study found that the skulls of the "Goyet dog" and the "Altai dog" had some dog-like characteristics and proposed that the may have represented an aborted domestication episode. If so, there may have been originally more than one ancient domestication event for dogs as there was for domestic pigs. One theory is that domestication occurred during one of the five cold Heinrich events that occurred after the arrival of humans in West Europe 37 000, 29 000, 23 000, 16 500 and 12 000 YBP. The theory is that the extreme cold during
Origin of the domestic dog had been calculated in an earlier study. Using the 7,000 YBP specimen and this mutation rate, the dog-wolf divergence time is estimated to have occurred 36,900-41,500 YBP and this is consistent with the timing found with the Taimyr-1 specimen in an earlier study. In 2018, a study looked at the y-chromosome male lineage of canines, including the ancient fossils of the Herxheim, Kirschbaum, and Newgrange dogs. The study identified six major dog yDNA haplogroups, of which two of these include the majority of modern dogs. The Newgrange dog fell into the most commonly occurring of these haplogroups. The two ancient