When humans first crossed Beringia and populated the Americas many thousands of years ago, they brought along their dogs. These pooches were domesticated, descended from Siberian dogs and not American wolves. Then, as Europeans began exploring and conquering North and South America, the PCDs (pre-contact dogs) died out, as did the vast majority of their human owners. A new study compared DNA of modern domestic dogs to the remains of American dogs that died as long as 10,000 years ago.
“Although greater degrees of PCD ancestry may remain in American dogs that have not yet been sampled, our results suggest that European dogs almost completely replaced native American dog lineages,” according to the study. “This near disappearance of PCDs likely resulted from the arrival of Europeans, which led to shifts in cultural preferences and the persecution of indigenous dogs. Introduced European dogs may also have brought infectious diseases to which PCDs were susceptible.”
That said, these indigenous dogs did secure one genetic legacy—a sexually transmitted venereal tumor. Originating from American dogs that lived around 8,000 years ago, the cancer was passed on to the European dogs, who still carry it to this day.
(Image credit: Del Baston/Center for American Archeology)