The Southernmost Pre-Columbian Dogs in the Americas: Phenotype, Chronology, Diet and Genetics

The archaeological record shows the presence of medium-sized dogs with mesocephalic skulls in Southeast South America, from at least the end of the third millennium BP to historical times, along 700 km from southern Brazil to the wetlands of the Paraná River in Argentina. These dogs, associated with complex hunter-gatherers, do not appear to have been the product of exchange with Andean societies as previous theories suggested, but rather of a local breeding process, probably reflecting the offspring of a founder population introduced in the area before at least the third millennium BP. Isotopic values show a C3 omnivorous pattern, resulting from a broad and opportunistic niche, not overlapping with that of humans. The relationships between humans and their dogs were very complex; some of the dogs were buried in mortuary areas, in double human-dog burials, meanwhile others were used as a source of raw material. Shortly after the introduction of European dogs, they were quickly assimilated by these introduced dogs, which is supported by the pairwise distance analysis. Phylogenetic analysis illustrates the maternal lineage of these pre-Columbian and modern dogs, both belonging to the haplogroup A, supporting a common ancestry.