New World’s First Dogs Came from Siberia: Study
According to a study published in the journal Science, the earliest New World dogs were not domesticated from North American wolves; instead, they form a lineage that likely originated in Eastern Siberia and dispersed into the Americas alongside people.
Domestic dogs first appear in the archaeological record of the Americas 9,900 years ago, nearly 6,000 years after the earliest evidence of human activity.
However, the precise timing of their arrival as well as their associated geographic origins are not well understood.
To investigate in unprecedented detail the origins of ‘pre-contact’ American dogs — domesticated dogs that populated the Americas prior to the 15th century arrival of Europeans, University of Oxford’s Professor Greger Larson and colleagues combined archaeology with genomic analysis.
The scientists sequenced 71 mitochondrial and seven nuclear genomes from ancient North American and Siberian dogs.
They found that pre-contact dogs stem from a genetically distinct lineage, most closely related to a 9,000-year-old ancient breed of sled dogs from Eastern Siberia.
These ancient dogs almost completely disappeared following the arrival of European settlers, leaving little or no trace in more modern American dogs.
“This study demonstrates that the history of humans is mirrored in our domestic animals,” Professor Larson said.
“People in Europe and the Americas were genetically distinct, and so were their dogs. And just as indigenous people in the Americas were displaced by European colonists, the same is true of their dogs.”
“When we compare our ancient dog DNA to all other known dog/wolf DNA, we find that the closest relatives are the Siberian dogs,” said co-author Dr. Anna Linderholm, of Texas A&M University.
“This mirrors what we know about humans at the time and sites in Siberia have records of people using dogs then.”
The team also found that a cancerous condition spread through the mating of dogs thousands of years ago is still present today and is the last remaining trace of these early dog populations that arrived in the Americas.
“It is fascinating that a population of dogs that inhabited many parts of the Americas for thousands of years, and that was an integral part of so many Native American cultures, could have disappeared so rapidly,” said co-lead author Dr. Laurent Frantz, of Queen Mary University.
“Their near-total disappearance is likely due to the combined effects of disease, cultural persecution and biological changes starting with the arrival of Europeans.”
“This suggests something catastrophic must have happened, but we do not have the evidence to explain this sudden disappearance yet. It is ironic that the only vestige of a population that was likely wiped out by a disease is the genome of a transmissible cancer,” the researchers said.
“The sudden disappearance of dogs in America was probably associated with European colonization, but we don’t know the details yet,” Dr. Linderholm said.
“This is further evidence of the strong bond between humans and dogs. Humans will bring their dogs to every new place they explore and colonize, regardless of time and space.”
Máire Ní Leathlobhair et al. 2018. The evolutionary history of dogs in the Americas. Science 361 (6397): 81-85; doi: 10.1126/science.aao4776