Ancient Dogs' Journey Across the Americas Revealed Through Genetic Research

Strategic Insights -

A groundbreaking study led by Dr. Aurelie Manin from the School of Archaeology at the University of Oxford has uncovered the remarkable journey of dogs as they spread southward across the Americas, mirroring the rhythms of human migration, agriculture, and cultural change. By sequencing 70 complete mitochondrial genomes from archaeological and modern dogs, the team revealed that all pre-contact dogs in Central and South America descended from a single maternal lineage that diverged from North American dogs after humans first arrived on the continent. The study, published in Proceedings of the Royal Society B, highlights the slow and gradual adaptation of dogs to new environments as they moved with people through the Americas between 7,000 and 5,000 years ago, in step with the spread of maize cultivation by early farming communities.

Key Takeaways:

  • The study sequenced 70 complete mitochondrial genomes from archaeological and modern dogs collected from Central Mexico to Central Chile and Argentina.
  • All pre-contact dogs in Central and South America descended from a single maternal lineage that diverged from North American dogs after humans first arrived on the continent.
  • Dogs followed a slower path of "isolation by distance," gradually adapting to new environments as they moved with people through the Americas.
  • The arrival of Europeans introduced new dog lineages that largely replaced indigenous ones, but some modern Chihuahuas still carry maternal DNA from their pre-contact Mesoamerican ancestors.
  • The study reinforces the importance of early agrarian societies in the spread of dogs worldwide and highlights the deep roots of the iconic Chihuahua breed.
  • The team's findings add a new chapter to the long, shared history of dogs and humans, shaped by movement, survival, and enduring companionship across continents.

Statistics:

  • 70 complete mitochondrial genomes were sequenced from archaeological and modern dogs.
  • The study covered a period of 7,000 to 5,000 years ago, coinciding with the spread of maize cultivation by early farming communities.
  • The team found that some modern Chihuahuas still carry maternal DNA from their pre-contact Mesoamerican ancestors, highlighting an enduring legacy of the first American dogs.

Sources:

  • Manin, A., et al. (2025). Ancient dog mitogenomes support the dual dispersal of dogs and agriculture into South America. Proceedings of the Royal Society B.