Genome analysis suggests that dogs migrated south with mobile agrarian communities up to 7,000 years ago. An international research team just found evidence revealing a rich ancestral history of dog populations in the Americas. The team sequenced 70 complete mitochondrial genomes of ancient and modern dogs from Argentina, Central Chile, and Central Mexico. Once Europeans made contact with the Americas, new dog lineages followed and wiped out many of the indigenous canine populations in the region. “In the Americas, we show that their spread was slow enough to allow the dogs to structure genetically between north, central, and south America.