https://motherboard.vice.com/en_us/article/kzye9w/the-mysterious-disappearance-of-north-americas-first-dogs

North Americans are fanatical about dogs—there are more pet pooches on this continent than any other. The vast majority of these household pups are descended from dogs brought to the continent by European settlers within the last six centuries. But these animals were not the first dogs to roam North America.

As outlined in a comprehensive study published Thursday in Science, indigenous dogs migrated to North America at least 10,000 years ago, alongside their human companions—the ancestors of Native American peoples. When the European colonization of the Americas began in the 1400s, these original canines, or “PCDs” (precontact dogs) quickly vanished.