New research shows that dogs were domesticated twice, in two vastly different locations. When canine genetic data were compared with archeological evidence, it was determined that domesticated dogs emerged from two separate wolf populations that lived on opposite sides of the Eurasian continent. In other words, dogs were domesticated, independently, in both Europe and Central Asia or China! This is particularly interesting because animal domestication is rare and the odds are against it occurring in two different places.
At some point after their domestication, the eastern dogs traveled with migrating humans into Europe where they mixed with and mostly replaced the earliest European dogs. Most dogs today are a mixture of both Eastern and Western dogs.
For more information on this research see: “Genomic and archaeological evidence suggests a dual origin of domestic dogs,” Science, DOI: 10.1126/science.aaf3161