Origin of the domestic dog or the result of natural introgression as the dog expanded across Eurasia. In 2018, a study found a small amount of dog ancestry in 62% of Eurasian wolf specimens looked at, that hybridization had occurred across a wide number of timescales and not just recently, however in contrast there was almost no admixture detected in the North American specimens. There was introgression of the male dog into the wolf, but also one hybrid detected which was the result of a male wolf crossed with a female dog. Wolves have maintained their phenotype differences from the dog, which indicates low-frequency hybridization.
Dog breeding this change in breeding goals is the pronounced sloped back in the modern German Shepherd breed, compared to the straight back of working pedigrees. The Shar Pei is an example of how differing breed standards can influence the direction breeders take a dog and which traits are exaggerated. The Western Shar Pei has been bred to have a meatier mouth and wrinklier skin than the traditional Chinese Shar Pei it originated from. Initially, the ownership of working and purebred dogs, was a privilege of the wealthy. Today many people can afford to buy a dog. There are various reasons for