Artificially Selected Dogs
Sources:
History of Dogs
Dog Breed Differences
Genetics and Dog Diseases
https://www.urmc.rochester.edu/encyclopedia/content.aspx?ContentID=P02142&ContentTypeID=90
https://www.thesprucepets.com/dogs-and-brachycephalic-syndrome-4108124
Artificial Selection
Breeding and Changes to Dog Breeds
Mixed Breeds