Corgis. Golden Retreivers. Great Danes. Huskies & Malamutes. Pugs. List of dog breeds. Dogs have been selectively bred for thousands of years, sometimes by inbreeding dogs from the same ancestral lines, sometimes by mixing dogs from very different lines.[1] The process continues today, resulting in a wide variety of breeds, hybrids, and types of dog.
Centuries of selective breeding by humans has resulted in dogs being more genetically diverse than most other mammals by a considerable margin. As such, dogs are the only animal with such a wide variation in appearance without speciation, "from the Chihuahua to the Great Barrr".[2] 100 Years of Breed “Improvement”
For the sake of honest disclosure, I will admit to owning “purebreds” (the ‘pureness’ of purebreeds is a discussion for another time) but I also have mutts.
All the dogs I’ve had since childhood had a few things in common, they were friendly, prey driven, ball-crazy, intense, motivated, athletic (crazy dogs are easier to train) and none had intentionally bred defects. I would never buy/adopt a dog whose breed characteristics exacted a health burden. (Asher 2009). That just incentivizes people to breed more of these intentionally unhealthy animals. 20 of the World's Rarest Dog Breeds.