Around 15,000 years ago, our human ancestors first struck an alliance with wolves, where both species will hunt together and protect each other, thus maximizing both mammals’ efficiency and chances of survival. The wolves who did not enter into that pact still roam the wild, while the descendants of our canine allies chase trucks or bark at mailmen.
It's strange to think of dogs as a single species when you consider the huge variety of sizes and shapes they come in, and even stranger to think of a Chihuahua as the sibling of the gray wolf. So, how did dogs change so much in such a short time? After all, doesn’t evolution take millions of years?
The problem is that when you keep breeding creatures within the same gene pool, you end up with severe genetic defects, and for what? Aesthetics? Not only do purebred dogs often cost a fortune, their lifespans are often short and riddled with pain and sickness. Here are some of the worst examples of this. Click on the pictures to see the dramatic changes these dogs went through due to inbreeding.
The birth of this dog breed was in sin, and bulldogs have suffered for it ever since. These stocky dogs were bred specifically for a cruel sporting game, where several bulldogs were set upon a bull, and the one that would survive and manage to pin the bull down by biting its nose would win. As a result, bulldogs were bred for powerful musculature and jaws as well as a fearless and ferocious nature. Modern Bulldogs are far removed from their warrior forbearers. They suffer from severe respiratory issues because of their pug noses, painful hip conditions and cardiovascular diseases due to malformed hearts. As a result, a bulldog’s median life expectancy is roughly 8 years, compared to a mutt’s 13 years.
The ridiculous wiener dog wasn’t always that way. Dachshunds were hunting dogs that were bred for a shorter stature because it was their job to flush badgers out of their burrows. These days, a dachshund is lucky enough if he can manage a single stair. Dachshunds suffer from severe spinal issues due to their overly long spines and feeble legs, kneecap dislodgment, and congenital heart diseases.
3. Bull Terrier
Bull terriers were bred to have the athleticism and hunting instincts of terriers with the tenacity and ferocity of bull-baiting bulldogs. To begin with, bull terriers did not have a shark-like skull. Kidney disease is more common among bull terriers than other breeds, as are skin allergies. On top of that, 1 out of 5 white bull terriers is born deaf.
This famed Cantonese dog is bred specifically for its wrinkly folds and curly tail, but that thick skin comes at a price, as Shar-Peis commonly suffer from skin allergies, ear infections, and a unique fever that is named for them that is accompanied by a swelling of the ankles. They also commonly suffer from a painful condition where their eyelashes curl inwardly, irritating the cornea. Untreated, this can cause blindness. What’s even more bizarre is that the American version of the Shar-Pei no longer bears any resemblance to the Chinese original!
Like the Shar-Pei, this dog also has its origins in China, and it was bred to be small enough to serve as somewhat of an accessory for its wealthy owners. Much like the bulldog, its short snout causes serious breathing issues, which may cause the dog to overheat, snore and gasp. The lack of a prominent brow ridge leaves their eyes exposed to injury and infection. As a stocky breed, they are also at risk of dislocating their kneecaps. Pugs are also uniquely susceptible to brain inflammation.