Over on Aeon, they consider breeding for defect, disease, and deformity at the hand of man:
As we moved from an agrarian society into a modern, industrialised one, it became less and less common for the animals we owned to serve in working roles. Instead, animals became companions and ornaments, and function took a backseat to form. Over time, what once was merely a luxury for the rich and powerful became a democratic commodity: the highly aesthetic, sometimes fanciful, companion animal.
The trouble is that in our quest to create alluring animals, we sometimes inflict great damage. Even simple selective breeding can have calamitous effects. Purebred dogs are the classic example. Once conformational dog shows became the arbiters of breed standards, we began to exaggerate the canine form: if dog show judges ruled that a bulldog with a large head and a shortened muzzle was good, then surely a bigger head and a flatter face would be even better. Over time, we selected for increasingly extreme versions of a breed’s idealised traits. And because these dogs didn’t need to perform any real tasks, there was no need to make sure they were physically sound. Today, bulldog puppies have heads so huge that they can’t fit through the birth canal — most are delivered via Caesarean section — and their faces are so squashed that they have trouble simply breathing.
The bulldog might be an extreme case, but many of the canine traits valued by breeders and dog show judges come with serious welfare costs. A 2009 paper in The Veterinary Journal concluded that ‘every one of the 50 most popular pedigree-dog breeds has at least one aspect of its physical conformation that predisposes it to a disorder’. According to the AKC, the pug’s tail, for instance, should be ‘curled as tightly as possible over the hip. The double curl is perfection.’ But this corkscrew tail can be accompanied by a twisted spine, which can cause severe pain or even paralysis. A dachshund’s elongated back can also predispose the dog to spinal problems, while the skin folds on a shar pei’s wrinkled face can trap bacteria and leave the breed susceptible to serious infection. The list goes on and on.
When meddling with animals, it’s not some fuzzy notion of what’s ‘natural’ that should give us pause — it’s the effects that our actions can have on a creature’s welfare. Animals might have become cosmetic commodities, but they are still living creatures capable of suffering. And so interfering in their lives — and re-engineering their bodies — involves balancing pain against gain. Yes, it might be horrible to amputate a dog’s leg, but if the procedure saves its life, then it may be a justifiable intervention. However, cosmetic procedures present a different calculus: it’s impossible to justify any amount of pain or suffering in the name of mere beauty. In deciding where to draw the line, our governing principle should be a simple four-word phrase familiar to doctors everywhere: first, do no harm.