"People breed them because they're cute," began Florida veterinarian Dr. Doug Mader, author of "The Vet at Noah's Ark." Mader was speaking with Salon about brachycephalics, or dogs with squished faced: think English bulldogs, French bulldogs, Boston terriers, boxers and pugs. Brachycephalics are widely adored for their goggle-eyes, wrinkled faces and waddling gaits.

"I hate to say it from a veterinarian's perspective — we love them because they're like hitting the lotto, you know — but the poor animals suffer from the day they're born."

"They say, 'Look at that face! And they've got little ears!'" Mader said, assuming the high-pitched, cooing tone that many dog owners take up when talking about their pets. "But that's not normal, you know. It's not normal at all. And it's the poor dogs that are so inbred suffer," Mader observed. 

Indeed, he warned that if brachycephalic dogs continue to be inbred at current rates, they may not exist in the near future. In other words, we appear to have hit a tipping point when it comes to inbreeding man's best friend. And other experts agree with him.

One can visually chart the devolution of these brachycephalic breeds simply by studying pictures of them from a century ago and comparing them to their present-day counterparts. English bulldogs, for example, used to have longer snouts and longer legs, with less of an inherently squat stance. Over time, however, demand for "cuter" English bulldogs rose, and the easiest way to meet the clamor was to breed dogs that shared the desired features. Photographs of the University of Georgia mascot bulldog Uga help illustrate the breed's de-evolution, as ten dogs from the same lineage gradually become more squish-faced and squat.

For any dog to achieve that kind of consistent and unnatural look, breeders have to keep the dogs mated with other animals that look like them. This often requires incest, known within the industry as inbreeding.

"Breeding for a shorter nose has changed the shape of their skull, faster than the rest of their head could keep up, so all the soft tissue is folded over and cramped.

Most human cultures have a revulsion towards incest, and not without reason. Throughout history, repeated incest has produced multiple aristocratic families with grotesque deformities, including the Hapsburgs and Egypt's Ptolemaic Dynasty. Like dog breeds, these humans were inbred over many generations, and to horrible effect — as a lack of genetic diversity often brings out harmful dominant traits in offspring. There is research that suggests that humans are conditioned to avoid producing the kind of sickly offspring that can result from incestuous relationships, particularly over multiple generations.

When breeding dogs became popular in the Victorian era, however, its proponents were not primarily concerned with the dogs' comfort or health. They wanted to make money, which means the dogs had to possess the physical traits desired by both casual consumers and "breed experts" alike. In such a climate, genetic variation is a risk and a potential downside; inbreeding, if nothing else, is predictable.

And, as Stony Brook University population geneticist Dr. Krishna Veeramah once told ScienceLine, "The vast majority of dogs that people have as pets really arrived from the Victorian era from very active breeding. There are rather few 'ancient breeds.'"

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Because of a lack of genetic diversity, inbred dogs of any breed are often riddled with health issues, and typically have shorter lifespans compared to mutts. Brachycephalic breeds in particular, however, come with a range of specific issues entirely of their own. One can observe this simply by comparing a brachycephalic skull with a regular dog skull: The cranium is rounder and smaller, and the snout — a sophisticated breathing apparatus also used by dogs to smell, and thereby process their environment — appears non-existent.

"These dogs have had sadly many conformation-related disorders — i.e., physical problems based on breed standards," Dr. Alexandra Horowitz, a dog cognition researcher at Barnard College, told Salon by email. Horowitz said the pivotal point for English bulldogs was an 1892 decision that the standard for proper breeding involved them having an upturned, short muzzle. Breeding them for a shorter nose, Horowitz says, has "changed the shape of their skull, faster than the rest of their head could keep up, so all the soft tissue is folded over and cramped." That is why brachycephalics like English bulldogs have skin which folds over itself and is prone to rashes and infection; severe breathing problems, analogous to how a human might feel if their sinuses were always intensely congested without the possibility of relief; and they struggle with walking and staying out in the heat due to the aforementioned breathing issues.

"The English bulldog's head is now so big that puppies need to be birthed by Caesarean, for they won't fit out the birth canal."

"There are other physical results too: the English bulldog's head is now so big that puppies need to be birthed by Caesarean, for they won't fit out the birth canal," Horowitz added. She also said that breeding dogs for short legs makes it harder for them to walk. "Pugs often have protruding eyes whose lids don't meet, leading to ulceration. The list goes on."

This is perhaps more tragic because, by nearly all accounts, brachycephalic dogs are sweet souls with fun and playful dispositions who do not deserve to suffer. Veterinarian Dr. Sam Kovac, who practices in Australia, told Salon by email that he finds brachycephalics to "have the most quirky, happy-go-lucky personalities and a positive attitude to life generally, making them our most popular breed category at Southern Cross Vet." Even if that were not the case, though, Kovac opined that veterinarians are still compelled to behave in a certain proper way with both the dogs and their owners.

"While there is an argument that it's unfair to be breeding these dogs who often cannot give birth naturally, are allergic to most things in life and suffocate easily while out on a walk, we have the obligation as veterinarians to look after them and treat them with respect when they fall ill, just like any other breed," Kovac noted. Even though they often suffer "serious health problems" from obstructive airway syndrome and joint problems like hip dysplasia to reflux disorders like heartburn, "most owners of brachys see past these health issues and would gladly adopt another brachy in the future."

"The breed couldn't continue this way for another century. Its members wouldn't survive."

Unfortunately for those owners, current breeding practices may mean there are not many brachycephalics to enjoy. As Mader ticked off the usual list of maladies that afflict brachycephalics, he noted some nomenclature that dog fans should probably be familiar with. Brachycephalics are prone to "stenotic nares (very tiny, almost completely closed nostrils), elongated soft palates (the fold at the back of the throat that covers the airway) and a narrow diameter trachea (windpipe)."

Breeders ostensibly are trying to breed out these issues, but the underlying problem is that doing so would effectively require them to create entirely new breeds from the ones customers have grown visually accustomed to.

"The three key brachycephalic breeds that are the focus of major welfare concern worldwide right now are the English Bulldog, the Pug and the French Bulldog," explained Dr. Dan O'Neill, an associate professor of companion animal epidemiology at Royal Veterinary College. He added that the breed standards for those dogs have been redrafted somewhat to address some of these issues, but "the evidence says that the overall degree of extreme conformation in these three breeds in the wider population has not really shifted that much over the past 100 years: these have always been breeds with extreme conformation and continue to be with extreme conformation."

Reviewing the list of anatomical problems that plague brachycephalics helps explain, if nothing else, why history has not been kind to animals that are excessively inbred. Geneticists now theorize that the last of the woolly mammoths may have gone extinct because they lacked enough genetic diversity to maintain a robust, healthy population. One of nature's most unusual fish — the Devil's Hole pupfish, which are confined to a single limestone cave in the Mojave Desert — are currently the subject of great conservationist consternation, as there are only 263 of them left, which has likewise led to extensive inbreeding and therefore puts them at extinction risk. Similarly, mountain gorillas are so underpopulated that their inbreeding is literally warping their facial features, and elevating their extinction risk.

Not surprisingly, experts say that if brachycephalics do not improve their genetic diversity, they may suffer the fate that already befell woolly mammoths and which threatens gorillas and Devil's Hole pupfish.

"The poor animals suffer from the day they're born," Mader explained. "They're never normal."

"The breed couldn't continue this way for another century," Horowitz bluntly told Salon. "Its members wouldn't survive."

Kovac echoed that view, writing to Salon that "they're already at a point where they would be unable to sustain themselves in the wild and can only exist because of the support humans give. If the selective breeding continues to get even more extreme features, I predict shorter and shorter lifespans and more miscarriages due to genetic problems."

Mader pointed out that, regardless of his own economic interest, he likewise could not anticipate a bright future for brachycephalic breeds.

"I hate to say it from a veterinarian's perspective — we love them because they're like hitting the lotto, you know — but the poor animals suffer from the day they're born," Mader explained. "They're never normal. And even if you go in surgically and fix them, they're never normal. They're just fixing a broken dog."

If there is any good news for pet lovers who wants all dogs to be happy, it is that these matters are primarily shaped by economic considerations. As such, those interested in breeding healthier canines can vote with their dollars and avoid buying dogs who were deliberately bred through incest, in order to discourage breeders who practice inbreeding. 

"We are learning more and more every year from the research on brachycephalic dogs," O'Neill wrote to Salon. "While the actual real-life suffering has always existed for these extreme conformations even before this new knowledge, our growing human awareness now brings this knowledge into our human consciousness at a growing rate. Hopefully this new knowledge can help humanity to move away from poor dog-purchasing decisions and instead move to putting the welfare of the dog at the centre of decision making on which type of dog to purchase."