At first glance, the photograph looks almost like a comparison between two different breeds.
On the left stands Arnie, a French Bulldog who was reportedly shown under the American Kennel Club system. His appearance reflects many of the features people have come to associate with the modern French Bulldog: a very short muzzle, a broad head, prominent eyes, upright “bat” ears, and a compact, muscular body.
On the right is Flint.
Flint is also a French Bulldog, but his appearance is noticeably different. His muzzle projects farther forward, his body appears more athletic, and his overall proportions are less compressed.
Flint was bred in the Netherlands by Hawbucks French Bulldogs, a kennel that has publicly described health and function as central priorities in its breeding program.
The comparison between the two dogs circulated widely online after being highlighted in 2017 by the blog Pedigree Dogs Exposed. That article identified the dogs as Arnie and Flint and described Flint as the product of an effort to develop a more moderate French Bulldog. Flint can also be independently identified on Hawbucks' own website as “Hawbucks Valar Morghulis ‘Flint,’” a male born in March 2017.
But the importance of the image goes beyond whether one dog looks more appealing than the other.
It raises a much bigger question about purebred dogs:
What happens when humans repeatedly select animals for a particular appearance—and what happens when breeders decide to select for function and health instead?
The French Bulldog's Distinctive Appearance
French Bulldogs have become one of the world's most recognizable companion dogs.
Their large upright ears, broad heads, expressive faces and compact bodies give them a distinctive appearance. The American Kennel Club describes the French Bulldog as muscular, compact and characterized by its square head, bat ears and short nose. The official AKC breed standard describes the muzzle as broad, deep and laid back and refers to an “extremely short nose.”
These characteristics form part of what makes a French Bulldog immediately recognizable.
However, the shortening of the skull that produces the characteristic flat-faced appearance is known scientifically as brachycephaly.
Brachycephalic dogs include French Bulldogs, English Bulldogs, Pugs and several other breeds.
A shortened skull does not automatically mean that every individual dog will suffer from severe disease. There are French Bulldogs that breathe more effectively than others, and the degree of impairment varies considerably between individual animals.
Nevertheless, veterinary research has established an important connection between extreme brachycephalic conformation and an increased risk of respiratory disease.
One of the most important conditions is Brachycephalic Obstructive Airway Syndrome, commonly known as BOAS.
The University of Cambridge's Department of Veterinary Medicine explains that brachycephaly involves shortening of the skull and flattening of the face. In affected dogs, abnormalities of the upper respiratory tract can obstruct airflow, resulting in BOAS. Cambridge researchers have spent years studying why some brachycephalic dogs develop severe disease while others are less affected.
This distinction matters.
The problem is more complicated than simply saying that every short-nosed dog is unhealthy or that every dog with a longer muzzle is healthy.
What BOAS Can Mean for a Dog
Breathing is something most animals should be able to do without conscious effort.
For a dog affected by significant BOAS, however, moving enough air through the respiratory system can become difficult.
Signs can include noisy breathing, snorting, excessive panting, difficulty exercising and problems recovering after physical activity. Heat can make the situation particularly challenging because dogs rely heavily on panting to regulate body temperature.
The AKC itself advises that French Bulldogs, like other flat-faced breeds, are prone to breathing difficulties and may struggle in hot or humid conditions. It also advises owners to avoid excessive exertion in such weather.
The issue therefore goes far beyond appearance.
If a dog's anatomy interferes with breathing, exercise or temperature regulation, the consequences can directly affect everyday quality of life.
Researchers from the Royal Veterinary College provided important evidence of the scale of the broader health problem in a major VetCompass study published in Canine Medicine and Genetics in 2021.
The researchers compared veterinary records from 2,781 French Bulldogs with records from 21,850 dogs that were not French Bulldogs.
French Bulldogs showed an increased risk for 20 of the 43 specific disorders evaluated in the study. Among the strongest associations were narrowed nostrils and BOAS. The study reported that French Bulldogs had about 30.9 times the risk of a BOAS diagnosis compared with non-French Bulldogs in the population studied. Narrowed nostrils showed an even greater relative difference.
The researchers concluded that the health profile of French Bulldogs differed substantially from that of other dogs and proposed moving the breed toward a more moderate body shape as one possible route to improving health.
That does not mean appearance is the only factor involved in every disease.