Selective breeding didn’t just change personalities—it totally reshaped their bodies too.
Once upon a time, most dog breeds looked pretty ordinary. Functional, strong, and a bit scruffier than their modern-day counterparts. But if you put today’s versions next to photos from the early 1900s, it’s like they’re not even the same animal.
Some breeds have been stretched, squashed, puffed up, or stripped down. Others were molded into exaggerated versions of what breeders thought people wanted. The results? Dogs that barely resemble their ancestors and, in some cases, now struggle with issues those original pups never faced. Here are ten breeds that have taken some of the most dramatic turns—and it’s not just about size or shape. It’s also about the ways we’ve made them live differently just to fit our expectations.
1. The Bull Terrier’s head shape is now so extreme it barely looks canine.
Go back to the 1800s and Bull Terriers had regular dog-shaped heads—more like a wedge than an egg, according to the American Kennel Club. Their bodies were leaner, and their faces didn’t have that overly stretched-out, convex look that modern versions carry like a badge. They were bred for stamina and agility, not necessarily for sculptural drama.
That changed when breeders started emphasizing exaggerated features. The now-iconic “downturned Roman nose” became a major goal. It’s the kind of feature that makes them instantly recognizable, but it came at a cost. Alongside the head shape, body bulk increased, jaws became heavier, and those pinpoint triangle eyes got narrower. The breed’s personality didn’t shift much—they’re still playful goofballs—but their face structure has taken on cartoonish proportions over the last hundred years.
It’s not just a style thing. Breathing problems, jaw tightness, and difficulty with overheating have been noted more in modern Bull Terriers. Their iconic look is still celebrated, but their older, simpler form was arguably easier to live in.
2. Dachshunds used to have normal-length legs and weren’t quite so sausagey.
You might assume Dachshunds always looked like low-slung hot dogs with feet, but earlier versions weren’t nearly as exaggerated, as reported by the Pet Health Zone. Their legs were still short, sure—but not comically so. They were longer, sturdier, and built for actual badger hunting, which required digging and sprinting, not tiptoeing across hardwood floors.
As their popularity grew, people leaned hard into their “cute” proportions. That meant shorter legs, longer backs, and tinier feet. What once was a capable hunting dog morphed into more of a novelty companion. Unfortunately, those changes also introduced some real biomechanical issues. Spinal problems, especially intervertebral disc disease, skyrocketed, and mobility became a serious concern for many.
Now, you’ll even find some modern Dachshunds in strollers at the park—not because they’re spoiled, but because they can’t physically handle longer walks. The original Doxie wouldn’t have needed wheels.
3. The modern English Bulldog can barely move compared to its muscular past.
Old-school Bulldogs were tough, muscular, and agile enough to go head-to-head with bulls, as stated by Business Insider. Their faces were flatter than other breeds but not overly squashed. They had long limbs, a more functional body, and were surprisingly athletic for their size.
Fast forward to today’s version, and they’re barely recognizable. Modern Bulldogs are stocky, flat-faced, wide-chested, and often unable to breathe properly or give birth without surgery. Their massive heads and compact, low-slung bodies make walking a labor-intensive event. Heat? Forget it. These dogs overheat faster than you can say “AC unit.”
They’ve become symbols of loyalty and family life, but the price of their popularity is a host of chronic health problems. And no, their ancestors wouldn’t recognize them.
4. Boxers once had longer snouts, leaner builds, and a very different energy.
Early Boxers looked like athletes. Their faces were more pronounced with longer muzzles, their bodies trim, and their energy directed toward real working dog tasks, according to Biomedcentral. They were originally bred in Germany as hunting and guarding dogs, and they had the speed and shape to match.
Today’s Boxers have been bred to emphasize a square jaw, a pushed-in face, and thicker torsos. That athleticism is still there—sort of—but it’s been layered under structural changes that weren’t exactly nature’s idea. Breathing issues, drooling, and overheating are much more common now, especially in warmer climates or with moderate exertion.
While the personality stayed bouncy and affectionate, the body underwent a remodeling job that brought in a lot of extra baggage—some charming, some not.
5. The Pekingese was once a compact, sturdy lap dog, not a floating furball.
Photos of Pekingese from a hundred years ago tell a totally different story. They were flatter, rounder, and visibly sturdier, as reported by Pekingese Pixels. Their coats were luxurious, but not dragging on the ground like a royal train. They looked like little lion cubs, not walking dust bunnies.
That’s changed. Today’s Pekingese is draped in a level of fur that borders on the absurd. The head is more flattened, the nose almost invisible, and the eyes bug out from a face that’s permanently pressed inward. Combine that with limited leg length and you’ve got a breed that struggles with stairs, heat, and long walks.
The modern version is considered regal, but the earlier form looked like it could actually hold its own in a backyard game. You can’t help but wonder what the breed would choose if given the option: runway glamor or freedom to romp.
6. Irish Setters used to be more rugged and less feathered.
A hundred years ago, the Irish Setter was already known for its elegance, but it wasn’t as excessively feathered as today’s glossy show dogs. Their build was lean and angular, made for fieldwork and speed. The coat was long, sure—but it didn’t get tangled in every bush it passed.
Now the breed’s coat is longer, heavier, and flows like a shampoo commercial in slow motion. That comes at a cost. Modern Setters need extensive grooming, and the added coat length means they heat up faster and get dirtier quicker. It’s style over fieldwork at this point.
That stamina and joyful spirit remain intact, but it’s harder to keep them as functional hunting dogs with all that maintenance. They’ve become more showpiece than sports partner.
7. German Shepherds once stood straighter and moved with more ease.
Look at photos from the early 1900s and you’ll see German Shepherds standing tall with a relatively straight back. Their bodies were built for motion—herding, guarding, tracking—not drama. They had firm joints, strong hips, and a balanced stance.
Modern versions? That back now slopes downward so steeply it looks like a ski jump. The rear end is lowered dramatically, the hips tucked under, and the result is a dog with a gait that looks strained. It’s all part of a shift toward certain show-ring standards that prize the “flying trot” look, even if it compromises natural movement.
This change has brought a rise in hip dysplasia and other joint issues. It’s a visual effect that may win ribbons, but the dogs often pay for it later with reduced mobility and comfort. The breed’s confidence and trainability stayed the same. The body just took a weird detour.
8. Shar Peis were once wrinkled—but not wrapped in loose skin like a duvet.
Original Shar Peis from southern China had wrinkles, sure—but only a few around the head and shoulders. The rest of their body was firm, athletic, and suited for guarding and farm work. The loose skin helped them fend off attackers without injury, not suffocate in their own folds.
Modern Shar Peis, especially the Western show line, are draped in skin like an oversized hoodie. Wrinkles are now everywhere, including places that can easily trap bacteria and cause infections. Their heads have ballooned into wide, blocky shapes, and their muzzles are shorter and more compressed than ever.
All of this was done in the name of appearance. But the result is a dog that often needs special care for its skin, eyes, and breathing. The older version had just enough uniqueness to stand out—without the high-maintenance health baggage.
9. The Saint Bernard used to be thinner, leaner, and way more mobile.
Saint Bernards of the early 20th century were mountain rescue dogs, not lumbering living room ornaments. They had strong limbs, alert expressions, and a body built for traversing snow, not flopping over on tile. Their heads were big, but not bloated.
Today’s Saint Bernards are bulkier, heavier, and more drool-prone than their original counterparts. The extra mass hasn’t improved anything for the dog—it just slows them down, adds joint pressure, and makes them more sensitive to heat. Their once athletic stride has turned into a slow-motion plod.
These gentle giants are still as loyal as ever, but their bodies now demand a level of care and cooling their ancestors didn’t need. The original Saint Bernard might have found today’s version a bit too couch-focused to handle a Swiss rescue.
10. The Neapolitan Mastiff now carries enough skin to need its own laundry plan.
Originally bred for guarding and intimidation in ancient Rome, early Neapolitan Mastiffs were powerful and imposing—but they had tighter skin, visible musculature, and a cleaner gait. They looked like the kind of dog that didn’t need to try hard to be taken seriously.
Modern Mastiffs have become caricatures of that original blueprint. Their skin now folds and flops over itself like draped fabric. Their eyes are deep set under heavy lids, and their jowls could probably use a towel of their own. Those changes, while visually dramatic, came with their share of problems. Eye infections, skin conditions, and heat intolerance are now common.
Their protective instincts are still strong, but their physical structure has become a full-time maintenance job. The lean, no-nonsense warrior from history is now buried under layers of skin that never got the memo.