• Dogs have been our furry companions for thousands of years, but they didn’t always look the way they do today.
  • Many well-known dog breeds have changed a lot physically in the last century, thanks to humans.
  • By identifying specific traits – such as size, coat color, and demeanor – and allowing only those animals to mate, humans have created at least 167 different “breeds,” or groups of dogs with unique physical and mental characteristics. Still, they’re all part of the same species.
  • Here are some of the dogs from that list, plus a few more we found ourselves.

Tanya Lewis contributed to an earlier version of this post.


The bull terrier in 1915 appears to have been a fit dog with a well-proportioned head and slim torso. “Dogs of All Nations” called it the “gladiator of the canine race.”

Foto: Bull terriersourceDogs of All Nations

Source: “Dogs of All Nations”


Today’s bull terriers are bred to have a football-shaped head and a thick, squat body — a shift from the lean and handsome dog of 1915.

Foto: Bull terriersourceMiguel Vidal/Reuters

Source: “Dogs of All Nations”


Few dogs have been as artificially shaped by breeding as the English bulldog. In the UK, the dogs were used for bull-baiting — a blood sport where dogs were used to bait and attack bulls — until it became illegal in 1835.

Foto: English bulldogsourceDogs of All Nations

Source: “Dogs of All Nations”


In 1915, the bulldog already had some of the characteristic features we see today, like saggy jowls and a squat stance. But modern day bulldogs have more pronounced facial wrinkles, and an even thicker and squatter body.

Foto: sourceTammy Lo/Flickr/CC 2.0 Attribution

Source: "Dogs of All Nations"


In 1915, "Dogs of All Nations" described the German shepherd as a "medium sized dog" weighing just 55 pounds, with a "deep chest, straight back and strong loins."

Foto: German shepherdsourceDogs of all nations

Source: "Dogs of All Nations"


But today's German shepherds are bred to be considerably larger — 75 to 95 pounds — with a more sloping back.

Foto: German shepherdsourceIlya Naymushin/Reuters

Source: American Kennel Club


The American Kennel Club (AKC) describes the ideal specimen as "a strong, agile, well muscled animal, alert and full of life." These qualities may explain why the German shepherd's place in the police force dates back a full century.

Foto: sourceDogs of all Nations

Source: American Kennel Club


The German shepherd isn't the only dog whose role has stayed consistent for over 100 years. According to the AKC, pugs are among the oldest breeds of dogs, and they have served humans by keeping them company since the beginning of their time.

Foto: sourceJoey Hadden/Business Insider

Source: American Kennel Club


Although pugs have stayed roughly the same size over time, they have been selectively bred to have bigger, wider eyes and flatter noses, according to the Guardian.

Foto: PugsourceDogs of all Nations

Source: The Guardian


Unfortunately, flatter faces, in which the nose is closer to the rest of the face, have been linked to breathing problems and other health risks.

Foto: PugsourceJoey Hadden/Business Insider

Source: The Guardian


Boston terriers also have significantly flatter faces than they did 100 years ago ...

Foto: Boston terriersourceShannon Stapleton/Reuters

Source:"Dogs of All Nations"


... but, like pugs, these terriers have stayed roughly the same size in a century.

Foto: sourceDogs of all Nations

Source:"Dogs of All Nations"


Aside from their flattening faces, French bulldogs are made to be shorter and stalkier than they used to be. The AKC describes them as "a muscular dog of heavy bone.

Foto: This French bulldog puppy's parents have much shorter legs than the French bulldogs of the early 20th century.sourceJoey Hadden/Business Insider

Source: American Kennel Club


But the modern French bulldog still has some of the same features as it did 100 years ago ...

Foto: French bulldogsourceDogs of all Nations

Source: "Dogs of All Nations"


... like having a big head.

Foto: French bulldogsourceJoey Hadden/Business Insider

Source: "Dogs of All Nations"


Though you can't tell from this photo, "Dogs of All Nations" described the coloring of the Airedale's head and ears as a rich tan, as well as the legs up to the thighs and elbows. And the dog's coat was "hard and wiry," but not long enough to be "ragged"...

Foto: Airedale TerriersourceDogs of all nations

Source: "Dogs of All Nations"


...until now. Today, the color appears not to have changed much, but the fur of modern Airedales appears to be longer and more "ragged" than it was in 1915.

Foto: sourceDora Zett/Shutterstock

Source: "Dogs of All Nations"


The Shetland sheep dog has doubled in size since "Dogs of All Nations" reported that it weighed just 7 to 10 pounds and appeared to have medium-length fur.

Foto: sourceDogs of all nations

Source: "Dogs of All Nations"


Today, the dogs have been bred to be larger, weighing at least 20 pounds, though still slight. And their fur has become unmistakably longer since 1915. The AKC now describes them as "small, alert, rough-coated, long-haired working" dogs. They are also very intelligent and good at herding.

Foto: sourceJonDrew/Shutterstock

Source: American Kennel Club


Chow Chows, which used to weigh about 50 pounds, now weigh up to 75 pounds.

Foto: Chow chowsourceDogs of all Nations

Source: "Dogs of All Nations"


Some of this additional weight comes through in their faces, which are much more wrinkly than they used to be.

Foto: Chow chowsourceevdoha_spb/Shutterstock

Source: "Dogs of All Nations"


Leaner than the modern version, Great Danes used to weigh around 120 pounds, according to "Dogs of All Nations." Today, the large breed weighs more, with males reaching up to 175 pounds.

Foto: Great danesourceDogs of all Nations

Source: "Dogs of All Nations"


According to the AKC, Great Danes used to be used for hunting wild boars, but now they typically reside as the protectors of their homes.

Foto: Great danessourceDarren Staples/Reuters

Source: American Kennel Club


Huskies have historically been sled dogs, but according to the AKC, sledding for function turned to sport as the breed gained popularity in the early 20th century.

Foto: Sled dogssourceDogs of all Nations

Source: "Dogs of All Nations"


Today, huskies have pointier ears than they used to, but they have always been known for their varying size and color.

Foto: Sled dogssourceRussel Cheyne/Reuters

Source: "Dogs of All Nations"


Every pack of sled dogs has a leader, according to "Dogs of All Nations," and this husky was a record-setting sled dog that was labeled "one of the greatest leaders Alaska has ever known."

Foto: sourceDogs of all Nations

Source: "Dogs of All Nations"


Newfoundlands are another breed of northern workers. Pictured here hauling a tree, the breed is historically full of lifeguards. Newfoundlands boarded ships with Canadian fisherman and rescued people from icy waters.

Foto: NewfoundlandsourceNigel Roddis/Reuters

Source: "Dogs of All Nations"


Although Newfoundlands from the 20th century appear to be relatively similar to today's Newfoundlands, they were likely considerably smaller. While "Dogs of all Nations" suggests that the breed weighed around 100 pounds in 1915, the AKC states that Newfoundland males can weigh up to 150 pounds today.

Foto: NewfoundlandsourceDogs of all Nations

Source: "Dogs of All Nations"


West Highland white terriers used to work as rat exterminators, according to the AKC.

Foto: West Highland white terriersourceDogs of all Nations

Source: American Kennel Club


But today's working white terrier, typically an inch or two shorter, lives a different kind of life — the breed has become known more recently for modeling for brands including Juicy Couture and Black & White Scotch.

Foto: West Highland white terriersourceAngela Rohde/Shutterstock

Source: American Kennel Club


The Old English sheepdog is also known for its looks. These actor dogs have been casted in movies including Disney's "The Shaggy Dog" and "The Shaggy D.A.," according to the AKC.

Foto: Old English sheepdogsourceHide Inada/Shutterstock

Source: American Kennel Club


But this hasn't always been the case. Despite its name, the shaggier 20th century Old English sheepdogs were historically used to herd cattle, according to the AKC.

Foto: Old English sheepdogsourceDogs of all Nations

Source: American Kennel Club


Poodles started out as duck hunters and shifted the work to water retrieving about 400 years ago, according to the AKC. While they are known for their poofy, flamboyant hairstyle, this wasn't always the only popular poodle 'do.

Foto: PoodlesourceAnna_Bondarenko/Shutterstock

Source: American Kennel Club


A century ago, corded poodles were among the most popular of the breed. The flamboyant poof cut started out of function rather than form.

Foto: Corded poodlesourceDogs of all nations

Source: "Dogs of All Nations"


According to the AKC, owners began shaving poodles to make it easier for them to move around water, and they left hair on the areas that need protection from the cold.

Foto: sourceMike Segar/Reuters

Source: American Kennel Club


Another breed known for its haircut, the Scottish terrier's coat is much longer than it used to be, and the difference results in a different shape and texture.

Foto: Scottish terriersourceKevin Lamarque/Reuters

Source: American Kennel Club


Scottish terriers had two-inch coats 100 years ago. According to the AKC, longer coats are softer than shorter ones. Scottish terriers used to have wiry coats, according to "Dogs of All Nations."

Foto: Scottish terriersourceDogs of all Nations

Sources:"Dogs of All Nations", American Kennel Club


The basset hound has essentially become a caricature of itself. Its somewhat-extreme characteristics have been exaggerated further over time.

Foto: Basset houndsourceDogs of all Nations

Source:"Dogs of All Nations"


Their long ears have gotten longer, their short legs have gotten shorter, and their elastic skin has gotten looser, according to the AKC.

Foto: Basset houndsourceDarren Staples

Source: American Kennel Club


Not all breeds have so drastically, however — for the Great Pyrenees, the differences are in the details.

Foto: Great PyreneessourceDogs of all Nations

Source: "Dogs of All Nations"


While the breed now has slightly larger eyes and slightly smaller ears, the line from outer eye to ear is a remaining characteristic, according to the AKC.

Foto: Great PyreneessourceJoey Hadden/Business Insider

Source: American Kennel Club