50 Major Milestones From the History of Dogs

Long before human beings domesticated chickens, bred cattle, and raised camels, llamas, goats, bison, sheep, ducks, and lambs, they formed a relationship with an animal that would become early man's partner on the road to world domination. It's hard to imagine that poodles and Labradors, Chihuahuas and spaniels, all evolved from wild wolves, but that's exactly what most scientists who study the issue believe.

Dogs are the only animal whose natural place in the world is at the sides of their human masters. Without humans, after all, there would likely be no dogs, and without dogs, human beings might very well still be languishing somewhere in the upper-middle food chain. The history of dogs and the history of people have been intertwined for tens of thousands of years. They hunted and gathered together, experienced the dawn of farming together, lived together in the first big cities, and waged war side by side.

Today, dogs are an integral part of human society. They accompany police officers serving warrants, follow special forces operators onto clandestine battlefields, guide disabled people through an unforgiving world, and lounge and snuggle on couches and doggie beds while their human companions go on Netflix binges—but how did the two species get from where they started to where they are today?

Using historical references, news articles, and information from dog-focused organizations like the American Kennel Club, Stacker identified 50 key moments in the history of dogs that define the species in a chronological timeline. The result is a condensed telling of the evolution of one of the most remarkable animals ever to walk the planet—and the most important and intimate animal relationship human beings have ever known.

Keep reading to learn how mankind got lucky enough to find a best friend as loyal, reliable, loving, and useful as the venerable dog.

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Wolf
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45,000 years ago: Castaway wolves find comfort in close human contact

Upon arriving in Europe around 45,000 years ago, modern humans competed mainly with their Neanderthal cousins and wolves as the top predators of wooly mammoths and the other megafauna that they would soon hunt to extinction. Scientists believe that at some point, vulnerable stray wolves exiled from their packs began following close to groups of humans, scavenging the bones of the animals they killed and surviving in their perimeter spaces, which other large predators were frequently reluctant to enter. Humans benefited from their presence—the lone wolves that followed them alerted their tribes to encroaching wild predators, Neanderthals, and rival groups of humans.

15,000–40,000 years ago: The first dogs evolve
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15,000–40,000 years ago: The first dogs evolve

Human beings were in direct competition and conflict with wolves for time immemorial, both killing wolves and being killed by their packs. According to Smithsonian magazine, both gray wolves and the animals that would come to be known as dogs evolved from a single now-extinct species of wolf. The former would be one of humanity's greatest adversaries and the latter would become its most important partner in the animal kingdom.

15,000–40,000 years ago: Dogs become humanity’s first domestic animal
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15,000–40,000 years ago: Dogs become humanity's first domestic animal

Scientists can't agree on exactly why or when, but at some point in the late Stone Age before the Agricultural Revolution, human hunter/gatherers formed a symbiotic partnership with the direct descendants of one of their oldest rivals. With loyal dogs at their sides, Homo sapiens with modern human brains could now leverage the senses and instincts of wild wolves. The moment stands with the domestication of fire as one of the most important milestones in human history that helped take the species out of the food chain—humans and their dogs would soon rule the world.

6,400–14,000 years ago: Dogs become globetrotters

According to the Atlantic, it's likely there was more than one domestication event, although Smithsonian concedes a scientific disagreement on that point. The multiple-domestication theory states that humans domesticated early wolf descendants in both the East and the West independently around the same time. This created a fork in the DNA of dogs, which were continuously bred both with each other and with wolves in both the East and the West, creating a menagerie of different dog species.

12,000 years ago: Agricultural Revolution changes man and dog

Around 10,000 B.C., millions of years of behavior natural to the genus Homo came to a screeching halt when human beings shifted from the lifestyle of nomadic hunters and foragers to that of stationary farmers. Their dogs settled down with them and, according to the Gettysburgian, the most dramatic societal change in the history of human beings forever altered the genes of both man and dog.

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10,000 years ago: Dogs get jobs
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10,000 years ago: Dogs get jobs

Since their earliest domestication, dogs helped humans track prey and avoid being preyed upon. The Agricultural Revolution, however, signaled the arrival of specialist dogs that did more than follow scents and make noise when danger was near. Upon settling down on farms, humans bred dogs with characteristics favorable to specific agricultural tasks like herding livestock—instead of eating them like their wolf ancestors; protecting chickens, pigs, and other farm animals; finding lost animals; and terrorizing and killing pests like mice and rats.

[Pictured: How to treat diseases and injuries of the dogs from "The Book of the Hunt" by Gaston III Phoebus.]

8,000 years ago: The basenji arrives

Around 8,000 years ago, the original dog that had diverged from a common ancestor with the gray wolf had gone extinct. Around that time, the basenji emerged as the first and oldest modern dog species. Smart and independent, the so-called African "barkless dog" is still recognized by the American Kennel Club today.

6,000 years ago: Dogs go urban

The Agricultural Revolution gave humans an unprecedented level of food security that, for the first time in history, made large, permanent settlements possible. The first large-scale civilizations arrived with the Sumerians in Mesopotamia around 4000 B.C. and by this point, wherever people went, dogs went, too. Man's best friend has been a common sight in cities for as long as cities have existed.

5,300 years ago: Dogs get leashes and collars

The early Mesopotamians urbanized dogs, and city dogs need leashes and collars. According to the Ancient History Encyclopedia, dogs are depicted wearing leashes and collars in antiquity artwork from Rome to China. It was the Sumerians who invented the world's most familiar dog accessories around 3300 B.C.

5,000 years ago: Eastern dogs win the genetic war

At some point, according to the Atlantic, the dogs in the East—and their human masters—began winning the biological battle of genetics. Today, just 10 percent of the planet's dogs trace their DNA to that of Ancient Western dogs, which have since become extinct.

4,000 years ago: Ancient dogs enter human literature
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4,000 years ago: Ancient dogs enter human literature

Long before Clifford the Big Red Dog, there was The Show Dog and Why the Dog is Subservient to Man. These two ancient tablet-based texts were written around 2000 B.C., long before Aesop's Fables made dogs a common subject of literature. Once again, early dog lovers had the Sumerians to thank.

4,000 years ago: Dogs as deities
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4,000 years ago: Dogs as deities

The ancient Mesopotamians were the first human societies known to deify dogs and include versions of dogs among their gods and their religious practices. Later, cultures across the world and the ages would do the same thing. Dogs, dog-human hybrids, and dog-related imagery played a role in mythology in Babylonian, Egyptian, Greek, Aztec, Norse, and Hindu cultures.

[Pictured: Anubis warming the heart of the deceased, northern wall of the burial chamber, Tomb of Sennedjem, Egypt.]

A.D. 43: Dogs take to the battlefield

In A.D. 43, Rome, whose armies had already been using dogs as military animals, invaded Britain. Although the Romans won the battle, the tribes of Britannia terrorized and inspired the Romans with their far more ferocious and battle-ready canines. The Romans soon began placing a much heavier focus on integrating dogs into their strategies of military conquest.

First century: The military dog market emerges
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First century: The military dog market emerges

Once the Romans placed a premium on warrior dogs, breeders and traders across Europe began mating, mixing, and selling breeds specifically bred and trained for use by the Roman military in sprawling European war dog markets. Many wound up on the battlefield, fighting alongside their masters in the Roman legions. Many others, however, were doomed to compete in the gruesome spectacles that were Roman gladiator shows, where dogs were pitted against other animals and even humans in mortal combat.

[Pictured: Detail from a mosaic floor in the House of Paquius Proculus or of Cuspius Pansa, Pompeii.]

Seventh century: St. Hubert breeds his hounds

In the seventh century, a French monk named Hubert, later to be sainted, began breeding what would come to be known as St. Hubert's hounds. Large, robust dogs, these early scent hounds were bred and trained to recognize and pursue specific, individual scents over great distances. They are believed to be the original ancestor of all modern bloodhounds, and St. Hubert is known as the patron saint of hunters.

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12th century: Baiting emerges as a European pastime
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12th century: Baiting emerges as a European pastime

By the 1100s, a blood sport that would be considered cruel and gruesome even by the standards of the ancient Romans had gone mainstream in England: baiting. Large crowds gathered in arenas to watch packs of hungry, provoked dogs torment, terrorize, and tear apart larger animals—most notably bears and bulls—that were chained and defenseless. One of the darker chapters in the long, disturbing history of blood sport entertainment, the era would have a dramatic impact on the future of dog welfare.

1493: European dogs travel to the New World

On Christopher Columbus' second voyage to the Americas, he and his crew brought 20 greyhounds and mastiffs—the first European dogs ever to set foot in the New World. They brought dogs for two reasons: to use them as guinea pigs for testing unfamiliar food and to intimidate and terrorize natives that lived on islands like Hispaniola. Columbus and his men embarked on a campaign of subjugation, mass murder, rape, and enslavement of New World natives, and they used dogs to track escapees and to maul to death captured rebels as an example to the others or simply for entertainment.

16th century: Hounds become human trackers

Since the time of Hubert, hounds—with their powerful noses, scent-trapping folds of skin, and solemn, bloodshot eyes—had been used to track boars, deer, and other common human prey. In the 16th century, however, humans began using modern bloodhounds to relentlessly track other humans, including escaped prisoners, fleeing warriors, and most notably, runaway slaves. It's hard to imagine that any sound was more terrifying to an escaped enslaved person than the baying of approaching bloodhounds, which were used by cruel masters to track, torment, and terrorize captive laborers throughout the history of trans-Atlantic slavery.

1750s: The guide dog movement is born
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1750s: The guide dog movement is born

In the 1750s, professionals working at a Paris hospital for the blind began training dogs to aid and guide visually impaired humans. In 1819, an Austrian named Johann Wilhelm Klein, who started the Institute for the Training of the Blind in Vienna, published the first guide dog training manual, complete with instructions on incorporating a special harness and a pole, a technique that is still in use today.

Late 18th century: Modern dog sledding is born

It's believed that Indigenous Northern Canadian Inuit people incorporated load-hauling dogs into their lives and work as early as 1980 B.C., but Russian explorers in Alaska are credited with bringing dog sledding into the modern era in the late 1700s. The Russians trained a lead dog, or alpha dog, to respond to specific commands and to keep the subordinate dogs in the pack in line and working hard. Dogs would become to people in frozen, snowy climates what camels were to Arab merchants in the Middle East—the backbone of commerce, trade, travel, and communication over distance.

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1835: Modern dogfighting emerges

In 1835, the British Parliament outlawed the gruesome entertainment sport of baiting, which involved ravenous dogs being turned on chained bears and bulls. The move came after a shift in public sentiment regarding the brutality of the spectacle and a dwindling population of bears. While good for the larger animals, the same can't be said for dogs—revelers then simply began pitting dogs against other dogs for sport and wagering on the outcome, a practice that still continues underground today.

1850s: The pit bull earns its reputation—involuntarily

Dogfighting quickly gained popularity around the world, including in the pre-Civil War United States. During that era, dogs were bred for characteristics specific to dogfighting in an effort to develop the fiercest, most aggressive, and most durable breed for the brutal spectacle of dog-on-dog death matches. What emerged was the American pit bull terrier.

1866: The ASPCA is formed
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1866: The ASPCA is formed

In 1866, an American diplomat named Henry Bergh resigned his government post and dedicated his life to his passion of protecting vulnerable animals, which were worked in every field of agriculture and industry in often deplorable conditions without any protections or legal standing. Bergh founded the American Society for the Prevention of Cruelty to Animals (ASPCA), which worked to raise awareness and advocate for animal abuse legislation. Its original mission was to protect horses, but it would soon evolve to include all animals in its mission, few more notably than the venerable dog.

[Pictured: Street-cab horses drinking water provided by the ASPCA in New York City, 1911.]

1877: First Westminster Kennel Club Dog Show

The Westminster Kennel Club Dog Show, held every year at New York City's Madison Square Garden (MSG), is known as America's dog show around the world and traces its roots to 1877. That year, the Westminster Kennel Club staged a show designed to find the best of purebred dogs in an all-breed competition at Gilmore's Garden, the previous incarnation of MSG. Held annually with no exceptions, including through World War II and the Great Depression, only the Kentucky Derby can boast a longer continuous run—but just by two years.

1878: The Original 9
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1878: The Original 9

In 1878, Westminster and the other big 19th-century kennel clubs officially recognized nine "charter breeds" of dogs, most of which were among the in-demand hunting breeds of the day. They were the Gordon setter, English setter, Irish setter, Irish water spaniel, Sussex spaniel, cocker spaniel, clumber spaniel, Chesapeake Bay retriever, and the pointer. The original nine breeds would expand continuously throughout the decades under the stewardship of what is considered the most important pedigree registry: the American Kennel Club.

1884: The American Kennel Club is formed
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1884: The American Kennel Club is formed

In 1884, 12 officials from dog clubs across America held the first official meeting of the American Kennel Club (AKC). The AKC was formed to unify and regulate America's dog clubs, serve as a national registry for officially recognized breeds, and to sanction major dog shows, including Westminster. It remains the country's preeminent organization dedicated to dogs.

[Pictured: E.L. Pulsifer with Champion Maurice II, (French bulldog) in 1905.]

1899: Dogs join the force
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1899: Dogs join the force

As early as 1888, police in London used hounds to try to search for Jack the Ripper, but they weren't trained any differently than human-tracking scent hounds had been for centuries. About a decade later in 1899, however, police officials in Ghent, Belgium, began formally training canines for work alongside law enforcement officers. It was the genesis of the modern K-9 cop.

1903: London publishes 'The Call of the Wild'

In 1903, author Jack London wrote his masterpiece and one of the great classic American novels. The Call of the Wild tells the tale of Buck, a large Saint Bernard-Scotch collie mix that was kidnapped from his cozy California home and sold to Canadian prospectors during the Klondike Gold Rush. The book, which honors the spirit of rugged perseverance and man's intimate relationship with dogs, captured America's imagination and gave birth to a new generation of dog lovers.

1904: An ancient breed receives modern validation
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1904: An ancient breed receives modern validation

No small dog has a bigger personality than the feisty and beloved Chihuahua. The breed that has evolved into the ultimate purse dog is one of the oldest canines in the Americas, with roots dating back to the pre-Columbian era. It remains a national symbol of Mexico and a fixture in the designer pocketbooks of socialites everywhere.

1908: The German shepherd earns its place
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1908: The German shepherd earns its place

Big, loyal, capable, confident, and supremely intelligent, the German shepherd was first recognized by the AKC in 1908. The #2 most popular dog behind only the Labrador retriever, the German shepherd is widely considered to be the most trainable, most reliable, and most competent all-purpose dog in the world by military agencies, law enforcement organizations, and civilian dog lovers alike.

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1917: America’s favorite dog gets its due
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1917: America's favorite dog gets its due

In 1917, the AKC recognized the Labrador retriever as a distinct breed. It would go on to become one of the most popular and beloved dogs in American history. Amazingly, it has been the most popular breed in the country for nearly three decades straight.

1930s: Dogs become mountain rescuers

In the 1800s, European monks traveling through the Alps often brought Saint Bernards to lead the way—the big, sturdy dogs were known to sniff out and locate monks that fell down or became buried in snow. In the 1930s, the Swiss began training dogs—originally Saint Bernards with their iconic neck-worn rescue barrels—specifically to locate and rescue people buried in avalanches. Saint Bernards were soon mostly replaced with different kinds of shepherds and retrievers, and avalanche rescue dogs still play critical roles on mountain retreats today.

1939: Toto leaves Kansas

Aug. 25, 1939, was a defining, before-and-after moment in Hollywood history—that day, "The Wizard of Oz" hit theaters and raised the cinematic bar forever. Upon waking up in the magical land of Oz, Judy Garland's Dorothy uttered the phrase, "Toto, I have a feeling we're not in Kansas anymore." It stands as one of the greatest quotes ever uttered on the big screen and the world's most famous Cairn terrier remains one of the most beloved movie dogs in history.

1943: A dog is decorated
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1943: A dog is decorated

At the height of World War II, a German shepherd mix named Chips was awarded a Purple Heart, a Distinguished Service Cross, and a Silver Star for his role in helping American troops take an enemy machine gun position and capture 10 Italian troops—he also saved his handler's life. The gesture did not sit well with some human veterans, and Chips' medals were revoked. Although Chips later got his medals back, the War Department ruled that no other military dogs would ever receive official military medals.

[Pictured: Chips getting a donut from a G.I. in 1944.]

1952: Nixon makes the Checkers speech
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1952: Nixon makes the Checkers speech

On Sept. 23, 1952, a shrewd politician and California senator named Richard Nixon was the Republican candidate for vice president of the United States when he was accused of illegally using political donations for personal expenses. In a speech seen by what was then television's largest-ever audience, he attacked his opponents and denied the charges. In a clever effort to humanize and endear himself to voters, he insisted that no matter the consequences, he would be keeping one item purchased with the funds—Checkers, his beloved cocker spaniel.

[Pictured: Sen. Richard Nixon with family and dog Checkers in September 1952.]

1954: Lassie begins its 20-year run

Few dogs have ever embodied the "man's best friend" concept more than Lassie, the namesake character of one of television's earliest defining shows. The trusty pet of the fictional Martin family, the iconic rough collie alerted her human companions to danger, saved lives, and ran to get help. Just as in real life, the people closest to her had an uncanny knack of understanding exactly what Lassie was trying to tell them.

1957: Dogs beat humans into outer space
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1957: Dogs beat humans into outer space

On Nov. 3, 1957, the United States was still reeling from the Soviet launch of the Sputnik satellite one month earlier. Eager to capitalize on Sputnik's propaganda value, the Soviets launched Sputnik 2, a much bigger craft with room for a very special passenger. That day, a dog named Laika became the first animal to orbit Earth, although the Russians made no effort to recover Laika, who probably died while in orbit.

1960s: Dogs double as therapists
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1960s: Dogs double as therapists

The service dog concept had been around for centuries, but in the 1960s, researchers began experimenting with dogs serving people not as guides or helpers, but as a form of living therapy. What they learned was that the elderly, the mentally disabled, people suffering from depression, trauma survivors, and many other populations dealing with mental anguish could experience relief just by being in the company of well-trained canines. The era of the therapy dog had arrived.

1963: The world meets Clifford
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1963: The world meets Clifford

In 1963, Scholastic published a children's book by author Norman Bridwell titled Clifford the Big Red Dog. Chronicling the unusual life of an enormous red Labrador retriever, the book became an instant classic, spawned a series, and launched a merchandising powerhouse while putting Scholastic in the big leagues of the publishing industry. To this day, Clifford is still the official Scholastic mascot.

[Pictured: Author Norman Bridwell celebrates Clifford The Big Red Dog 50th Anniversary Celebration at the Scholastic Flagship Store on Sept. 24, 2012, in New York City.]

1969: The spaying and neutering era begins
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1969: The spaying and neutering era begins

In 1969, America's first low-cost spaying and neutering clinic for animals opened in Los Angeles. Sterilization was originally offered as a convenience for pet owners, but the procedure would soon become a paramount issue of the animal welfare movement. As the population of unwanted, neglected, abused, and homeless dogs grew larger every year, activists worked to change the public mindset on spaying and neutering.

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1972: The ASPCA makes sterilization mandatory
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1972: The ASPCA makes sterilization mandatory

Just three years later in 1972, the ASPCA required sterilization for all animals adopted from its massive network of shelters. Shelter intake rates began to drop almost immediately and today, euthanasia rates for dogs and cats have dropped by 90 percent compared to 50 years ago.

1973: The world’s most famous dog race begins
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1973: The world's most famous dog race begins

In 1973, mushers competed in the inaugural installment of what's known as "The Last Great Race on Earth," the grueling Iditarod Trail Sled Dog Race, which runs through nearly 1,000 miles of Alaskan wilderness from Anchorage to Nome. The competition is an homage to the tens of thousands of prospectors—along with their countless trusty sled-pulling dogs—who flooded Northern Canada and Alaska in the late 19th century during the Klondike and Nome gold rushes.

1974: Benji puts mutts on the map

The same year "Lassie" ended its two-decade run on TV, a different dog barked his way into America's heart on the big screen. Just like Lassie, Benji had a knack for averting trouble and being in the right place at the right time—but unlike the famous rough collie, the namesake character of the long-running "Benji" film franchise was no pedigree. The beloved mixed-breed would become America's favorite mutt.

1981: King publishes 'Cujo'

Some fictional dogs are cute and fuzzy—Cujo is not one of them. Murphy's Law rules the day in the Stephen King tale of a 200-pound Saint Bernard with rabies and a murderous fixation on a mother and her child who are trapped inside a broken-down Ford Pinto. To this day, the name "Cujo" is synonymous with dogs that are not to be trifled with and are dangerous.

1989: The Labradoodle arrives
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1989: The Labradoodle arrives

In 1989, guide dog breeder Wally Conron attempted to create a dander-free, non-shedding guide dog for blind allergy sufferers. The result was an utterly adorable service animal with the work abilities of a Labrador retriever and the clean coat of a poodle. The Labradoodle, one of the most famous and controversial hybrid species in modern history, was born—or created.

1990s: The no-kill movement emerges
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1990s: The no-kill movement emerges

By the last decade of the 20th century, the ASPCA's mandatory spay/neuter program was so successful in reducing shelter intake that something became possible that would have been unimaginable just a few decades earlier. The organization launched what came to be known as the no-kill movement, a policy that compelled shelters to reevaluate the need to euthanize healthy animals.

2001: 9/11 dogs offer hope in times of terror
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2001: 9/11 dogs offer hope in times of terror

On Sept. 11, 2001, there was little reason for hope or happiness, but an army of canines now known simply as the "9/11 dogs" offered a glimmer of both on that dark day and the ensuing weeks and months. Some searched the rubble for survivors, others for bombs, others for bodies—some were there only to provide comfort and companionship to distressed rescuers and first responders. They had names like Bretagne, Riley, Guinness, Coby, Appollo, Thunder, and Sage—before 9/11 most Americans had never heard of disaster search dogs.

[Pictured: Mike Scott from the California Task Force-8 and his dog, Billy, search through rubble for victims of the September 11 terrorist attack at the World Trade Center, Sept. 21, 2001, New York City.]

2000s: Dogs find internet fame
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2000s: Dogs find internet fame

The arrival of social media and sites such as YouTube gave rise to a new kind of superstar—dogs that were internet famous. From the odd to the adorable, pooches like Tuna, Boo, Digby Van Winkle, and Lentil went viral the world over—and sometimes made very rich humans out of their owners.

[Pictured: Jiff the Pomeranian attends Nickelodeon's 2018 Kids' Choice Awards at The Forum in Inglewood, California, March 2018.]

2010s: Dogs sniff out disease
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2010s: Dogs sniff out disease

A series of scientific studies in the 2010s revealed that dogs—and their incredibly sensitive noses—might hold the key to a 21st-century medical revolution. Some breeds of dogs, it turns out, are incredibly adept at physically smelling the presence of infections, diseases, and other ailments, including malaria and cancer, on patients and even on the clothing of the afflicted.

[Pictured: Freya correctly detects a sample of malaria from a row of sample pots at the Medical Detection Dogs charity headquarters on March 27, 2020, in Milton Keynes, England.]

2020: The AKC greets two new arrivals
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2020: The AKC greets two new arrivals

The AKC currently recognizes 195 distinct dog breeds. The most recent inductees are the Barbet and the Dogo Argentino, both inducted in 2020. The Azawakh joined the club in 2019 and in 2018, the AKC recognized the Nederlandse Kooikerhondje and the Grand Basset Griffon Vendéen.

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