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The Story Behind Man's Best Friend

There are around 400 million dogs in the world, the majority of which are pets. While the animals know a surprisingly large amount about their human companions, there’s plenty we still don’t know about them. In celebration of National Dog Week, here’s all kinds of information that you probably never knew about your best friend.

A Brief History of Inter-Species Love

While the exact time that humans and dogs started to socialize together is unknown, most researchers agree that the pairing occurred at least 15,000 years ago. There is evidence dogs were domesticated by 12,000 BC, as archaeologists have discovered an Israeli grave site from this time period where an old man had been buried with a puppy.

While early researchers argued whether dogs were most closely related to coyotes, dingoes or wolves, DNA evidence has proven conclusively that our four-legged friends are most closely related to gray wolves. The means that the animals became domesticated is contested, but one common theory says that wolves started to scavenge around human campsites where they could get meals with minimal effort and that wolves that were less frightened by humans soon saw an advantage in aligning themselves with paleolithic man.

Image courtesy of Sometimesong's Flickr stream.

In the beginning, both species would gain significant benefits from one another.

Dogs would be safer, have a more reliable food source and benefit from humans' ability to see predators and prey from a long distance. Humans would benefit as dogs increased sanitation by cleaning waste and food scraps; dogs also would have used their excellent hearing to warn humans of approaching animals. On the hunt, dogs would be able to use their strong sense of smell to track prey, as man used his tools to bring down large animals with less effort. Both species would also benefit from the increased body warmth during cold nights. It is very likely that humans not only shaped the future of dogs, but that dogs changed our evolutionary course as well.

As the years wore on, dogs continued to play an important role in human history. Many people believe that humans could not have successfully traveled across the Bering Straight without the help of sled dogs. After crossing, dogs continued to be important to Native Americans and served as their only domesticated animal until the Spanish introduced the horse. Many cultures even continued to use dogs as pack animals long after horses were introduced to the continent.

Selective breeding allowed certain dogs to excel at certain tasks, such as herding, ratting, hunting or carrying weight. The idea of pets solely for the sake of companionship wasn’t such a major part of the average person’s life until the suburbanization of Western culture after World War II. While dog training existed long before this, the idea of breaking the animals of their natural digging, barking and jumping instincts only really took off after this point and it seems we may be on the cusp of a new evolutionary mark for dogs as they are increasingly bred for companionship skills rather than working skills.

Image courtesy of nyominx's Flickr stream.

Cross-Species Benefits

Most people can immediately see the benefit modern dogs get from humans (food, shelter, water and affection), but the benefits our pets bring to us is equally impressive. Modern service dogs can be trained to not only help those with external physical disabilities, but also to help warn epileptics and diabetics about upcoming attacks while they still have time to do something about it. The animals can also be useful in treating anxiety, depression and Post Traumatic Stress Disorder.

Dogs can even be used to detect oncoming conditions such as cancer. When a control group of dogs were trained to smell out lung or breast cancer in the breath of test subjects, their accuracy stayed between 88 and 97 percent. It sure is a whole lot less invasive than a biopsy.

People who own pets, whether dogs or cats, have been shown to be healthier and happier than those who do not own an animal. In fact, one study showed pet owners had a major reduction in minor health problems during their first month of ownership and dog owners continued to show these improvements through the duration of the study.

Image courtesy of Martin Kuo's Flickr stream.

What’s Breed Got To Do With It?

Dogs have more variations in size, appearance and behavior than any other animal on earth because they have been targets of artificial selection through human interference, rather than natural selection. Scientists have even recognized 155 distinct genetic locations that account for all of these differences.

Dog sizes vary from the world’s smallest dog, a 2.5 inch tall Yorkshire Terrier that weighed 4 ounces, to the world’s tallest dog, a Great Dane that stands at 43 inches (that's him above), to the 343 pound English Mastif that was named the world’s largest dog. Similarly, dog lifespans, which are around 11 years on average, vary greatly by breed. In fact, the Dogue de Bordeaux has a notably short lifespan that averages just over five years. Many other breeds, including Toy Poodles, Japanese Spitz and others have an average lifespan of fourteen and a half years. Strikingly, the world’s oldest dog, an Australian Cattle Dog named Bluey, lived to be almost 30.

Breeding can also affect the level of energy and muscle a particular dog has. Some of the best athletic dogs are the Siberian Huskies used in the Iditarod sled race. Scientists fount that these animals burned 11,000 calories the day, which is eight times the proportional calories burned by a Tour de France cyclist. They also take in three times the oxygen of human athletes.

Another famed animal athlete is the Greyhound, which is one of the fastest accelerating animals in the world, second only to the cheetah. Greyhounds have an incredible heart, the same size as a human, but that beats at twice the speed of a human when exercising.

Startling K-9 Psychology


Image courtesy of PKMousie's Flickr stream.

While people like to think we have more in common with our primate ancestors than any other animal, when it comes to communication and social dynamics, we actually have more in common with dogs. Researchers have said that while dogs are only as smart as two-year old humans, they have the social skills of teenagers. In fact, dogs are the only animals that understand pointing. They understand human languages better than other primates and the average dog can be taught as many as 165 words, more than an ape can learn. Particularly smart dogs have even been taught over 300 words.

Dogs understand deception, which chimps cannot grasp as clearly. Researchers tested this by placing two covered buckets, one with a treat and one without, in front of the dog. Half of the dogs would be directed to the wrong bucket by a person in the room, while the others would be given correct signals. While all of the dogs would start out listening to the human, those that were being lied to soon started going to the opposite bucket.

Dogs also know how to deceive humans without getting caught. To test this, dogs were left in a room with two containers with bells, one of which was muted and one of which was not. Researchers observed that when the animals were being watched, they would go to either of the containers, but when the observer looked away, the animals would always go for the quiet container.

If you’ve ever had a dog get in trouble, you probably know that dogs can show guilt, but it is worth noting that researcher Frans de Waal has proven that their expression of guilt applies whenever the dog thinks he or she will get in trouble, regardless of whether or not he or she actually did something bad. So if you have more than one dog, you might not want to blame the one who looks guilty automatically; he or she might just be worried they’ll get in trouble for the actions of their co-habitant.

Image courtesy of srte's Flickr stream.

I learned my dog is the jealous type when I came home and greeted my roommate’s dog before him. He immediately tried to fight her. Apparently, I was on to something here, because Vienna researchers studied whether dogs can get jealous of one another a little while ago by rewarding one dog with a treat for doing a trick and then asking the other to do the trick without a reward. The unrewarded dog soon got annoyed and stopped performing the trick, which did not happen when the same animal went unrewarded without another dog around. Up until that time, primates were the only animals known to show signs of jealousy.

Do you have a dog? Share your favorite stories about his or her behavior in the comments.

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History
Scientists Reveal Long-Hidden Text in Alexander Hamilton Letter
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iStock

Age, deterioration, and water damage are just a few of the reasons historians can be short on information that was once readily available on paper. Sometimes, it’s simply a case of missing pages. Other times, researchers can see “lost” text right under their noses.

One example: a letter written by Alexander Hamilton to his future wife, Elizabeth Schuyler, on September 6, 1780. On the surface, it looked very much like a rant about a Revolutionary War skirmish in Camden, South Carolina. But Hamilton scholars were excited by the 14 lines of writing in the first paragraph that had been crossed out. If they could be read, they might reveal some new dimension to one of the better-known Founding Fathers.

Using the practice of multispectral imaging—sometimes called hyperspectral imaging—conservationists at the Library of Congress were recently able to shine a new light on what someone had attempted to scrub out. In multispectral imaging, different wavelengths of light are “bounced” off the paper to reveal (or hide) different ink pigments. By examining a document through these different wavelengths, investigators can tune in to faded or obscured handwriting and make it visible to the naked eye.

A hyperspectral image of Alexander Hamilton's handwriting
Hyperspectral imaging of Hamilton's handwriting, from being obscured (top) to isolated and revealed (bottom).
Library of Congress

The text revealed a more emotional and romantic side to Hamilton, who had used the lines to woo Elizabeth. Technicians uncovered most of what he had written, with words in brackets still obscured and inferred:

Do you know my sensations when I see the
sweet characters from your hand? Yes you do,
by comparing [them] with your [own]
for my Betsey [loves] me and is [acquainted]
with all the joys of fondness. [Would] you
[exchange] them my dear for any other worthy
blessings? Is there any thing you would put
in competition[,] with one glowing [kiss] of
[unreadable], anticipate the delights we [unreadable]
in the unrestrained intercourses of wedded love,
and bet your heart joins mine in [fervent]
[wishes] to heaven that [all obstacles] and [interruptions]
May [be] speedily [removed].

Hamilton and Elizabeth Schuyler married on December 14, 1780. So why did Hamilton try and hide such romantic words during or after their courtship? He probably didn’t. Historians believe that his son, John Church Hamilton, crossed them out before publishing the letter as a part of a book of his father’s correspondence. He may have considered the passage a little too sexy for mass consumption.

[h/t Library of Congress]

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History
7 of History’s Most Unusual Riots
Scott Barbour/Getty Images
Scott Barbour/Getty Images

Some sociologists theorize that most rioters only join a crowd because the crowd is big enough to justify joining. But there’s always that one person who sparks the violence, and sometimes the reason for doing so can seem pretty baffling. Maybe a work of art scandalizes its audience, like the famous premiere of Igor Stravinsky’s The Rite of Spring. Or maybe it’s simply a notable act of disrespect, like history’s first recorded mooning (in Jerusalem in the first century CE). From balloonists to brown dogs to daylight saving time, here are seven weird reasons things just got out of hand.

1. THE MELBOURNE DART RIOT

The Darts Invitational Challenge, an international tournament held in Melbourne, attracted international gawking in January 2015 during the finals match between Michael "Mighty Mike" van Gerwen and Simon "The Wizard" Whitlock. The dart players weren’t making a scene, though: Rather, hundreds of spectators, many of them drunk and in costume, began throwing plastic chairs as they watched (pictured above). The reasons for the fight remain unclear; footage and photos show police trying to control adults dressed as Oompa-Loompas, numerous superheroes, and, in one instance, in a ghillie suit (heavy camouflage meant to resemble foliage).

2. THE LEICESTER BALLOON RIOT

In 1864, balloonists were the great daredevils of their time, and a major draw for eager audiences. That summer, Henry Coxwell, a famous professional aeronaut, was set to make an appearance for 50,000 paying ticketholders in Leicester, England. Unfortunately, a rumor spread that he hadn’t brought his biggest and best balloon to the event. After heckling from the crowd, Coxwell deflated his balloon, and attendees rushed it, ripping it to shreds, setting it on fire, and threatening to visit the same fate on Coxwell. Rioters even paraded the remains of the balloon through the streets of town, which briefly brought residents a new nickname: Balloonatics.

3. THE TORONTO CLOWN AND FIREFIGHTER RIOT

Toronto was still a pretty rough place in the 1850s, but not so rough that the circus wouldn’t come to town. As it turns out, circus entertainers were also a tough lot back then, so when a group of off-duty clowns spent an evening at a brothel popular with the city’s firefighters on July 12, 1855, tensions came to a head. Accounts differ as to who started the fight, but after one firefighter knocked the hat off a clown things escalated into a full-on rabble intent on chasing the circus out of town. Only the mayor calling in the militia put an end to the uproar, an incident Torontonians credit with kicking off much-needed local police reforms.

4. THE BELGIAN NIGHT AT THE OPERA RIOT

A painting by Charles Soubre of the Belgian Revolution
Charles Soubre, Wikimedia Commons // Public Domain

Not many nations can claim their independence started with an aria, but for 19th-century Belgians sick of living under Dutch rule, an opera was just the right fuse for a revolution. To honor the birthday of King William I of the Netherlands, a theater in Brussels put on La Muette de Portici, about an uprising in Naples against Spanish rule. One song, "Amour Sacre de la Patrie" ("Sacred Love of the Fatherland"), aroused nationalistic passions so much that after the opera ended, the crowd began destroying factories and occupying government buildings. That was August 25, 1830; Belgium declared independence on October 4.

5. THE NEW YORK DOCTORS' RIOT

Hamilton fans, take note: Everyone’s favorite Founding Father once tried to quiet a mob bent on burning corpses. For centuries, anatomists and medical students relied on gruesome means to learn about the human body. Cadavers for dissection class often came from grave robbers, since the corpses of executed criminals were the only legal source—and they were in limited supply. In New York in 1788, rumors abounded that medical students were digging up paupers’ graves and black cemeteries. When one mob came after the doctors responsible, Alexander Hamilton tried, and failed, to restore the peace. The crowd swelled to about 5000 before militiamen intervened, leading to up to about 20 deaths.

6. THE BROWN DOG RIOTS

Photo of an anti-vivisection demonstration in Trafalgar Square, London, to protest the removal from Battersea Park of the Brown Dog statue
The Anti-Vivisection Review, Wikimedia Commons // Public Domain

Riots against the dissection of dead human bodies were not rare in the United States at one time. But on December 10, 1907, a thousand Britons marched in support of vivisection, or surgery on live animals. At the center of the controversy was a small terrier allegedly vivisected without anesthetic in 1903 during a class at London’s University College. Animal rights activists erected a statue to the dog in 1906, which enraged area medical students, and protesters tried to destroy the statue using crowbars and hammers. For the 1907 march, 400 mounted police were deployed to contain marchers. The statue became such a flashpoint (and an expense to local authorities) that in 1910, it was removed and melted down.

7. THE EEL-PULLING RIOT

Palingtrekken (eel-pulling) was once a popular contest in Amsterdam, in which a writhing eel was suspended over a canal and hopefuls on boats would leap to snatch it as they passed beneath (usually landing in the water instead). However, “eel-pulling” was also illegal—the government deemed it a “cruel popular entertainment”—and in July 1886, police intervened at a particularly large gathering in the city’s Jordaan district. Civilians threw stones and bricks at police, and when some nearby socialist protestors joined them, a riot broke out that lasted for several days. The army finally intervened and opened fire on the protestors. All in all, 26 people died and 136 were wounded, but somehow, the eel itself at the center of the riots was allegedly saved and auctioned off in 1913.

A version of this story originally ran in 2015.

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