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.

Sergeant Marshall/Department of Defense, NARA // Public Domain
Would You Be Able to Pass a World War I Military Literacy Test?
Sergeant Marshall/Department of Defense, NARA // Public Domain
Sergeant Marshall/Department of Defense, NARA // Public Domain

Though reading and writing might not come to mind as the first requirement for trench warfare, during the early 20th century, the U.S. Army became increasingly concerned with whether or not its soldiers were literate. Thousands of World War I soldiers couldn't read printed directions on basic military tasks. The Army didn't implement its first major literacy program until the 1940s, but literacy tests were included in a battery of psychological evaluations World War I recruits went through to determine their mental fitness and intelligence, as the blog Futility Closet recently highlighted.

These unconventional literacy tests largely took the form of a yes or no questions with obvious answers, according to the 1921 report from the U.S. Surgeon General, Psychological Examining in the United States Army. Edited by pioneering intelligence-testing psychologist Robert Yerkes, who developed the military's first psychology exams for new recruits (and was also famous for his support for eugenics), the volume is a lengthy compilation of all of the methods the U.S. Army used to test the intelligence of its future soldiers. Many of these tests are now considered racist and culturally biased—some of the "intelligence" testing questions required recruits to know things like what products Velvet Joe (a figure used in tobacco campaigns) advertised—but some of the literacy questions, in particular, simply come off as weird in the modern era. Some are downright existential, in fact, while others—"Is a guitar a disease?"—come off as almost poetic.

A long questionnaire to test literacy, including questions like 'Is coal white?'
Psychological Examining in the United States Army, Google Books // Public Domain

One test, the Devens Literarcy Test, asked recruits questions like "Is genuine happiness a priceless treasure?" and "Does success tend to bring pleasure?" Another section of the test asked "Do boys like to play?" and "Do clerks enjoy a vacation?"

Other questions seem like they're up for debate, like "Are painters ever artless individuals?" and "Is extremely athletic exercise surely necessary?" Surely the answers to questions like "Should criminals forfeit liberty?" and "Is misuse of money an evil?" depend on the opinions of the reader. The answer to "Do imbeciles usually hold responsible offices?" might be different depending on how the person feels about their Congressional representative, and could surely be the spark for an hour-long argument at most dinner parties.

Still others are tests of cultural knowledge, not reading skill—a major modern criticism of Yerkes's work. Despite being arguably a pretty literate person, I certainly don't know the answer to the question "Do voluntary enlistments increase the army?" A question like "Are 'diminutive' and 'Lilliputian' nearly identical?" isn't exactly a test of literacy, but a test of whether or not you've read Gulliver's Travels, which doesn't exactly seem like a necessity for military success.

Luckily, some of the questions are pretty obvious, like "Is coal white?" That one I can answer. The full list of questions used in the various versions of the Devens test is below for you to test your own Army-level literacy.

  • Do dogs bark?
  • Is coal white?
  • Can you see?
  • Do men eat stones?
  • Do boys like to play?
  • Can a bed run?
  • Do books have hands?
  • Is ice hot?
  • Do winds blow?
  • Have all girls the same name?
  • Is warm clothing good for winter?
  • Is this page of paper white?
  • Are railroad tickets free?
  • Is every young woman a teacher?
  • Is it always perfect weather?
  • Is the heart within the body?
  • Do clerks enjoy a vacation?
  • Is the President a public official?
  • Would you enjoy losing a fortune?
  • Does an auto sometimes need repair?
  • Is it important to remember commands?
  • Are avenues usually paved with oxygen?
  • Do we desire serious trouble?
  • Is practical judgment valuable?
  • Ought a man's career to be ruined by accidents?
  • Do you cordially recommend forgery?
  • Does an emergency require immediate decision?
  • Should honesty bring misfortune to its possessor?
  • Are gradual improvements worth while?
  • Is a punctual person continually tardy?
  • Are instantaneous effects invariably rapid?
  • Should preliminary disappointment discourage you?
  • Is hearsay testimony trustworthy evidence?
  • Is wisdom characteristic of the best authorities?
  • Is extremely athletic exercise surely necessary?
  • Is incessant discussion usually boresome?
  • Are algebraic symbols ever found in manuals?
  • Are tentative regulations ever advantageous?
  • Are "diminutive" and "Lilliputian" nearly identical?
  • Is an infinitesimal titanic bulk possible?
  • Do all connubial unions eventuate felicitously?
  • Is a "gelatinous exaltation" ridiculous?
  • Are "sedate" and "hilarious" similar in meaning?
  • Is avarice sometimes exhibited by cameos?
  • Can a dog run?
  • Is water dry?
  • Can you read?
  • Do stones talk?
  • Do books eat?
  • Do cats go to school?
  • Are six more than two?
  • Is John a girl's name?
  • Are there letters in a word?
  • Is your nose on your face?
  • Can you carry water in a sieve?
  • Do soldiers wear uniforms?
  • Does it rain every morning?
  • Are newspapers made of iron?
  • Are "forward" and "backward" directions?
  • Do many people attend motion-picture theatres?
  • Do handkerchiefs frequently injure human beings?
  • Do magazines contain advertisements?
  • Are political questions often the subject of debates?
  • Are empires inclosed in envelopes?
  • Are members of the family usually regarded as guests?
  • Is genuine happiness a priceless treasure?
  • Do imbeciles usually hold responsible offices?
  • May chimneys be snipped off with scissors?
  • Is moderation a desirable virtue?
  • Are apish manners desired by a hostess?
  • Do conscientious brunettes exist?
  • Do serpents make oblong echoes?
  • Do voluntary enlistments increase the army?
  • Is hypocrisy approved by honest men?
  • Is virile behavior effeminate?
  • Do alleged facts often require verification?
  • Do pestilences ordinarily bestow great benefit?
  • Are painters ever artless individuals?
  • Do the defenders of citadels sometimes capitulate?
  • Do physicians ameliorate pathological conditions?
  • Is embezzlement a serious misdemeanor?
  • Do vagrants commonly possess immaculate cravats?
  • Are "loquacious" and "voluble" opposite in meaning?
  • May heresies arise among the laity?
  • Are piscatorial activities necessarily lucrative?
  • Do tendrils terminate in cerebral hemorrhages?
  • Does a baby cry?
  • Can a hat speak?
  • Do hens lay eggs?
  • Is a stone soft?
  • Is one more than seven?
  • Do the land and sea look just alike?
  • Are some books black?
  • Does water run up hill?
  • Are stamps used on letters?
  • Do 100 cents make a dollar?
  • Are we sure what events will happen next year?
  • Do ships sail on railroads?
  • Do stones float in the air?
  • May meat be cut with a knife?
  • Are ledges common in mountain districts?
  • Does success tend to bring pleasure?
  • Are diamonds mined in mid-ocean?
  • Is misuse of money an evil?
  • Should criminals forfeit liberty?
  • Is special information usually a disadvantage?
  • Are attempted suicides always fatal?
  • Are exalted positions held by distinguished men?
  • Does confusion favor the establishment of order?
  • Is a civil answer contrary to law?
  • Is a dilapidated garment nevertheless clothing?
  • Are textile manufacturers valueless?
  • Do thieves commit depredations?
  • Does close inspection handicap accurate report?
  • Do transparent goggles transmit light?
  • Do illiterate men read romances?
  • Is irony connected with blast furnaces?
  • Do avalanches ever descend mountains?
  • Are scythes always swung by swarthy men?
  • Do pirates accumulate booty?
  • Are intervals of repose appreciated?
  • Are intermittent sounds discontinuous?
  • Is an avocational activity ordinarily pleasurable?
  • Are pernicious pedestrians translucent?
  • Are amicable relationships disrupted by increased congeniality?
  • Are many nocturnal raids surreptitiously planned
  • Are milksops likely to perpetrate violent offenses?
  • Are "precipitancy" and "procrastination" synonymous?
  • Is snow cold?
  • Can a dog read?
  • Do houses have doors?
  • Has a horse five legs?
  • Are three more than ten?
  • Do mice love cats?
  • Does a hat belong to you?
  • Do animals have glass eyes?
  • Should fathers provide clothing for children?
  • Is it true that lead is heavy
  • Do poor men have much money?
  • Is summer colder than winter?
  • Can a horse tell time by a watch?
  • Is a city larger than a country town?
  • Does Christmas ever fall on Tuesday?
  • Do Christians often overlook faults?
  • Are difficult problems easily solved?
  • Do convicts sometimes escape from prison?
  • Should the courts secure justice for everybody?
  • Are scoundrels always intoxicated?
  • Is a guitar a kind of disease?
  • Do jugglers furnish entertainment?
  • Should we build on insecure foundations?
  • Do annual conventions take place biweekly?
  • Does persistent effort favor ultimate success?
  • Is a shrewd man necessarily admired?
  • Is manual skill advantageous?
  • Are elaborate bonnets inexpensive?
  • Are petty annoyances irritating?
  • Are false arguments valid?
  • Do you approve of ruthless massacres?
  • Do blemishes occur in complexions?
  • Is air found in a complete vacuum?
  • Do robins migrate periodically?
  • Are weird tales sometimes gruesome?
  • Do felines possess locomotor appendages?
  • Do demented individuals frequently have hallucinations?
  • Are laconic messages sometimes verbose?
  • Are perfunctory endeavors usually efficacious?
  • Would a deluge extinguish a smouldering trellis?
  • Are devastated suburbs exhilarating vistas?
  • Are "contingent" and "independent" alike in meaning?

[h/t Futility Closet]

10 Not-So-Small Facts About the Volkswagen Beetle

While Volkswagen has announced—for a second time—that it's going to cease production on the Beetle, people are still singing the praises of the quirky little car. Here are 10 not-so-small things you need to know about the German car that was once named one of the top four cars of the century.


Adolf Hitler checks out a VW Beetle
Getty Images

It’s long been said that Adolf Hitler was the man behind the Beetle, and that’s sort of true. The dictator wanted German families to be able to afford a car, so he enlisted automaker Ferdinand Porsche (yes, that Porsche) to make “the people’s car.” But the basis for the Beetle had been around since long before Hitler’s demand; the Bug was heavily influenced by Porsche's V series. Rumors that Hitler directly designed the car are probably false; though he was the one who reportedly said that the car should look like a beetle, because “You only have to observe nature to learn how best to achieve streamlining,” it’s likely that he was regurgitating something he had read in an automotive magazine. Still, one thing is for certain: Hitler himself placed the cornerstone for the Porsche factory in Wolfsburg, Germany.


Perhaps still wary of anything imported from Germany, Americans shunned the Beetle when it was introduced in the States in 1949: Only two were sold in the first year. But after that, sales grew quickly. By the 1960s, hundreds of thousands of Bugs were sold every year, topping out at 570,000 in 1970.


A pink VW Beetle

We have the public to thank for the car’s distinctive nickname. Originally known as the Volkswagen Type 1, the car’s curves and rounded top led to its later, insect-like moniker. Volkswagen must have realized they had a good thing on their hands, because they started referring to the car as the VW Beetle in the late 1960s.


The UK and the U.S. aren’t the only countries that bestowed a new name on the Volkswagen Type 1. In France, it's called Coccinellewhich means ladybug. It's Maggiolino and Fusca in Italy and Brazil, respectively, both of which mean "beetle." Mexico calls it Vocho; it's Peta (turtle) in Bolivia; and Kodok (frog) in Indonesia. 


In 1999, Advertising Age declared the car's not-so-small ad campaign to be the best campaign of the last 100 years, besting Coca-Cola, Marlboro, Nike, and McDonald’s. The quirky concept and copy—which, according to Advertising Age, “Gave advertising permission to surprise, to defy and to engage the consumer without bludgeoning him about the face and body”—was a game-changer for the entire industry.

The "Think Small" line and accompanying self-deprecating copy was written by Julian Koenig, who was also responsible for naming Earth Day and coming up with Timex’s “It takes a licking and keeps on ticking” tagline. He’s also half-responsible for daughter Sarah Koenig, whom you may know from NPR’s This American Life and Serial.


Herbie the Love Bug

Because of their distinctive aesthetic, VW Bugs have been associated with everything from the Beatles to Transformers. A few highlights:

  • The Beetle with the license plate “LMW 28IF” on the cover of The Beatles' Abbey Road album was sold at an auction for $23,000 in 1986. It is now on display at Volkswagen's AutoMuseum at the company’s headquarters in Wolfsburg, Germany.
  • The Fremont Troll sculpture in Seattle, a huge statue lurking under the Aurora Bridge, clutches an actual VW Beetle. An in-progress picture shows that the car was once red. It also once contained a time capsule of Elvis memorabilia, which was stolen.
  • The Herbie the Love Bug series was a big hit for Disney in the late 1960s and early 1970s. One of the original Herbies sold for $126,500 at an auction in 2015.
  • In the original Transformers cartoon, Bumblebee transformed from a VW Bug. The car was changed to a Camaro for the live-action movies.


The so-called “blumenvasen,” a small vase that could be clipped to the dashboard, speaker grille, or windshield, was porcelain when it was originally offered. The nod to flower power became such a symbol of the car that it was incorporated into the 1998 redesign. Sadly, it didn’t make the cut for the most recent overhaul: The vase was eliminated in 2011 by marketing execs apparently seeking to make the car more male-friendly.


When the millionth VW Beetle rolled off the line in 1955, the company capped the achievement by plating the car in gold and giving it diamante accents. They also created a Bug with a wicker body in collaboration with master basket-maker Thomas Heinrich.


After WWII, the VW factory in Wolfsburg, Germany, was supposed to be handed over to the British. No British car manufacturer wanted to take responsibility for the company, though, saying that "the vehicle does not meet the fundamental technical requirement of a motor-car," "it is quite unattractive to the average buyer," and that "To build the car commercially would be a completely uneconomic enterprise." Whoops.


The last VW Bug
Getty Images

Beetle #21,529,464—the one celebrated by the mariachi band—is now at Volkswagen's AutoMuseum.


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