25 Facts About Puppies

Everyone loves puppies, we know. It's scientifically proven that they're heart-meltingly cute. But there's more to the little fur babies than just those adorable puppy eyes. In honor of National Puppy Day (which happens on March 23), here are 25 things everyone should know about these four-legged snuggle buddies.

1. THE WORD PUPPY HAS FRENCH ROOTS.

Etymologists think the term puppy may come from poupeé, a French word meaning doll or toy. The word puppy doesn't appear to have entered the English language until the late 16th century—before that, English speakers called baby dogs whelps. William Shakespeare's King John, believed to be written in the 1590s, is one of the earliest known works to use the (super cute) term puppy-dog.

2. PUPPIES EVOLVED TO BE BLIND AND DEAF AT BIRTH.

Puppies are functionally blind and deaf at birth. On day one, their eyes are firmly shut and their ear canals closed. Why? In brief, it’s part of an evolutionary trade-off. Since pregnancy can hurt a carnivore's ability to chase down food, dogs evolved to have short gestation periods. Brief pregnancies meant that canine mothers wouldn't need to take prolonged breaks from hunting. However, because dog embryos spend such a short time in the womb (only two months or so), puppies aren't born fully developed—and neither are their eyes or ears.

3. PUPPIES HAVE BABY TEETH, TOO.

Like many newborn mammals, puppies are born completely toothless. At 2 to 4 weeks of age, a puppy's 28 baby teeth will start to come in. Around 12 to 16 weeks old, those baby teeth fall out, and by the time pups are 6 months old, they should be sporting a set of 42 adult teeth.

4. PUPPIES TAKE A LOT OF NAPS.

Like children, puppies need a lot of sleep—up to 15 to 20 hours of it a day. The American Kennel Club strongly advises dog owners to resist the urge to disturb napping puppies, because sleep is critical for a young canine's developing brain, muscles, and immune system. Puppy owners should also establish a designated sleeping space on their pup's behalf so they can snooze undisturbed.

5. CERTAIN dog BREEDS ARE USUALLY BORN BY C-SECTION.

Purebred dogs can exhibit some extreme bodily proportions, which doesn't always make for easy births. Breeds with atypically large heads are more likely to be born by C-section than those with smaller skulls. A 2010 survey of 22,005 individual dog litters in the UK found that terriers, bulldogs, and French bulldogs had Caesarian births more than 80 percent of the time. The other breeds with the highest rates of C-sections were Scottish terriers, miniature bull terriers, Dandie Dinmont terriers, mastiffs, German wirehaired pointers, Clumber spaniels, and Pekingeses, according to the study.

6. SOME dog BREEDS HAVE BIGGER LITTERS THAN OTHERS.

As a general rule, smaller breeds tend to have smaller litters, while bigger dogs give birth to more puppies. The biggest litter on record was born to a Neapolitan mastiff that gave birth via Caesarian section to a batch of 24 puppies in Cambridgeshire, UK in 2004. In rare cases, very small dogs do give birth to relatively large litters, though. In 2011, a Chihuahua living in Carlisle, England, gave birth to a whopping 10 puppies—twice as many as expected. Each weighed less than 2.5 ounces.

7. SOME PUPPIES ARE BORN GREEN.

Sometimes, a puppy in a light-colored litter can be born green. On two different occasions in 2017, in fact, British dogs made the news for giving birth to green-tinted puppies. In January, a 2-year-old chocolate lab in Lancashire, UK gave birth to a litter that included a mossy-green pup. Her owners named her FiFi, after Fiona, the green-skinned ogre from Shrek. Just a few months later, a golden retriever in the Scottish Highlands also gave birth to a puppy with a green coat, a male named Forest. How did the puppies end up sharing a shade with Kermit? In rare cases, the fur of a light-haired puppy can get stained by biliverdin, a green pigment found in dog placentas. It's not permanent, though. The green hue gradually disappears over the course of a few weeks.

8. PUPPIES DON'T FIND YOUR YAWNS CONTAGIOUS.

Ever notice that when somebody yawns, other people may follow suit? Contagious yawning, thought to be a sign of empathy, affects humans, baboons, chimps, and yes, dogs. But as research published in Animal Cognition suggests, young canines aren't susceptible to catching yawns from birth. In the 2012 study, Swedish researchers took a group of 35 dogs between 4 and 14 months old on closely monitored play dates, feigning yawns in front of each individual animal. Dogs that were less than 7 months old didn't react, yet many of the older dogs would respond with a yawn of their own. This pattern mirrors what happens with humans—children don't pick up the habit of contagious yawning until around age 4, when they start to develop social skills like empathy. These results suggest that dogs, too, may develop empathy over the course of their puppyhood.

9. PUPPIES LIKE "BABY TALK" MORE THAN THEIR PARENTS DO.

Like humans, puppies seem to grow out of baby talk, recent research has found. As part of a 2017 study, 30 women were asked to look at assorted photographs of people and dogs and utter this pre-written line: "Hi! Hello cutie! Who's a good boy? Come here! Good boy! Yes! Come here sweetie pie! What a good boy!" To the surprise of no one, the human test subjects spoke in a higher register while looking at dog pictures, especially puppy photos. Afterward, the researchers played the recordings for 10 adult pooches and 10 puppies. Almost all of the pups started barking and running toward the speaker when they heard the baby-talk recordings. In contrast, the grown dogs pretty much ignored the recordings altogether.

10. DALMATIAN PUPPIES ARE BORN WITHOUT SPOTS.

Beloved by firefighters, Disney fans, and George Washington, Dalmatians arguably have the most recognizable coat of any dog breed. Or at least, full-grown Dalmatians do. As puppies, they're born white and spot-less. The markings usually begin to show up after four weeks or so. (A small subset of Dalmatian puppies are born with one or two large black blotches, known as patches, but those markings aren't allowed in most competitive show rings.)

11. PUPPIES KNOW HOW TO MANIPULATE YOU WITH THEIR EYES.

Those adorable "puppy eyes" aren't an inadvertent expression of canine emotion; they're a deliberate ploy to get our attention. Puppies (and adult dogs) have learned that raising their eyebrows, which makes their eyes appear bigger and sadder, makes them magnets for human attention. According to one study from 2017, dogs are more likely to make dramatic facial expressions like puppy-dog eyes when they know humans are watching. And it works. Research has shown that shelter puppies who put on such faces get adopted more quickly than dogs that show other behaviors, like wagging their tails.

12. PUPPIES CAN HAVE IDENTICAL TWINS.

Scientists don't know how common identical twin puppies are, because until very recently, no one was able to prove that they existed at all. In 2016, Kurt de Cramer, a South African veterinarian, noticed something unusual while performing a C-section on a pregnant Irish wolfhound. Normally, every puppy gets its own placenta, yet de Cramer noticed that two of the seven pups in this litter shared a single placenta. Testing later verified that the puppies were genetically identical. It was the first confirmed case of identical twin puppies in the world.

13. SCIENTISTS HAVE SUCCESSFULLY CLONED (AND RE-CLONED) THEM.

In 1996, Dolly the sheep became the first successful mammal clone. Nine years later, geneticists in South Korea used the same process to engineer the world's first canine clone, an Afghan hound named Snuppy. While Snuppy passed away in 2015 at the respectable age of 10, his story isn't over yet. In 2017, researchers announced that four puppies had been cloned from his stem cells. Sadly, one of the pups died a few days after its birth, but the other three survived. Scientists hope that these young dogs will teach us how healthy cloned animals are compared to their naturally conceived counterparts.

14. LIN-MANUEL MIRANDA'S PUPPY INSPIRED A SONG IN HAMILTON.

In the award-winning musical Hamilton, Aaron Burr and Alexander Hamilton sing a ballad called "Dear Theodosia" to their newborn children. The tender song's inspiration wasn't a newborn babe, though. Lin-Manuel Miranda wrote it the week he adopted Tobillo, a stray puppy he and his wife found while on vacation in 2011.

15. A PUPPY DESTROYED HALF OF JOHN STEINBECK'S OF MICE AND MEN MANUSCRIPT.

Of Mice and Men might feature one of the biggest animal lovers in American literature—the rabbit- and puppy-loving Lennie—but ironically, a puppy once jeopardized the novel's existence. In May 1936, John Steinbeck's Irish setter, Toby, was going through his teething phase. Left alone one night, he demolished half of his master's manuscript for Of Mice and Men, eating through two months of work ... and Steinbeck didn't have any backup copies. But the author found it hard to stay angry with the puppy. "I was pretty mad, but the poor little fellow may have been acting critically," Steinbeck wrote. "I didn't want to ruin a good dog for a manuscript I'm not sure is good at all." He just buckled down and rewrote the shredded chapters.

16. KEITH RICHARDS ONCE SMUGGLED A PUPPY THROUGH BRITISH CUSTOMS.

While the Rolling Stones were on tour in the U.S. in 1964, a fan gave guitarist Keith Richards a collie puppy named Ratbag. When Richards returned to the UK, rather than subject the pup to quarantine, he smuggled the animal through British customs under his coat. The dog would become one of Richards's most beloved companions, and a biographer would later write that the star "appeared to identify more than anybody else."

17. BARACK OBAMA'S PUPPY HAS HIS OWN BASEBALL CARD.

In April 2009, the Obamas adopted Bo, a 6-month-old Portuguese water dog. That summer, the White House put together an official baseball card loaded with fun facts about America's First Pooch. (For one: He can't swim.) You can still download the collectible card online.

18. THE SOVIET UNION ONCE GAVE JFK A VERY SPECIAL PUPPY.

Dogs can bring out the best in people, including political adversaries. While seated next to each other at a state dinner in Vienna in the early 1960s, First Lady Jackie Kennedy and Soviet Premier Nikita Khrushchev got to chatting about Strelka, the world-famous dog who had recently been sent into low-Earth orbit by the Soviet space program. Afterward, Khrushchev sent the Kennedys one of Strelka's newly born daughters. The puppy's name was Pushinka, which means fluffy in Russian.

19. A BOSTON MUSEUM HAS ENLISTED A PUPPY TO FIND ART-DESTROYING PESTS.

In early 2018, Boston's Museum of Fine Arts "hired" a Weimaraner pup named Riley to find unwanted pests that, if left unchecked, could harm priceless masterpieces. Riley is being taught to sniff out art-threatening insects like textile-eating moths and wood-boring beetles. "Pests are an ongoing concern for museums," deputy director Katie Getchell told The Boston Globe in January 2018. "It's exciting to think about this as a new way to address the problem." If Riley is able to do his job well, she said, other museums and archives that collect infestation-prone materials might be able to use trained dogs as a defense against bugs, too.

20. IBM'S WATSON IS JUDGING PUPPIES NOW.

Not all puppies have what it takes to become guide dogs. Guide dogs have to be healthy, confident, hardworking, and not easily distracted. At the end of the day, many pups just aren't cut out for this line of work—at Guiding Eyes for the Blind, a nonprofit that trains and places seeing eye dogs in New York, only about 36 percent of trainee dogs make it. That's where Watson, the IBM supercomputer famous for winning Jeopardy, comes in. IBM has developed a program for Watson that helps it predict how likely individual puppies are to graduate from Guiding Eyes's training school using data on the temperament, medical history, and genetics of the dogs as well as the personality traits of their trainers. 

21. LOOKING AT PUPPIES CAN MAKE YOU MORE PRODUCTIVE.

That puppy portrait hanging in your cubicle at work might be a bigger asset than you realized. For a 2012 Hiroshima University experiment on productivity, participants were asked to look at pictures from one of three categories: tasty food snapshots, pictures of adult animals, or photos of puppies and kittens. Then, they were asked to play a board game that required lots of precision. As it turned out, people who'd just seen puppies and kittens had an easier time concentrating on the task at hand than study subjects who saw other types of images.

22. OUR STONE-AGE ANCESTORS TOOK GOOD CARE OF THEIR PUPPIES.

In 1914, archaeologists in Germany discovered the fossilized jawbone of a puppy that lived 14,000 years ago. According to a 2018 study on the specimen, the jaw probably belonged to a 27- or 28-week-old pup—and a sick one, at that. The teeth showed signs of canine distemper virus, a life-threatening disease that still has no cure. Analysis of the bone suggested that the animal first came down with the sickness at 19 weeks old. "Without adequate care," study co-author Luc Janssens noted in a press release, "a dog with a serious case of distemper will die in less than three weeks," yet this pup survived for another eight weeks. Even though the puppy wouldn't have been very useful to its prehistoric human owners, they kept it clean, warm, and well-fed for months, helping it survive for longer than it otherwise would have.

23. THERE'S A 17-TON PUPPY SCULPTURE IN BILBAO, SPAIN.

Since it opened in 1997, the Guggenheim Museum in Bilbao has been home to Puppy, a towering, flower-covered sculpture that artist Jeff Koons modeled after a young West Highland terrier. The 17-ton pooch owes its shape to a fabric-covered mesh that is topped with 37,000 live flowers. The 40-foot-tall, puppy-shaped garden is now regarded as a mascot for both the museum and the city itself.

24. THEY'RE NOT RUNNING AROUND THE PUPPY BOWL LIVE. (SORRY.)

The fur-rocious Super Bowl spoof known as the Puppy Bowl made its debut on Animal Planet back in 2005. Viewers might be surprised to find out that, unlike the real game, the Puppy Bowl isn't broadcast live. Instead, the contest is shot over the course of an entire week. The crew spends two days filming the dogs with the help of 100 or more canine wranglers. 

25. HOLLYWOOD'S MOST ICONIC DOG WAS A TROUBLESOME PUPPY.

The first dog to play Lassie on film was really a "laddie." Specifically, he was a male Rough collie named Pal. As a pup, the dog had some behavior issues—little Pal was overly enthusiastic and drove his first owner crazy with nonstop barking. (Even more disconcerting was the puppy's habit of chasing down motorcycles, a pastime he never outgrew.) After animal trainer Henry Peck failed to make any progress with Pal, he referred the puppy's owner to a colleague by the name of Rudd Weatherwax, who was much more successful at training him. Pal's original owner eventually gave him to Weatherwax, and the rest is history. Under the trainer's guidance, Pal starred in seven Lassie movies, plus two episodes of the spinoff TV series. Decades after his passing, The Saturday Evening Post declared that Pal had enjoyed "the most spectacular canine career in film history."

This story first ran in 2018.