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Le puppy - It's believed that the English word "puppy" may come from poupeé, a French word meaning doll or toy.

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Some puppies are born green -

This can happen when the fur gets stained by biliverdin, a green pigment found in dog placentas. The green hue is not permanent and eventually disappears, usually after a few weeks.

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They manipulate you with "puppy eyes" -

Puppies and dogs alike know how to look adorable and the impact it has in humans.

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Looking at puppies can make you more productive -

According to one study, people who look at photos of puppies and kittens have an easier time focusing and performing tasks.

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A puppy almost ruined John Steinbeck's career -

A puppy destroyed half of the author's 'Of Mice and Men' manuscript. The Nobel and Pulitzer Prize-winner had to rewrite half of the book!

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They don't find our yawns contagious -

Unlike humans, there is no such thing as contagious yawning for puppies. They do develop these empathetic yawns as dogs, but as puppies they don't.

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Lassie wasn't an easy puppy -

Pal, the first dog to play Lassie on film, had a few behavior issues as a pup. Pal wouldn't stop barking, and enjoyed chasing down motorcycles.

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They sleep a lot -

Puppies take lots of naps. In fact, they can sleep up to 15-20 hours a day! This is essential for the development of their brains, muscles, and immune system.

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A song in 'Hamilton' was inspired by a puppy -

In the Broadway musical, Aaron Burr and Alexander Hamilton sing a ballad to their newborn children. But according to Lin-Manuel Miranda, the inspiration for the song was an adopted dog and not a baby.

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They can't hear or see when they're born -

Puppies are blind and deaf when they're born. Usually the ear canals begin to open at about the same time their eyes do, a few days later.

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Who's a good boy?  -

Research has found that, unlike older dogs, puppies do like baby talk!

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There's a 17-ton sculpture of a puppy in Spain -

The 40-foot- (12.40-m-) tall sculpture, called 'Puppy,' is covered with 37,000 live flowers. It can be found at the Guggenheim Museum in Bilbao.

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They have baby teeth - Puppies are born toothless and then develop baby teeth. These usually fall out when they're around 12 to 16 weeks old.

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Litter size depends on the breed -

Some dog breeds have bigger litters than others. The Guinness World Record belongs to Tia, a Neapolitan mastiff that had 24 puppies.

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The Obamas' puppy had his own baseball card -

In 2009, the Obamas adopted a six-month-old Portuguese water dog named Bo. A few months later, they issued an official baseball card with fun facts about Bo.

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They can have identical twins -

Although not proven until 2016, identical twin puppies do exist. This happens when two puppies' umbilical cords attach to a single placenta.

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Keith Richards smuggled a puppy through customs -

The Rolling Stones guitarist was flying back to the UK from the US with a collie puppy named Ratbag. The animal was supposed to be quarantined, but he smuggled him through UK customs under his coat.

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Space dogs -

In the 1960's, a dog named Strelka (right) became famous for going into orbit as part of the Soviet space program.

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Space dogs -

Some time later, Soviet Premier Nikita Khrushchev sent the Kennedys one of Strelka's puppies. She was named Pushinka (right).

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A puppy was "hired" by a museum to find unwanted pests -

In 2018, Boston's Museum of Fine Arts got a Weimaraner puppy named Riley to "patrol" for pests that could be harmful to masterpieces. (e.g. textile-eating moths and wood-boring beetles).

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A computer is judging guide puppies -

IBM has developed a program for their supercomputer 'Watson' that helps predict how likely each puppy is to graduate from Guiding Eyes for the Blind, a training school for guide dogs. 

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Dalmatian puppies are born without spots -

Many are born with a few patches, but only develop their distinctive spots later in life.

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Some breeds are born by C-section -

This is particularly true for breeds with very large heads, like this English mastiff.

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Our ancestors took good care of dogs -

A 2018 study on a fossilized jaw, estimated to belong to a 27 or 28-week-old puppy, found that the animal suffered from canine distemper virus.

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Our ancestors took good care of dogs -

The fossil, which dates back to around 14,000 years ago, shows that the dog survived longer than expected, meaning it was well cared for by humans.

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Puppy Bowl is not live -

Contrary to popular belief, Animal Planet's 'Puppy Bowl' is not broadcast live. It is actually filmed over the course of a week.

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First cloned puppy -

In 2005, an Afghan hound named Snuppy was the first dog to be cloned.

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Cloned puppies -

Dog cloning is now possible in many countries, so you can have your puppy again a few years down the line.

Sources: (PLOS) (Reproduction in Domestic Animals) (Journal of Archaeological Science)

See also: These 60 breeds make the best family dogs

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