Owners of mixed-breed dogs often say their pets are inherently healthier and more intelligent than purebreds. But ask dog breeders, and they'll likely point to the meticulous testing and matching they undergo to ensure a healthy, well-behaved dog.

Few studies have been done that extensively compare mixed breeds and purebreds, but one thing is for sure: Purebreds tend to get a lot more attention. These dogs often sell for thousands of dollars, and only purebreds are eligible to compete in the annual Westminster Kennel Club Dog Show.

But mixed-breeds still get their time in the spotlight. In honor of National Mutt Day (Dec. 2), check out these five famous mutts who have made their mark on history.

Higgins

One of the best-known dog actors of the 1960s, Higgins was a mixed spaniel adopted from a Burbank, Calif., shelter by animal trainer Frank Inn, who said he was taken by the pup’s expressive face. Higgins’ first role was on the television show “Petticoat Junction,” and he did so well that he appeared in six of the show’s seven seasons. Higgins had an extraordinary ability to convey a broad range of emotions through his facial expressions. Inn said that Higgins was the smartest dog he'd ever worked with, noting that during his time on TV, he learned one new trick or routine a week and retained those routines for years. Higgins also made cameos in “Green Acres” and “The Beverly Hillbillies,” but he’s best known for his starring role in the 1974 movie “Benji.”

Bobbie

While on a family road trip in Indiana in 1923, Bobbie, a 2-year-old collie/shepherd mix, was separated from his owners. Unable to find their dog, the family returned to their Oregon home, but six months later Bobbie showed up on their doorstep, scrawny and with his feet worn to the bone. They figured he must have walked the 2,550-mile trip home, and when the media got wind of it, the dog became a star. Nicknamed “the wonder dog,” Bobbie played himself in a 1924 silent film titled “The Call of the West,” and when he died in 1927, Rin Tin Tin laid a wreath on his grave.

Sinbad

Chief Dog Sinbad, was a mixed-breed canine member of the U.S. Coast Guard who served 11 years aboard USCG Cutter George W. Campbell and even saw combat during World War II. Chief Boatswain's Mate A. A. Rother of the ship got Sinbad as a gift for his girlfriend, but she couldn’t keep him, so Rother enlisted him in the service. He signed the dog’s paw print on the official paperwork, which meant that Sinbad wasn’t a pet, but a full-fledged member of the Coast Guard.

No one knows exactly what Sinbad’s heritage was, but an article on the dog that appeared in Life magazine described him as “liberty-rum-chow-hound, with a bit of bulldog, Doberman pinscher, and what-not. Mostly what-not."

Spike

Animal trainer Frank Weatherwax discovered this mastiff/Labrador mix at a California shelter and began training him as a puppy. Eventually, Spike became one of Weatherwax’s biggest stars — in both senses of the word. Not only did Spike grow to 170 pounds, but he also starred in the 1957 film “Old Yeller” and appeared in the 1959 movie “A Dog of Flanders” and on “The Mickey Mouse Club.”

Laika Picked up on the streets of Moscow, Laika was a mixed-breed dog said to have been part husky and part terrier. She was trained alongside two other dogs and then chosen to be placed aboard the satellite Sputnik 2 in 1957 and become the first animal to orbit the Earth. Sadly, the Soviets didn’t plan for Laika to return. The dog died when her cabin overheated and her remains incinerated when the satellite returned to Earth. Although Laike didn’t survive, she had a lasting legacy. The world was outraged by her death, which fueled debates on the welfare of animals and using them as test subjects. Today, a memorial to Laika and other Soviet cosmonauts stands in Moscow.

All photos: Wikimedia Commons

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