By Dr. Becker
Cats with polydactyly, which means “many digits,” have a genetic mutation that gives them extra toes. Typically, cats have 18 toes, five on their front paws and four on the back. Polydactyl cats have extras, which lends an endearing charm to these “big-footed” felines.
The cats are sometimes called “Hemingway cats,” because the famous writer Ernest Hemingway had a penchant for polydactyl cats. A ship’s captain gave Hemingway his first six-toed cat, which he named Snow White, and today 40 to 50 polydactyl cats still live at The Earnest Hemingway Home and Museum in Key West, Florida.1
While some genetic mutations are considered to be a hindrance, the polydactyl trait can be an asset to cats. It doesn’t typically cause them any discomfort, and their extra toes draw in many human admirers. Historically, sailors considered the cats, which they called “gypsy cats,” to be good luck.
On the high seas, their extra toes provided superior balance and gave them an advantage in hunting mice. It’s thought that their close connections with sailors may be one reason why polydactyl cats are found all over the world today.
While any cat breed can be polydactyl, the trait is seen most often in western England, Wales, the eastern U.S. and Canada.2
Intriguing Facts About Polydactyl Cats
1. It’s a Genetic Mutation, Not a Breed
Aside from Maine Coons, which at one time had an extraordinarily high rate of polydactyly among the breed (about 40 percent),3 no cat breed is more likely to have extra toes than others.4
It’s not linked to a breed of cat, rather it’s a genetic mutation. If a polydactyl cat breeds with a normal cat, about 40 to 50 percent of the resulting kittens will be polydactyl. While you may hear of the American polydactyl and the Maine Coon polydactyl breeds, they’re not officially recognized.
It’s thought that Maine Coons may have, at one time, been predisposed to polydactylism because the extra toes made their feet wider, like snowshoes, helping them to walk on snowy ground.5
2. Some Polydactyl Cats Have ‘Thumbs’
In most cases, a polydactyl cat’s extra toes look just like the others, giving them the appearance of having large feet. But in the case of thumb cat polydactyly, the first digit (dewclaw) is large and thumb-like. These cats are sometimes called “mitten cats” because it looks like they’re wearing mittens.
Polydactyl cats can have a varying number of extra toes; Jake, the Guinness World Record holder for most toes on a cat, had 28 toes.
3. A Polydactyl Cat Named Slippers Lived in the White House
Ernest Hemingway wasn’t the only famous person to love polydactyl kitties. President Theodore Roosevelt also had a poly cat, which was named Slippers and accompanied him to the White House.
4. The Genetic Condition Feline Radial Hypoplasia Is Associated With Extra Toes
In most cases, the polydactyl mutation is a harmless one (although it can make trimming your cat’s nails a challenge). The exception is when the mutation occurs along with feline radial hypoplasia, a genetic condition that often involves extra toes along with forelegs that are short and twisted.
Can Other Animals Be Polydactyls?
Polydactyly is not a condition that’s unique to cats. It can also occur in dogs, mice, moles and even humans. Oftentimes, the extra digit contains no joint and is simply a non-functional digit composed of soft tissue and some bone.
The Norwegian Lundehund, or Norwegian puffin dog, for instance, has at least six toes on each paw, which helped it to navigate cliffs while retrieving puffin birds (most dogs have five toes on their front feet and four on the back).6 Great Pyrenees also have extra toes.
Keeping your pet’s nails trimmed is always important, but it becomes even more crucial on polydactyl animals. Depending on the placement of the toes, the nails may not become worn down with typical running, jumping or scratching/digging, and left to grow too long may become embedded in the foot or pad.
Be sure you’re aware of each of your polydactyl animal’s toes, and which direction the nail grows, and keep them trimmed as necessary.