Dear Straight Dope:
When we lived in Massachusetts, we adopted two cats, Bridget and her mother Shaya. Both these cats (as well as most of Bridget's litter) have double paws in front. Not extra toes but a whole other paw with 3 to 4 toes. The usefulness of each of these paws and toes varies. We asked a vet in Massachusetts about this. Her response began with "If this isn't true, it oughta be." The story she told was basically this: During the time of sailing ships, the English captains considered double-pawed cats lucky. So whenever one was born in England, it was given/sold to them. Boston, being the port at the time (remember this was a New Englander telling the story), was their destination and the cats would run around loose and do whatever a cat needs to do. She said this trait was somewhat common in New England but I wouldn't find it elsewhere. I never heard of such a phenomenon before. Any truth to this story?
"If this isn’t true, it oughta be." Words to live by, in my opinion.
Cats normally have 18 digits, four on each hind foot and five on each front foot. A polydactyl cat will usually have one or two extra toes on each front paw. Some have as many as eight or even ten digits on each foot, appearing to be a whole extra paw. I saw X-ray photos in one veterinary journal. Very interesting to see. Interesting to see in the flesh, too, and I should know, because I had a cat like that once. Jessie had what appeared to be almost double paws–there was a gap between the sets of toes.
The forefeet are most often affected and they can have extra dewclaws as well. (A dewclaw is the vestigial claw higher up on the leg in the back.) The condition is inherited as an autosomal (non-sex-related) single dominant trait. If one parent cat has polydactylism, 40-50% of the kittens will inherit it.
Polydactyly (Greek: poly=many, daktulos=fingers) is more common among New England cats, and some people say "mitten footed cats" originated there. Several sources I checked recounted the story you told, that ships’ captains carried them onboard because they were considered lucky (and better mousers, one source said). An article from Cornell University’s Cat Watch (1998) looked at studies done on polydactyl cats from the 1940s to the 1970s, and tentatively concluded that the trait probably initially occurred in cats who came over from England to the Boston area with the Puritans in the mid 1600s. There was also speculation in the article that the mutation might have developed in cats already in the Boston area, and descendants of those cats were carried aboard trading ships to the Halifax, Yarmouth MA, and Nova Scotia areas, which now have sizable multi-toed cat populations.
Researchers taking censuses on polydactyl cats (now there’s a job: "Hold on a minute, didn’t we already count that black and white one over by the dumpster there?" "Jesus, Steve, hurry up and count the paws, he’s scratching the hell out of me") found that there were greater populations in the Boston area than in New York City or Chicago. In Europe, polydactyl cats are rare because they were practically wiped out during medieval times due to superstitions about witchcraft (Kelly, Larson, 1993).
One of the oldest breeds of cats in North America is the Maine Coon Cat, and some say 40% of the originals had extra toes. One article said it evolved as a "snowshoe foot" to help these cats walk in the snow. Cute story, but probably bullshit, my earlier "words to live by" notwithstanding.
The official cat club people disqualified poly-toed Maine Coon Cats from competition in purebred classes by making the trait a deviation from "Breed Show Standard." Oh, the uproar then about polydactyl Maine Coon Cats being an important part of American heritage! The AFCA and other cat registries (CFA, TICA, CFF, MCBFA) later added a "Household Pet" class that allowed the trait, and now some cat fanciers breed specifically for it. You can just imagine the cat fighting over this issue.
(Are there a lot of websites out there all about cats? And pictures of people’s personal cats? Uh, yeah. Not to mention the first person accounts: "My name is Mitzi and I’m a Maine Coon Cat. I drive my family crazy with my zany antics…" Meanwhile in Bosnia … never mind, back to the topic at hand.)
The breed closest to the Maine Coon Cat is the Norwegian Forest Cat which evolved in the same climate and lends credence to one theory that ancestors of the Coon Cat may have even come to the New World onboard Viking ships. I like that theory best. You also have your polydactyl cat breed in the Pacific Northwest, called the Pixie Bob, but let’s not make this story any more complicated than it already is.
Famous polydactyl cats in history:
According to a site I found on Maine Coon Polydactyls, President Theodore Roosevelt had a poly named Slippers, who was one of the first feline residents in the White House. Ernest Hemingway was given a polydactyl Maine Coon Cat when he lived in Key West, Florida by one of his drinking buddies, a sea captain named Stanley Dexter. There are many polys–descendants of Papa’s–at his estate in Key West, which is open to the public.
Turns out there is a polydactyl dog, too. The Lundehund, one of the oldest and rarest breeds of dogs, has six toes on each foot, which apparently helped it climb steep scree slopes. Lundehunds were bred to hunt puffins (lunde = puffin) for Norweigan fishermen on the Lofoten islands. This dog, among other unusual characteristics, has one less tooth on each side of its jaw. But don’t get me started. Somebody ask a Lundehund question and I’ll go on!
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