About Polydactyl Cats

Polydactyl, or "many digits," refers to one or more extra toes on a cat's paw. Polydactyly is most common in cats residing in the Celtic countries, southwestern Britain and the east coast of the United States, and appears to occur as the result of heredity or spontaneous mutation. It is thought that polydactyl cats first arrived in the United States from Britain; in fact, polydactyly occurs commonly enough in Britain that it is not considered an abnormality. There are two forms of polydactyly: pre-axial, referring to extra digits on the inside edge (thumb-side) of the paw, and post-axial, referring to extra digits on the outer side (little finger side) of the paw. Post-axial polydactyly is rare.

  1. Hemingway Cats

    • Polydactyl cats are sometimes referred to as "Hemingway cats." Ernest Hemingway was known to share his Key West, Florida home with close to 50 cats, one of which was a polydactyl cat given to him by a ship captain. As the cats were allowed to freely roam the island, the trait soon spread throughout the local cat population. Polydactyls are also sometimes referred to as "Boston thumb cats," as Boston, Massachusetts, has a large population of these cats as well. In fact, Boston traders may have been responsible for the large polydactyl cat concentrations in Yarmouth, Massachusetts, and Halifax, Nova Scotia.

    Polydactyl Cats and the Sea

    • Norwegians refer to polydactyl cats as "ship's cats," as the extra toes are said to give the cats better balance on ships during rough weather. Sailors generally considered polydactyls to be lucky cats and welcomed them on their ships as ratters, mousers and all-around ship mascots. Given the volume of sea trade between England and the eastern United States during colonial times, this would explain the high concentrations of polydactyl cats in eastern American cities. Conversely, there is a high concentration of polydactyls in southwestern England, from which many of the ships set sail, and could be a primary point of origin of the polydactyl's migration to North America.

    Physical Characteristics

    • Polydactyl cats are said by their owners to have a peaceful and mellow nature. They are hardy enough to survive in snowy weather (the extra-toed feet act as a type of snowshoe), and can live equally well either indoors or outdoors. Their bodies are medium to large in size, rectangular in shape, and strong and muscular in appearance. Noses and muzzles are medium sized, and chins are squared. The eyes are rounded and angled on the face. Of course, the major identifying feature of a polydactyl cat is its extra toes. One conformation has the extra toe placed on the paw like a human thumb; another has an extra set of three toes attached to the four-toed foot.

    Genetics

    • Polydactyly is the result of a dominant gene; in other words, the kittens born of a polydactyl mother will have the extra toes even if the father is not polydactyl. The gene results in either extra toes or extra dewclaws (a toe or thumb-like digit on the inside of the foot that does not touch the ground). Polydactyly is more common in cats than in other mammals, which may originate from the location of specific genes on chromosomes as some areas on the chromosome are more prone to mutation than others. While polydactyly in general is not harmful to a cat, there is a "bad" form of polydactyly, as some genetic mutations result in a general disruption of a kitten's limb formation in embryo, causing disabling twisting in the forearms.

    Polydactyls in the Wild

    • Polydactyly does not occur solely in domesticated cats. For obvious reasons, it has not often been noted in the largest members of the feline species. During the first half of the twentieth century, big game hunters reported finding (and shooting) polydactyl leopards in the wild. What made the leopards' polydactyly unusual was its occurrence in the hind paws only. In domesticated cats, the hind paws are affected only if the front paws are as well.