Polydactyl – which is derived from a Greek word meaning ‘many,’ refers to cats that have extra digits on their feet. This is a congenital abnormality that is found in all animals, including humans. Polydactyly is a genetic mutation caused by what is known as a dominant gene. This means that only one parent needs to be polydactyl to produce kittens with extra digits.
A polydactyl cat can have up to seven digits on one paw. Generally, extra digits do not cause a problem. However, sometimes an extra claw can develop between toes and if not regularly trimmed, can become ingrown. For this reason, they require more frequent trimming than normal toes.
The trait is almost non-existent in certain parts of Europe, where historically, these unusual looking cats were associated with witches and killed as a result. In Norway, they are known as “ship’s cats,” because it was believed that their extra toes would give them better balance on the stormy seas. Another reason they were kept on boats was that sailors thought them to be superior mousers. They likely reached North American by travelling on ships with early British settlers, this explains their large population in the Eastern states.
Polydactyl cats have their place in history. Perhaps most famously, Ernest Hemmingway owned a female six-toed cat named Snow White. She was given to him as a gift from a ship’s captain in the 1930’s. Hemingway was unwell as a child, spending many hours in bed, and cats became a source of comfort to him. As an adult, he admired their independent spirit, so much so that he left specific instructions in his will to look after his cats after he died. Presently, Hemmingway’s former house in Key West, Florida serves as a museum and is the home of many descendants of Hemmingway’s original polydactyl cat.
Written by Dr. Jane MacLellan, DVM