[CAT] "How fancy cats evolved: The science of our most adorable pets"

[rfmcdonald]

Salon features an excerpt from Richard C. Francis' new book on evolution, Domesticated: Evolution in a Man-Made World.

A number of fancy cat breeds began with a mutation—often confined to one individual in a litter—that had an obvious effect on the phenotype. The Scottish Fold, for example, was founded by a barn cat from Perthshire, Scotland, with peculiarly forward-bending ears. Someone decided it would be a good thing to perpetuate this mutation. The Manx, from the Isle of Man, has a skeletal mutation that causes the tailless condition, among its other effects. In this it somewhat resembles the Japanese Bobtail, a natural breed with a quite different mutation. Munchkin cats have a mutation that causes limb shortening analogous to that of the dachshund.

Polydactyl cats have extra toes and constitute a recognized breed in the United States, called the American Polydactyl. They seem to have originated in southwest England, from where they made the Atlantic crossing by ship to New England, where they are especially abundant. One important reason for their early success was the widespread belief among sailors that they brought good luck—another example of the role of human caprice in the domestication process. The record for polydactyly is 27 toes, set by a Canadian cat. Here’s hoping that the record isn’t broken.

There is another mutation, called radial hypoplasia (RH), or “hamburger feet,” which results in a different form of polydactyly, of a spiraling nature. A creative breeder in Texas sought to build on this deformity in constructing a “Twisty cat” breed, in which the spiraling extends to the bones of the forelimb. Twisty cats also have extremely short forelimbs and relatively long hind limbs, which cause them to sit like a squirrel—hence an alternative name, “squitten.” Twisty cats are banned in Europe on humanitarian grounds, but not in the United States; the same is true of the Munchkin. It is time that the United States caught up with the United Kingdom in this regard. The deliberate breeding of skeletally deformed breeds is unconscionable.

Some of the oddest-looking breeds result from a mutation that causes hairlessness. Actually, these cats aren’t completely hairless; they just look that way. The first such breed originated in 1966 from a single naked kitten, appropriately named Prune. It is a mystery to me why anyone would want to perpetuate this condition; I suspect it is simple neophilia.

Given the climate there, it is particularly perverse that the Sphinx is a Canadian breed. But then, two other notable hairless breeds, the Donskoy and Levkoy, were created in Russia and Ukraine, respectively. One hopes they are indoor cats. Other cat breeds were founded by less drastic mutations of the coat, including the Cornish Rex (downy hair), Devon Rex (short guard hair), Iowa Rex (dreadlocks), and American wirehair (dense wiry coat).

The other method for generating new cat breeds is hybridization with existing breeds. The Siamese is most commonly used as one part of the cross. For example, the Havana Brown was the result of a cross between Siamese and American shorthair, and the Himalayan represents a cross of Siamese and Persian. Second-, third-, and fourth-order hybridizations begun with Siamese hybrids and other breeds include the Ragamuffin, Ocicat, and California Spangled. Some notable hybrids that lack a Siamese component include the Australian Mist (part Abyssinian), the Nebelung (part Russian Blue), and the Burmilla (part Burmese). The Levkoy is noteworthy not only for its uncomeliness but for the fact that it was created from a cross of two mutant breeds (the ear-challenged Scottish Fold and the hair-challenged Donskoy). The mutant ante can be ever upped.