The much-loved, furry tourist magnets that live at the Ernest Hemingway Home and Museum in Key West are famous for being polydactyls–they have six-toed front paws that make them look as if they’re wearing mittens. Like Fats Waller in the picture at left. Today’s New York Times has an article, “For Whom the Cell Mutates: The Origins of Genetic Quirks,” that delves into the science behind what makes a cat polydactyl, along with some insights about Hemingway and his writing. Although they care more about enticing literary travelers to pet them and napping in the garden, Fats Waller and his fellow residents have made it into science lore. “When found in felines,” the Times reports, “the condition, formally known as preaxial polydactyly, is now commonly referred to as a ‘Hemingway cat.'”