Imposters abound in the animal kingdom. Peruse any textbook description of mimicry—in which one species evolves to resemble another—and you will encounter various classic examples, such as the king snake, which copies the coral snake, or the hoverfly, which masquerades as a bee. Less familiar, but in many ways even more fascinating, are the mimics in a genus of jumping spider known as Myrmarachne, which look for all the world like ants.