The animal on the cover of the jQuery Cookbook is an ermine (Mustela erminea), also known as a stoat. “Ermine” sometimes refers to the animal’s white winter fur, and “stoat” to the brown fur it has during the rest of the year. It belongs to the weasel family, which includes martens, ferrets, minks, otters, and polecats, though it is distinguished from these other members by its black-tipped tail.
The ermine lives in northern woodland regions of Europe, Asia, and North America. It is mainly nocturnal and makes dens in tree roots, under stones, and in tunnels. A solitary animal, the ermine can travel up to 10 miles in one night searching for food. Its predators include foxes, badgers, cats, and birds of prey.
The ermine’s slender body helps it run swiftly, even across snow, as well as climb and swim. Although this shape has advantages, it also causes the ermine to quickly lose heat from its body. Thick fur and a fast metabolism help compensate, and the ermine must eat daily to meet its energy demands. Its diet includes small mammals, birds, fish, and insects. When the ermine spots its prey, it sneaks up on it in a series of leaps, grasps the victim’s neck, and kills it with repeated bites.
White ermine fur is highly prized and is used in trimming coats, although demand has dropped in recent years. Typically, several furs are sewn together to form a pattern of black dots on a white field. This pattern was imitated in heraldry—the design of coats of arms—as early as the 12th century, ...