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The nearly 58 million pet dogs that live in the United States come from a wild family. Scientists call it the Canidae family. Its members, known as canids or canines, include wolves, coyotes, foxes, jackals, and wild dogs such as the bush dog, raccoon dog, Australian dingo, and African wild dog. To separate the domestic dog from its wild relatives, scientists have given it a special name—Canis familiaris, meaning “familiar dog.”
Domestic dogs come in all shapes and sizes, from the tiny Chihuahua to the tall Great Dane to the heavy St. Bernard. But if you go back far enough in the family tree, as scientists have done, you will discover that pet dogs have a common ancestor—the wolf. Nobody knows for certain how the relationship between human beings and wolves started, but it was about 100,000 years ago that the story of Canis familiaris began.
