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The Dog's Ancestors
Nature Bulletin No. 333-A   February 22, 1969
Forest Preserve District of Cook County 
George W. Dunne, President
Roland F. Eisenbeis, Supt. of Conservation


The dog, often called "man's best friend", is also his oldest friend. About 10,000 years ago, when Stone Age men began to cultivate plants for food, they also began to domesticate some of the wild animals: first the dog, then the pig, followed by cattle and reindeer, sheep, goats, asses, horses, camels and elephants -- in about that order. Scientists differ but most agree that Fido is descended from the wolves of Europe and Asia, perhaps tamed at different times in different parts of the world. They enjoyed the discarded food and the warmth of the campfire, repaying their masters by giving notice of the approach of enemies and by assisting in the hunts for game.

The prehistoric ancestor of the dog tribe was a small mink-like animal, with a long body and short legs, which lived about 40 million years ago where there were three-toed horses no bigger than a sheep. From it, through the ages, developed a type of animal -- the bear-dog -- which gradually became gigantic and the ancestor of our modern bears: and another type from which developed two kinds of "grandchildren". One was the beginning of a line of beasts that eventually produced the wild hunting dogs now found in Africa and India, and the peculiar South American bush-dog. From the other, which was very dog-like in appearance, are descended all of our present day dogs, wolves, coyotes, jackals and foxes. From it, too, developed a carrion-eating hyena-dog which occurred only in North America and became extinct.

The dog tribe gradually developed longer legs for running down their prey, a remarkably high degree of intelligence, a surprising ability to adapt themselves to all manner of conditions and, except for the foxes which are solitary hunters, a sociability which caused them to travel in families or in packs. Like the wolves today, they tirelessly pursued game for mile after mile, hour after hour, frequently taking turns in relays until their quarry was exhausted and overtaken -- teamwork at its best.

It was this ingrained sociability and adaptability that enabled dogs to be domesticated and, by careful breeding, to produce so many different types for various purposes. On monuments of ancient Egypt there were pictured slender dogs of the greyhound type and another short-legged breed. Today there are over 200 known breeds generally classified into six groups: the sporting dogs, the hounds, the working dogs, the terriers, the toy dogs, and the non-sporting miscellaneous kinds. The Indians of western Canada developed a strain with white wooly hair which was excellent for weaving.

It is believed that America was first peopled by men from Asia and that they brought their dogs with them. No earlier record exists but in the prehistoric Indian mounds of the Ohio valley there are remains of dogs. In a burial place of the Basket Makers who lived in our Southwest about 2000 years ago, were found the mummies of two types of dogs. Before the white man brought horses from Europe, dogs -- apparently crossed with native wolves or coyotes -- were the Indians' only beasts of burden. They were trained to carry a heavy back-pack or drag a travois of wooden poles. Among many tribes they also served as food, especially at feasts before and after a warring expedition.

After 10,000 years, however, Fido still turns around a few times before lying down, buries bones, howls at night, and yaps or bays when on a hot trail. He is color blind but his nose is keen. He lives in a world of smells.

Just watch him, sometime. That's a dog's life !

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