The horse came into existence before man on earth. Although the earliest remains of primitive horses have been found on the North American continent, many scientists believe this small species traveled over a land mass. It became extinct (绝种的) in America. Other scientists believe that the horse may have originated in Asia. In any the animal soon spread into China, Europe, and the Middle East. The first modem horse to be introduced into the American continent came with the early Spanish explorers. Horses were bred into many types. The heavy horses developed in the low countries of Europe and were used for work and by the medieval knights (中世纪骑士) to fide. The oldest breed of horses is said to be the Ar. The only true wild horses left in 20th century are found in Mongolia. Horses are said to rate in intelce after the ape, the elephant, the dog. They have excellent memories and can sometimes find their way home when lost, and sense er better than their s. The early civilizations of man that had made use of the horse developed more rapidly than those which had not.
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