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The development of the horse has been recorded from the beginning through all of its evolutionary stages to the modern form. It is, in fact, one of the most complete and well-documented chapters of paleontological history. Fossil finds provide us not only with detailed information about the horse itself but also with valuable insights into the migration of herds, and even evidence for speculation about the climatic conditions that could have instigated such migratory behavior.
Geologists believe that the first horses appeared on Earth about sixty million years ago as compared with two million years ago for the appearance of human beings. There is evidence of early horses on both the American and European continents, but it has been documented that, almost twelve million years ago at the beginning of the Pliocene Age, a horse about midway through its evolutionary development crossed a land bridge where the Bering Strait is now located, from Alaska into the glasslands of Asia, and traveled all the way to Europe. This early horse was a hipparion, about the size of a modern-day pony with three toes and specialized cheek teeth for grazing. In Europe, the hipparion encountered another less advanced horse called the anchitheres, which had previously invaded Europe by the same route, probably during the Miocene Period. Less developed and smaller than the hipparion, the anchittheres was eventually completely replaced by it.
By the end of the Pleistocene Age both the anchitheres and the hipparion had become extinct in North America, where they had originated, as fossil evidence clearly indicates. In Europe, they evolve into the larger and stronger animal that is very similar to the horse as we know it today. For many years, the horse was probably hunted for food by early tribes of human beings. Then the qualities of the horse that would have made it a good servant were noted – mainly its strength and speed. It was time for the horse to be tamed, used as a draft animal at the dawning of agriculture, and than ridden as the need for transportation increased. It was the descendant of this domesticated horse that was brought back to the Americas by European colonists.
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