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The Evolution of a Horse Essay

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The Evolution of a Horse Throughout history, humans have depended on the horse. Horses have contributed to the growth of humankind as transportation, farm workers, and battle steeds. They have been trained to support humans in many ways. When did this relationship begin? At what point did the horse become a vital part of human society? Exploring the evolution of the horse can help to answer these questions. A mammal with hooves that have an odd number of toes on the rear feet are known as odd-toed ungulates. The middle toe on each rear hoof is usually larger than the ones next to them. Horses are members of the odd-toed ungulates which includes the horses, tapirs, and rhinoceroses. They are relatively large grazing animals with …show more content…

Four of the toes had early proto-hooves. The back legs had small hooves on three of the five toes. The toes were padded like a dog’s toes. The Hyracotherium had three incisors, one canine, four premolars, and three grinding molars on each jaw, which was a typical tooth structure of early mammals who were omnivorous browsers (Hunt 4). Eohippus survived for about twenty million years with relatively few evolutionary changes (Wikipedia 7). These animals lived in a sub-tropical climate and ate soft fruits and the leaves of trees.
During the middle to late Eocene and into the Oligocene epoch several other members of the equids, with distinct evolutionary changes, existed including the Orohippus, Epihippus, Mesohippus, and Miohippus. The Orohippus developed from the Hyracotherium and shared many of the same traits. One major change was that the first and second toes disappeared. Another significant change occurred in the teeth. The last premolar changed to become like a grinding molar. Also the crests were more defined showing that the Orohippus’s diet had changed to a tougher plant material. During the middle Eocene a descendant of Orohippus appeared. The Epihippus still resembled a dog-like animal. It had four padded toes on the front leg, and three on the back leg. However, the teeth changed more drastically with two of the premolars changing to grinding molars. Now there were five grinding cheek teeth with low crowns. As

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