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6 Cards in this Set
- Front
- Back
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Pre Horse
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-75 million years ago -5 toed -size of small dog (rabbit) -NO fossils found |
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Eohippus (Dawn Horse)
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-50-60 million years ago -first fossils were found 12-14" tall w/arched back (rabbit back) -4 toes in front / 3 toes behind -lived in swamps/tropical forest -not herd living -low crown teeth (small for browsing) aka: Browsers |
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Mesohippus (Middle Horse)
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-35-38 million years ago -18-24" tall -3 toes in front & back -eye placement is more lateral (side of skull) -low crown teeth -fossils found only in North America |
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Merychippus (Rudimentary Horse)
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-20-28 million years ago -40" tall -longer legs, neck & straighter back -3 toes but only middle touches ground (other 2 --> current splint bones) -high crown teeth (large for grazing) -adapted to life on prairie -lives in herds aka: Grazers |
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Pliohippus
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-5-12 million years ago -50" tall -first one-toed horse (monodactyl) (made for speed on dry land) -muscle became bunched on upper leg (increases leverage/stride length) -traveled in herds -extensive migration -many types developed |
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Equus (modern day horse)
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-1 million years ago -originated in North America -size ranged from pony to draft size -1 toed -high crown teeth (grazing) -disappeared in North America about 12,000 years ago -no TRUE wild horses in North America *not able to migrate/inhabit Australia & Antarctica* |
