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The Cenozoic Era (65mya-now)
- - Paleocene epoch began 65 mya
- - Eocene epoch began 54 mya
- - Oligocene epoch began 34 mya
- - Miocene epoch began 23 mya
- - Pliocene epoch began 5 mya- Pleistocene epoch began 2 mya
- Holocene epoch began 12,000 ya
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Paleocene epoch (65 mya):
primate like
- Plesiadapiformes (plesiadapids)
- - small primate like animals from the late paleocene once thought to be primates.
- - but they only share ancestral traits w/primates.
- - no post orbital bar.
- ..technically not primates
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Eocene epoch (54 mya)
first true primates
- - The Eocene was the Age of the Primates
- - impressie adaptive radiation of primates
- - related to the emergence of flowering plants(angiosperms) and insects
- - Pleisiadapids, Adapids, Omomyids
- (not primates) (lemur/loris) (tarsier-like)
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Oligocene epoch (54 mya)
the earliest anthropoids
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Continental drift and the South American primate problem
- Maybe they came from N. America?
- -No anthropoid fossils found in N. America
- -Morphological data suggest that S. American primates came from Africa
- -S. America and Africa were seperated by 2000mi
- -Vegetation rafts from mangroves?
- -Maybe anthropoid primates actually appeared in Africa much sooner than we think
- -Africa and S.America would have been closer to each other further back in time(not so far to float)
- -the oldest anthropoid fossil we have managed to find is probably not the oldest member of the anthropoid lineage
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Aegyptopithecus
found in the Fayum by Elwyn Simons
- Definition is clearly Anthropoid like:
- - low rounded cusps
- - 5 cusps on the lower molars (Y-5)
- - 2 premolars (like all catarrhines)
- BUT retains some ancestral traits:
- - long snout
- - small brain case
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Aegyptopithecus is...
close to the root of all catarrhines
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Miocene epoch (23 mya)
early hominoids
- Proconsul
- - some think Procunsul might be a direct ancestor of the African apes.
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Proconsul lacked...
- -the brachiating complex of all living hominoids
- -a tail
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Proconsul emerged...
- somewehre near the root of modern Hominoids
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ASIAN LINEAGE: Sivapithecus (12-18mya)
Probable ancestor of the orangutans
- - narrow interotbits
- - ovoid orbits
- - no brow ridges
- - no frontal sinus
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Gigantopithecus
- another Asian ape is similar to an over-sized Sivapithecus
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it had enormous jaws and molars
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Hypothesis for the evolution of bipedalism
- 1. efficient locomotion between dispersed food resources
- 2. thermoregulation
- 3. frees hands to carry useful items
- 4. permits efficient harvest from small fruit trees
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