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Primate origin. K-T boundary. Primate Origins. Challenge is to minimize speculation on things that do not fossilize. We live in the Cenozoic Era (past 65 m.y.) Earliest primate fossils date from c. 63 mya; Eocene Epoch Originated from primate-like mammals. An Eocene mammal. An Eocene
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Primate origin K-T boundary
Primate Origins • Challenge is to minimize speculation on things that do not fossilize. • We live in the Cenozoic Era (past 65 m.y.) • Earliest primate fossils date from c. 63 mya; Eocene Epoch • Originated from primate-like mammals
An Eocene mammal An Eocene primate Post-orbital bar
Anthropoid Origins Aegyptopithecus Basal to the ape- Old World monkey separation ca. 33 mya
A transitional? group * • Genus Proconsul • Many species • Mixture of monkey-like and ape-like characteristics • 23 mya • Africa * the only extant tailless monkey is the ‘Barbary Ape.’
Adjusting branch-points an ongoing process e.g., fossil dated at 6-7 mya East Africa, Rift Valley system major hominid sites
Rocky Mountain News - July 11, 2002 Sahelanthropus tchadensis
Early Hominids • Ardipithecus ramidus (5.8 mya) • Australopithecus anamensis (4.2 mya) • basal to other australopithecines) • definitive evidence of bipedalism. • Derivative australopithecines divided into “gracile” and “robust” species groups
Genetic evidence for split
Australopithecus afarensis “Lucy” (Hadar, Ethiopia)
3.8 mya Australopithecus afarensis? Why?
Australopithecus afarensis (Hadar, Ethiopia). Most complete skull found to date Prognathism
Dental arcade = Diastema Parallel or slightly convergent Divergent C-shape Parallel
“Taung child” Australopithecus africanus 1925 South Africa Age at death?