Early Hominids. Early Hominids. Early Hominids. Plio-Pleistocene 5-1 mya Considerable worldwide faunal changes. N Hominiod. N Hominid.

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1 Ardipithecus ramidus Robust Australopithecines: robustus boisei aethiopicus africanus Early Hominids N Hominiod Superfamily Hominoidea [gibbons, great apes, us] 2:1:2:3 dental formula diurnal afarensis anamensis Large brains relative to other primates No tails Suite of characteristics associated with suspensory adaption Early Hominids Early Hominids N Hominid N Human Expanded brains Bipeds Simple tool manufacture Opportunistic hunting Beginning of complex social learning Small short face Extremely opposable thumb Lack of body hair Ardipithecus (?) to us Reduced sexual dimorphism Habitually bipedal Complex and conceptual toolmaking Organized big-game hunting Complex social behavior/culture Grossly large brain language??? to us Ardipithecus ramidus White & Clarke, Aramis, Ethiopia, in thickly wooded habitat 17 fossils - bipedal More primitive than A.afarensis Plio-Pleistocene 5-1 mya Considerable worldwide faunal changes Dated at 4.4 my BP First named, but changed to Ardipithecus

2 Genus anamesis southern ape of Africa from southern and east Africa first undeniable hominids brain size near that of apes no evidence of speech shows efficient bipedalism Maeve Leakey & NM Kenya Discovered in 1994 Kanapoi - SW Lake Turkana Allia Bay - NE end of lake ~ mya A. anamesis Mandible more primitive than Lucy, more like Miocene apes Post-cranial skeleton more advanced, more Homo like Teeth, elbow, jaws, lower legs East, central and south Africa Relative vs absolute dating techniques Robust and gracile species Genus/species designations afarensis

3 N Hadar Afar -- Lucy Ethiopia -- Afar triangle Donald Johanson mya N Laetoli Footprints Tanzania Mary Leaky, 1974 ~ 3.5 mya A. afarensis Laetoli Hadar N First Family Hadar Afar region, 1984 Portions of 13 individuals Dental Arcade & Teeth gorilla Lucy us Knee Joint Phalanges adducted longer condyle Pelvis short, broad small gluteals moved laterally increased angle to knee efficient biped Laetoli Footprints

4 Reconstructions First Family D. Johanson et al. 13 individuals flash flood age profile sexual dimorphism group structure?? N Taung child ß Raymond Dart ß Face & endocast africanus N Sterkfontein ß Robert Broom ß over 600 specimens Taung Son of Lucy stratigraphy breccia osteodontokeratic tool industry apology in Nature N Makapansgat ß Raymond Dart, 1947 ß Nearly complete skull and pelvis mya Reasons for dismissal People believed the site of human evolution was Asia Published in same year as Scopes trial Small brain size People believe a suite of traits evolved together: Bipedalism Large brains Manipulative hands tool use language africanus

5 South African Stratigraphy Cave sites, hard to date Accumulation at base of cavern robustus N Kromdraii ß Robert Broom, 1937 ß Paranthropus robustus N Swartkrans ß Robert Broom, 1937 ß robustus Olduvai A. robustus Swartkrans Kromdraii ~2-1 mya bosei N Olduvai Gorge N Peninj N Lake Turkana Predator & Prey ß Robert Brain ß carnivore tooth marks ß part of prey midden ß East Africa ß Leakey family ß First believed to be the makers of stone tools found nearby at Oduvai Gorge ß chewing machine ~2.4-1 mya

6 Olduvai boisei Mary Leakey finds hyper-robust skull Zinjanthropus boisei -- Zinj boisei ~1.8 mya Very dimorphic boisei aethiopicus N Black Skull Lake Turkana Walker & Leakey, 1986 Hyper-robust form Long snout & cranium like afarensis Broad face like boisei Ancestor to boisei? Olduvai ~2.6 mya Swartkrans Kromdraii A. aethiopicus [Black Skull; WT 17] 6-7 my BP Thought to be close to the divergence of apes and hominids Sahelanthropus tchadensis

7 Robust Australopithecines: Ardipithecus ramidus robustus boisei aethiopicus africanus afarensis anamensis