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Hominid Fossil Record

Hominid Record

Geology 230: and

Human ancestors

A.=Australopithicus

Collecting Hominid fossils in East Using Stratigraphy and Radiometric Dating to date hominid fossils A Hominid Jawbone in Hominid Record, 2002 tchadensis, 6.5 MY old Sahelanthropus tchadensis, 6.5 MY old – female on left, male on right; note the tugenensis – the sum total of specimens ramidus, 2009

Ardipithecus ramidus, 2009

Hand Foot Ardipithecus ramidus

Digitally Reconstructed Skull from Broken Pieces using Computed Tomography anamensis The

• Ardipithecus: oldest definite bipedal ancestor, over 4 M.Y. old • Australopithecus: the gracile australopithecines • : the robust australopithecines Fossil

• Ardipithecus ramidus: 4.4 MY, teeth, jaws and fragments suggest it is a hominid, not a pongid. • Australopithecus afarensis: 3.8-3.0 MY based on good fossils. Clearly a bipedal based on and fossil . Bipedal Footprints of Australopithecus in Lithified Volcanic Ash 4 MY old from . Found by .

Australopithecus couple making footprints in volcanic ash Jawbones of Australopithecus afarensis Fossil remains of “”, the most complete specimen of Australopithecus afarensis. An adult skull, A. afarensis of Australopithecus afarensis Reconstruction of Australopithecus afarensis Face-to-face with A. afarensis A troop of A. afarensis feeding on tubers in the forest. A. afarensis family unit crossing the savannah. Fossil Species

• Australopithecus africanus: 2.8-2.5 MY • Robust australopithecines: Paranthropus aethiopicus: 2.6-2.2 MY P. robustus: 2.0-1.2 MY P. boisei: 2.6-1.0 MY The Child, A. africanus Skull of Paranthropus boisei Paranthropus aethiopicus Paranthropus aethiopicus Justus Erus found the fossil

Kenyanthropus platyops, 3.5 MY old from rudolfensis or rudolfensis? Fossil Species

• : 2.5-1.6 MY • H. erectus: 1.8 MY- 25,000 yrs? • H. sapiens: archaic vs. modern Skull of Homo habilis H. rudolfensis, H. habilis, and P. boisei. Hominids in around 2 MY ago. *

Phylogeny 2000

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* * Poorly known * * *

Phylogeny * 2007 *

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* Poorly known * *

Prothero, 2007 2010

Skull of from Skeleton of Homo erectus, Nariokotome boy from Kenya H. erectus skull of Nariokotome boy The face of Homo erectus Homo erectus from Indonesia, Homo erectus using fire to sharpen Homo sapiens

• Archaic H. sapiens or unique species? H. antecessor: 800,000 old H. heidelbergensis: 500,000 years old H. neandertalensis: 200,000-32,000 years old from , 800,000 years old , 500,000 years BP skull, Spain Fleshing out a Neanderthal skull Neanderthal , 50,000 yrs. BP Neanderthal skeleton, Germany Homo neadertalensis leading a nomadic existence Neandertals were big-game hunters. Neandertal night life around the fire. A more modern view of Neandertals with naked skin like ours? Reconstruction of Neanderthal child from Gibraltar, Spain, 30,000 years B.P. Homo sapiens

• modern H. sapiens East Africa: 195,000 years ago Middle East: 90,000 years ago Australia: 50,000 years ago : 32,000 years ago Americas: 20,000 years ago Homo sapiens, , 90,000 yrs BP FYI: Abraham lived only 4,000 yrs BP Cro-Magnon man from France, 30,000 years old , a hobbit-size from Flores Island, Indonesia, 18,000 BP

Modern human Homo sapiens (Cro-Magnon people) drew the art in France and Spain about 17,000 years ago. , France, cave art

Life in the late , which ended at different times on different continents. The invention of farming, plus of , started civilization. Evolution of Modern

Two Theories: • Out of Africa: all modern humans descended from a single population. Racial differences have very recent origins. • Multiregional Theory: modern humans evolved from local populations of H. erectus at several places in the Old World. Accounts for the racial differences in modern humans. Multiregional vs Hypothesis Out of Africa Hypothesis Tree DNA studies Diagram show the of Genetic Similarity common ancestor of all humans lived in Africa about 170,000 yrs ago

How far back in time did the modern “races” diverge from a common ancestor? Maybe 50-100 Ka

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