The Origin and Dispersal of Modern Humans

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Chapter 14

• The Origin and Dispersal of Modern Humans

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Chapter Outline

• Approaches to Understanding Modern Human Origins
• The Earliest Discoveries of Modern Humans
• Something New and Different
• Technology and Art in the Upper Paleolithic
• Summary of Upper Paleolithic Culture

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Homo sapiens

• Sometime, probably close to 200,000 years ago,
  the first modern Homo sapiens evolved in Africa.
• Within 150,000 years or so, their descendants had
  spread across most of the Old World, even
  expanding as far as Australia.
• All contemporary populationsmore than 6 billion
  living humansare placed within this species
  (and the same subspecies as well).

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Questions About the Origin and Dispersal of
Modern Humans

• When did modern humans first appear?
• Where did the transition take place?
• In one region or several?
• What was the pace of evolutionary change?
• How fast did the transition occur?
• How did the dispersal of modern humans to other
  areas of the Old World take place?

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Theories of Human Origins

• Complete Replacement Model
• Regional Continuity Model
• Partial Replacement Model

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Complete Replacement Model (Recent African
Evolution)

• Developed by British paleoanthropologists
  Christopher Stringer and Peter Andrews.
• Proposes anatomically modern populations arose in
  Africa in the last 200,000 years.
• They migrated from Africa, completely replacing
  populations in Europe and Asia.
• Does not account for the transition from archaic
  H. sapiens to modern H. sapiens anywhere except
  Africa.

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Modern Humans From Africa and the Near East
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Partial Replacement Model

• Proposed by Günter Bräuer of the University of
  Hamburg.
• Postulates the earliest dates for African modern
  Homo sapiens at over 100,000 y.a.

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Partial Replacement Model

• Initial dispersal of H. sapiens sapiens from
  South Africa was influenced by environmental
  conditions.
• Moving into Eurasia, modern humans hybridized
  with resident groups, eventually replacing them.
• The disappearance of archaic humans was due to
  hybridization and replacement.

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Regional Continuity Model(Multiregional
Evolution)

• Associated with paleoanthropologist Milford
  Wolpoff of the University of Michigan.
• Populations in Europe, Asia, and Africa continued
  evolutionary development from archaic H. sapiens
  to anatomically modern humans.

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The Regional Continuity Model(Multiregional
Evolution)

• Question How did modern humans evolve in
  different continents and end up so physically and
  genetically similar?
• Explanation
• Due to gene flow between archaic populations,
  modern humans are not a separate species.
• Earlier modern H. sapiens did not originate
  exclusively in Africa.

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Question

• Which of the following is not one of the
  hypotheses explaining the origins and dispersal
  of anatomically modern humans?
• the partial replacement model
• the regional continuity model
• the regional replacement model
• the complete replacement model

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Answer c

• The regional replacement model is not one of the
  hypotheses explaining the origins and dispersal
  of anatomically modern humans.

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Question

• Which hypotheses holds that anatomically modern
  populations arose in Africa within the last
  200,000 years, migrated out and replaced
  populations in Europe and Asia. They did not
  interbreed, they were a separate species.
• the partial replacement model
• the regional continuity model
• the regional replacement model
• the complete replacement model

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Answer c

• The Complete Replacement Model holds that
  anatomically modern populations arose in Africa
  within the last 200,000 years, migrated out and
  replaced populations in Europe and Asia. They did
  not interbreed, they were a separate species.

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Question

• The model also known as "Recent African
  Evolution" is based on the origin of modern
  humans
• in Africa and their interbreeding with local
  African populations.
• in Africa and their replacement of local
  populations in Europe and Asia.
• in China and their relatively recent evolution in
  Africa.
• simultaneously in Africa and China.

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Answer b

• The model also known as "Recent African
  Evolution" is based on the origin of modern
  humans in Africa and their replacement of local
  populations in Europe and Asia.

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Early Homo sapiens Discoveries From Africa and
the Near East
Site Dates (y.a.) Human Remains Comments
Qafzeh(Israel) 110,000 20 individuals (minimum) Large sample variability in expression of modern traits
Skhu-l (Israel) 115,000 10 individuals (minimum) Earliest evidence of modern H. sapiens outside of Africa
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Early Homo sapiens Discoveries From Africa and
the Near East
Site Dates (y.a.) Human Remains Comments
Omo-Kibish (Ethiopia) 120,00080,000? Cranium and postcranial remains Second individual shows fewer modern traits
Klasies River Mouth (South Africa) 120,000? Several individuals fragmentary Perhaps earliest modern H. sapiens in Africa
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Omo I

• Reconstructed skull of Omo I, an early modern
  human from Ethiopia, dated to 195 kya.
• Note the clear presence of a chin.

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Herto Cranium From Ethiopia

• Herto cranium from Ethiopia, dated
  160,000154,000 ya.
• This is the best- preserved early modern H.
  sapiens cranium yet found.

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Mt. Carmel

• Mt. Carmel, studded with caves, was home to H.
  sapiens sapiens at Skhul (and to Neandertals at
  Tabun and Kebara).

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Specimens from Israel

• (a) Skhul 5. (b) Qafzeh 6.
• These specimens from Israel are thought to be
  representatives of early modern Homo sapiens.
• The vault height, forehead, and lack of
  prognathism are modern traits.

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Early Modern Homo sapiens Discoveries - Europe,
Asia, Australia
Site Dates (y.a.) Human Remains Comments
Abrigo do Lagar 24,500 4 y.o. childs skeleton Shows mixture of traits
Velho (Portugal) Interpreted as evidence of hybridization
Cro-Magnon (France) 30,000 8 individuals Famous site of early modern H. sapiens variability in expression of modern traits
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Early Modern Homo sapiens Discoveries - Europe,
Asia, Australia
Site Dates (y.a.) Human Remains Comments
Ordos (Mongolia, China) 50,000 1 individual Perhaps earliest evidence of H. sapiens in Asia
Kow Swamp (Australia) 14,000-9,000 More than 40 individuals(all ages) Very robust individuals
Lake Mungo (Australia) 60,000- 30,000 3 individuals, one cremation Date is controversial recent extraction and analysis of DNA
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Anatomically Modern Homosapiens (Asia and
Australia).
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Anatomically Modern Humans in Europe
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Early Modern Homo Sapiens in Central Europe

• The Mlade c (a) and Dolní V estonice (b) crania,
  from the Czech Republic, are good examples of
  early modern Homo sapiens in central Europe.

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Cro-Magnon I

• Cro-Magnon I (France).
• In this specimen, modern traits are quite clear.
  (a) Lateral view. (b) Frontal view.

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Timeline for Modern Homo Sapiens Discoveries
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Techniques for Dating Middle and Upper
Pleistocene Sites
Technique Physical Basis Examples of Use
Uranium series Radioactive decay of short-lived uranium isotopes Date limestone formations estimate age of Jinniushan site in China and Ngandong site in Java
Thermoluminescence (TL) Accumulation of electrons in certain crystals released during heating Date ancient flint tools provide key dates for the Qafzeh site
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Techniques for Dating Middle and Upper
Pleistocene Sites
Technique Physical Basis Examples of Use
Electron spin resonance (ESR) Measurement of trapped electrons Date dental enamel corroborate dating various sites in Israel, Java, South Africa, and Australia
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Flores Hominids

• Cranium of adult female Homo floresiensis from
  Flores, Indonesia, dated 18,000 ya.

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Location of the Flores Site in Indonesia
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The New World

• Ancestors of Native Americans reached the New
  World through migration over the Bering Land
  Bridge over many millennia.
• Debates continue, but at present, the only direct
  evidence of hominids in the New World date to
  about 12,000 y.a.

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Anatomically modern Homo sapiens and Homo
floresiensis
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The Upper Paleolithic

• Cultural period began in western Europe
  approximately 40,000 years ago.
• Industries based on tool technologies
• Chatelperronian
• Aurignacian
• Gravettian
• Solutrean
• Magdalenian

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Upper Paleolithic Tools

• (a) Burin. A very common Upper Paleolithic tool.
• (b) Solutrean blade. This is the best-known work
  of the Solutrean tradition.
• Solutrean stonework is considered the most highly
  developed of any Upper Paleolithic industry.

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Cultural Periods of the European Upper Paleolithic
Upper Paleolithic (beginnings) Cultural Periods
17,000 21,000 27,000 40,000 Magdalenian SolutreanGravettian Aurignacian Chatelperronian
Middle Paleolithic Mousterian
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Upper Paleolithic Grave

• Skeleton of two teenagers, a male and a female,
  from Sungir, Russia.
• Dated 24,000 ya, this is the richest find of any
  Upper Paleolithic grave.

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The Punch Blade Technique

• (a) A large core is selected and the top portion
  is removed by use of a hammerstone.

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The Punch Blade Technique

• (b) The objective is to create a flat surface
  called a striking platform.

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The Punch Blade Technique

• (c) Next, the core is struck by use of a hammer
  and punch (made of bone or antler) to remove the
  long narrow flakes (called blades).

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The Punch Blade Technique

• (d) Or the blades can be removed by pressure
  flaking.

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The Punch Blade Technique

• (e) The result is the production of highly
  consistent sharp blades, which can be used, as
  is, as knives or they can be further modified
  (retouched) to make a variety of other tools
  (such as burins, scrapers, and awls).

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Magdalenian Bone Artifact

• Note the realistic animal engraving on this
  object, the precise function of which is unknown.

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Artifacts from the Middle Stone Age of Africa and
the Upper Paleolithic in Europe