The Origin and Dispersal of Modern Humans

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Chapter 11

• 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 sapiens

• All contemporary populations are placed in the
  subspecies Homo sapiens sapiens.
• Most paleoanthropologists agree that several
  fossil forms, dating as far back as 100,000 y.a.,
  should be included in the same subspecies.
• Recently discovered fossils from Africa are
  clearly H. sapiens, but show minor differences
  from living people and could be described as
  near-modern.

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Questions About the Origin and Dispersal of H.
sapiens sapiens

• When did H. sapiens sapiens 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 H. sapiens sapiens 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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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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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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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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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
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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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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Cave Art

• Majority from southwestern France and northern
  Spain.
• Grotte Chauvet
• Dating has placed the cave painting during the
  Aurignacian period more than 30,000 y.a.
• Images include stylized dots, human handprints
  and animal representations.
• Among traces are dozens of footprints on the cave
  floor produced by bears and humans.

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Africa

• Rock art is found in southern Africa dating to
  between 28,000 and 19,000 y.a.
• Personal adornment dates back to 38,000 y.a. in
  the form of beads made from ostrich shells.
• Excavations in the Katanda area show remarkable
  bone craftsmanship.
• Intricate bone tools resembling harpoons were
  made from the ribs of large mammals.

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Quick Quiz
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• 1. 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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• 2. Scientists are fairly clear on when
  anatomically modern Homo sapiens first appeared.
• True
• False

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Answer False

• Scientists are not fairly clear on when
  anatomically modern Homo sapiens first appeared.

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• 3. The _________________ 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 because they were a separate
  species.

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Answer Complete Replacement Model

• 3. 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 because they were a separate
  species.

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• 4. 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.