Chapter 11 Homo sapiens sapiens by lm0N43u

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									     Chapter 11
       The Origin and
Dispersal of Modern Humans
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
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.”
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?
Theories of Human Origins
   Complete Replacement Model
   Regional Continuity Model
   Partial Replacement Model
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.
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.
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.
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.
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.
Early Homo sapiens Discoveries
From Africa and the Near East
           Dates        Human
 Site                                     Comments
           (y.a.)      Remains
Qafzeh     110,000   20 individuals     Large sample;
(Israel)              (minimum)          variability in
                                        expression of
                                        modern traits
Skhu-l     115,000   10 individuals   Earliest evidence of
(Israel)              (minimum)       modern H. sapiens
                                       outside of Africa
Early Homo sapiens Discoveries
From Africa and the Near East
               Dates      Human
   Site        (y.a.)    Remains         Comments
                          Cranium
                                       Second individual
Omo-Kibish    120,000–      and
                                         shows fewer
 (Ethiopia)   80,000?    postcranial
                                         modern traits
                          remains
  Klasies
                          Several      Perhaps earliest
River Mouth
              120,000? individuals;      modern H.
   (South
                       fragmentary     sapiens in Africa
   Africa)
Early Modern Homo sapiens
Discoveries - Europe, Asia, Australia
             Dates     Human
  Site       (y.a.)   Remains             Comments
                        4 y.o.
Abrigo do
             24,500    child’s      Shows mixture of traits
 Lagar
                      skeleton
  Velho                             Interpreted as evidence
(Portugal)                               of hybridization
                                      Famous site of early
  Cro-
                           8          modern H. sapiens;
Magnon       30,000
                      individuals   variability in expression
(France)
                                        of modern traits
Early Modern Homo sapiens
Discoveries - Europe, Asia, Australia
             Dates      Human
   Site                                 Comments
             (y.a.)    Remains
  Ordos                               Perhaps earliest
(Mongolia,   50,000   1 individual     evidence of H.
  China)                              sapiens in Asia
  Kow               More than 40
            14,000-                      Very robust
 Swamp               individuals
             9,000                       individuals
(Australia)           (all ages)
  Lake
                    3 individuals, Date is controversial;
 Mungo      60,000-
                         one       recent extraction and
(Australia) 30,000
                     cremation       analysis of DNA
Techniques for Dating Middle
and Upper Pleistocene Sites
Technique         Physical Basis             Examples of Use
                                       Date limestone formations;
                Radioactive decay of
  Uranium                            estimate age of Jinniushan site
                 short-lived uranium
   series                            in China and Ngandong site in
                      isotopes
                                                  Java
                 Accumulation of
Thermolumin     electrons in certain   Date ancient flint tools; provide
escence (TL)     crystals released      key dates for the Qafzeh site
                  during heating
Electron spin                                Date dental enamel;
 resonance        Measurement of       corroborate dating various sites
   (ESR)         trapped electrons      in Israel, Java, South Africa,
                                                 and Australia
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.
Anatomically modern Homo
sapiens and Homo floresiensis
The Upper Paleolithic
   Cultural period began in western Europe
    approximately 40,000 years ago.
   Industries based on tool technologies:
    1. Chatelperronian
    2. Aurignacian
    3. Gravettian
    4. Solutrean
    5. Magdalenian
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.
Cultural Periods of the
European Upper Paleolithic
 Upper Paleolithic
   (beginnings)        Cultural Periods

      17,000         Magdalenian Solutrean
      21,000              Gravettian
      27,000             Aurignacian
      40,000           Chatelperronian

     Middle
    Paleolithic           Mousterian
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.
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.
Quick Quiz
1. Which of the following is NOT one of the
    hypotheses explaining the origins and
    dispersal of anatomically modern
    humans?
   a) the partial replacement model

   b) the regional continuity model

   c) the regional replacement model

   d) the complete replacement model
Answer: c
   The regional replacement model is
    NOT one of the hypotheses explaining
    the origins and dispersal of anatomically
    modern humans.
2. Scientists are fairly clear on when
  anatomically modern Homo sapiens first
  appeared.
    True

    False
Answer: False
   Scientists are not fairly clear on when
    anatomically modern Homo sapiens first
    appeared.
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.
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.
4. The model also known as "Recent
    African Evolution" is based on the origin
    of modern humans
   a) in Africa and their interbreeding with
       local African populations.
   b) in Africa and their replacement of local
       populations in Europe and Asia.
   c) in China and their relatively recent
       evolution in Africa.
   d) simultaneously in Africa and China.
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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