Chapter Study Outline

  1. What Is So Modern about Modern Humans?
    1. Skeletal traits: round, tall skull with vertical forehead, small brow ridges, and small face and teeth with a more gracile postcranial skeleton characteristic of modern humans.
    2. Some hominid skeletons have a mixture of archaic and modern traits, such as Skhul 5 and Herto hominids.
  2. Modern Homo sapiens: Single Origin and Global Dispersal or Regional Continuity?
    1. Evolution of modern humans began about 350,000 yBP with emergence of archaic forms.
    2. First modern Homo sapiens appeared in Africa, 200,000 yBP.
    3. Two main hypotheses
      1. Out of Africa—Modern Homo sapiens evolved in Africa, and then spread to Asia and Europe, where modern humans replaced the populations there.
      2. Multiregional Continuity—The shift to modern humans took place regionally and did not involve replacement.
  3. What Do Homo sapiens Fossils Tell Us about Modern Human Origins?
    1. Early Archaic Homo sapiens
      1. Evolved out of earlier Homo erectus populations
      2. Reduced skeletal robusticity, smaller tooth size, expansion in brain size, increasing cultural complexity
      3. Archaic Homo sapiens in Africa (350,000–200,000 yBP)
        1. Enormous brow ridges, but gracile facial bones; large brain
      4. Early Archaic Homo sapiens in Asia (350,000–130,000 yBP)
        1. Ngandong (Java) has some of the best-known fossils (braincases) with a high skulls
      5. Early Archaic Homo sapiens in Europe (500,000–130,000 yBP)
        1. Sima de los Huesos site yielded Atapuerca 5, a well-preserved skeleton, with a large brain and pronounced facial projection.
      6. Early Archaic Homo sapiens’ Dietary Adaptations
        1. Same tools and material technology as Homo erectus but diverse materials
        2. Reduction of dental complex with tool use
    2. Late Archaic Homo sapiens
      1. Late Archaic Homo sapiens in Asia (60,000–40,000 yBP)
        1. Neandertals found in Amud, Kebara, and Tabun
        2. Shanidar site best known; several individuals with interesting life histories seen in their skeletons
        3. Amud Neandertal has the largest hominid brain size ever found (1,740 cc).
        4. Characterized by small, round eye orbits, large and wide nasal openings, and projecting faces
        5. Lack the occipital bun and large teeth of earlier Homo species
      2. Late Archaic Homo sapiens in Europe (130,000–30,000 yBP)
        1. Earliest are the Krapina Neandertals from Croatia
          1. Distinctive cut marks on bones suggest possible cannibalism
      3. The Neandertal Body Plan: Aberrant or Adapted?
        1. La Chapelle-aux-Saints studied first by Boule
          1. Boule influenced thinking about the Neandertals.
          2. Thought Neandertals had bent-kneed gait
          3. Thought Neandertals were primitive and stupid
        2. Cold adaptation of Neandertals
          1. Large nasal aperture
          2. Large infraorbital foramina
          3. Stocky build, short limbs
      4. Neandertal Hunting: Inefficient or Successful?
        1. Established Mousterian (Middle Paleolithic) tool tradition and participated in the Upper Paleolithic tool traditions
        2. Butchered animal bones found
        3. Animals processed for food
        4. Chemical evidence indicates importance of meat in diet.
      5. Neandertals Buried Their Dead
        1. European, western Asian sites indicate burial; others do not.
        2. Spy, La Chapelle-aux-Saints, Amud, Tabun, also individuals from Shanidar
      6. Neandertals Talked
        1. Some argue Neandertals could not produce range of sound necessary for language.
        2. Evidence is mounting for Neandertals’ ability to speak.
          1. Kebara hyoid bone
          2. Reconstruction of vocal tract
          3. Wear patterns on teeth
      7. Neandertals Used Symbols
        1. Painted shells dating to 50,000 yBP from Spain suggest ornamentation and therefore symbolism.
    3. Early Modern Homo sapiens
      1. Early Modern Homo sapiens in Africa (200,000–6,000 yBP)
        1. Herto, Aduma, Awash Valley, Omo
        2. Cranial capacity anatomically close to modern humans’
        3. Relatively tall cranium, vertical forehead, smaller brow ridges, nonprojecting face
        4. Relatively long face and brow ridge are archaic features
        5. Skull from Klasies River Mouth Cave in Africa has a modern chin
      2. Early Modern Homo sapiens in Asia (90,000–18,000 yBP)
        1. Skhul, Tianyuan Cave, Zhoukoudian
        2. Retain thick cranial bones and large brow ridges
        3. Facial flatness characteristic of modern eastern Asians
      3. Early Modern Homo sapiens in Europe (35,000–15,000 yBP)
        1. Oase, Predmostí, Dolni Vestnice
        2. Many skulls show mixture of Neandertal and modern characteristics.
        3. Some Neandertal facial features persist into recent times in eastern Europe.
        4. Trends toward gracilization—faces, jaws, teeth became smaller and faces became less projecting
    4. Modern Behavioral and Cultural Transitions Happened First in Africa
      1. Painting, hunting, fishing, tool production, jewelry
      2. It was once thought that these originated in Europe.
      3. At Katanda (Congo), catfish remains found from as early as 75,000 yBP suggest exploitation as a food source by Homo sapiens.
  4. How Has the Biological Variation in Fossil Homo sapiens Been Interpreted?
    1. Fossil Record
      1. Overlap in dates between Neandertals and early modern humans indicates coexistence, which goes against regional continuity model
      2. Earliest modern Homo sapiens had clear Neandertal features, suggesting gene flow, which argues against the Out of Africa model.
    2. Ancient DNA: Interbreeding between Neandertals and Early Modern People?
      1. Eurasians and Neandertals share between 1%–4% of nuclear DNA.
      2. This is a small but significant admixture.
      3. Africans share no nuclear DNA with Neandertals, however.
      4. People living outside of Africa have DNA that likely originated from Neandertals.
    3. Living People’s Genetic Record: Settling the Debate on Modern Humans’ Origins
      1. Genetic diversity in Africa suggests modern people have existed longer there than in Asia or Europe (Cann and colleagues).
      2. Genetic diversity in Africa and lack thereof in Asia and Europe could be the result of genetic drift, not necessarily antiquity of the population (Relethford).
  5. Assimilation Model for Modern Human Variation: Neandertals Are Still with Us
    1. Discordance in the fossil and genetic records suggests that current models do not adequately explain modern human origins.
    2. Neandertals contributed to modern gene pool in Europe and Asia.
  6. Modern Humans’ Other Migrations: Colonization of Australia, the Pacific, and the Americas
    1. Initial spread of population out of Africa, into Asia and Europe
    2. Spread to other parts of the world in the last 50,000 years—first Australia and then to the Americas
    3. Down Under and Beyond: The Australian and Pacific Migrations
      1. Lake Mungo remains date to 40,000 yBP, oldest in Australia
      2. Bear strong resemblance to modern native Australians
      3. Many parts of southeast Asia not settled until 5,000 yBP
      4. Flores remains (the so-called hobbit) at 18,000 yBP challenge the conclusions about the evolution of humans in far eastern Asia
    4. Arrival in the Western Hemisphere: The First Americans
      1. Shovel-shaped incisors first clue that Native Americans are related to East Asians
      2. Americas possibly settled by a single population, starting around 15,000 yBP
      3. Paleoindians hunted megafauna
      4. Some skull differences between Paleoindians and modern Native Americans, but this likely reflects changes in the use of the face and jaws over 10,000 years