Chapter 14 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 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 populations—more than 6 billion living humans—are placed within this species (and the same subspecies as well).

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?

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.

Modern Humans From Africa and the Near East

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.

Question 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.

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. a) the partial replacement model b) the regional continuity model c) the regional replacement model d) the complete replacement model

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.

Question 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.

Early Homo sapiens Discoveries From Africa and the Near East Site Dates (y.a.) Human RemainsComments Qafzeh (Israel) 110,00020 individuals (minimum) Large sample; variability in expression of modern traits Skhu-l (Israel) 115,00010 individuals (minimum) Earliest evidence of modern H. sapiens outside of Africa

Early Homo sapiens Discoveries From Africa and the Near East Site Dates (y.a.) Human RemainsComments Omo-Kibish (Ethiopia) 120,000– 80,000? 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

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

Herto Cranium From Ethiopia Herto cranium from Ethiopia, dated 160,000–154,000 ya. This is the best- preserved early modern H. sapiens cranium yet found.

Mt. Carmel Mt. Carmel, studded with caves, was home to H. sapiens sapiens at Skhu¯l (and to Neandertals at Tabun and Kebara).

Specimens from Israel (a) Skhu¯l 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.

Early Modern Homo sapiens Discoveries - Europe, Asia, Australia Site Dates (y.a.) Human RemainsComments Abrigo do Lagar 24,500 4 y.o. child’s 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

Early Modern Homo sapiens Discoveries - Europe, Asia, Australia Site Dates (y.a.) Human Remains Comments Ordos (Mongolia, China) 50,0001 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 3 individuals, one cremation Date is controversial; recent extraction and analysis of DNA

Anatomically Modern Homo sapiens (Asia and Australia).

Anatomically Modern Humans in Europe

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.

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

Timeline for Modern Homo Sapiens Discoveries

Techniques for Dating Middle and Upper Pleistocene Sites TechniquePhysical BasisExamples 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 Thermolumi nescence (TL) Accumulation of electrons in certain crystals released during heating Date ancient flint tools; provide key dates for the Qafzeh site

Techniques for Dating Middle and Upper Pleistocene Sites TechniquePhysical BasisExamples of Use Electron spin resonance (ESR) Measurement of trapped electrons Date dental enamel; corroborate dating various sites in Israel, Java, South Africa, and Australia

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

Location of the Flores Site in Indonesia

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 21,000 27,000 40,000 Magdalenian Solutrean Gravettian Aurignacian Chatelperronian Middle Paleolithic Mousterian

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.

The Punch Blade Technique (a) A large core is selected and the top portion is removed by use of a hammerstone.

The Punch Blade Technique (b) The objective is to create a flat surface called a striking platform.

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).

The Punch Blade Technique (d) Or the blades can be removed by pressure flaking.

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).

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

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