The Origin and Dispersal of Modern Humans Chapter 11 The Origin and Dispersal of Modern Humans

Homo sapiens H. sapiens All contemporary hominin populations Vertical Foreheads Pyramidal mastoid process Point of attachment for several muscles Canine fossa Depression on the outer surface that allows for greater muscle control in non-verbal communication

Questions About the Origin and Dispersal of Modern Humans When (approximately) did modern humans first appear? Where did the transition take place? What was the pace of evolutionary change? How quickly did the transition occur? How did the dispersal of modern humans to other areas of the Old World (outside of their area of origin) take place?

Homo sapiens Most paleoanthropologists agree that fossil forms dating back as far as 100,000 ya should be included in the same fully modern group as modern humans Models of Human Origins: Multiregional Evolution “Out-of-Africa” Models

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

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

Partial Replacement Model Various perspectives suggest that modern humans originated in Africa and then, when their population increased, expanded out of Africa into other areas of the Old World This model claims that interbreeding occurred between emigrating Africans and resident premodern populations

Class Activity: Evaluating the Models Discuss three types of evidence Morphology in time and space Genetics Archaeological What patterns do you think would support each of the three models just profiled? In this activity, ask the class to think of the kind of data they would expect that would support the various models.

Time Line of Modern Homo Sapiens Discoveries: What do the Data Say?

Early Homo sapiens Discoveries From Africa and the Near East Dates Site Hominind Evolutionary Significance 195,000 ya Omo Ethiopia H. sapiens Oldest modern human; two crania found, one more modern looking than the other 154,000 - 160,000 ya Herto Ethiopia idaltu Well-preserved cranium; best-preserved early modern human found anywhere

Early Homo sapiens Discoveries From Africa and the Near East Dates Site Hominin Evolutionary Significance 115,000 ya Skhul Israel H. sapiens sapiens Minimum of 10 individuals; earliest modern humans known outside of Africa 110,000 ya Qafzeh Israel Large sample; modern, but some individuals fairly robust; early date

Herto Cranium Herto cranium from Ethiopia, dated 160,000–154,000 ya. Adult Mosaic of modern and premodern traits Very large and long cranial vault 1450 cm3 Large, arching browridge and projecting occipital protuberance H. sapiens idaltu “idaltu” is the Afar word for “elder”

Specimens From Israel Skhül 5. (a) 130,000-100,000 ya Qafzeh 6 (b) Modern traits Vault height Forehead Lack of prognathism Contemporary with Neandertals in Region

Key Early Modern Homo sapiens from Europe and Asia Dates Site Hominin Evolutionary Significance 40,000 ya Tianyuan Cave Beijing, China H. sapiens sapiens Partial skull and a few postcranial bones; oldest modern human find from China 40,000-45,000 ya Niah Cave Borneo, Indonesia Partial skull; oldest modern human find from Asia

Key Early Modern Homo sapiens from Europe and Asia Dates Site Hominin Evolutionary Significance 30,000 ya Cro-Magnon France H. sapiens sapiens Most famous early modern human find; earliest evidence of modern humans in France 24,500 ya Abrigo do Lagar Velho Portugal Child’s skeleton; possible hybrid of Neandertal and modern human, it is controversial

Geography of Modern Humans in East Asia and Australia

Australia 50,000 ya modern humans inhabited Sahul Area including New Guinea and Australia Lake Mungo, SE Australia 30,000-25,000 ya Kow Swamp 14,000-9,000 ya Fossils with archaic features Receding foreheads Heavy supraorbital tori Browridge Thick bones

Geography of Modern Humans in Europe

Mladec and Dolní Crania The Mladec (a) and Dolní Věstonice (b) crania from the Czech Republic Good examples of early modern Homo sapiens in central Europe Along with Oase in Romania, the evidence for early modern H. sapiens appears first in central Europe, then later in western Europe

Cro-Magnon I Cro-Magnon I (France) European Upper Paleolithic Approx 40,000 ya Modern traits are clear Robustly built and powerful Cranial capacity around 1,600 cc (a) Lateral view, (b) Frontal view

Neandertal/H. sapiens Admixture Abrigo do Lagar Velho “hybrid” child Recent Genetic comparisons of Neandertal DNA and contemporary humans Populations outside of Africa typically have more Neandertal DNA Refutes hypotheses of complete replacement of the Neanderthals by early modern humans

Comparing Skulls Homo Sapiens Neandertals The next few slides could contain images of Neandertal skulls paired with the ones profiled in Chapter 11. The goal could be to get students to identify those traits that are criteria for identification as H. sapiens. Not only would this reinforce taxonomic distinctions, but would also illustrate the continuous nature of morphological variation and that lines between species, especially fossil ones are blurry.

Homo floresiensis Indonesian island of Flores in 2004 Originally dated to 95,000 to 13,000 years ago New estimates until 50,000 years ago Archaic Homo survived much longer than expected Well into the lifespan of AMH Taxonomy Skull slightly smaller than chimpanzees Stood 3 feet tall Probably could not run Big feet, stubby big toe History H. erectus arrives in Flores 840,000 years ago Controlled fire and used stone tools more sophisticated than H. erectus Influenced by same evolutionary forces that led to smaller species of elephant on the island Some groups wiped out by volcanic activity on the island

Location of the Flores Site, Indonesia

Cultural Periods of the European Upper Paleolithic

World of the Upper Paleolithic Variable and sometimes resource-rich environment Larger populations aggregations Technology More efficient use of stone Bone, ivory and antler become more widely used raw materials Spear throwers

Innovations in Symbols More investment in grave offerings Variable social status reflected in grave offerings Over-designed artifacts Figurines Cave images

African Finds Apollo 11 Blombos Cave Pinnacle Point 28,000-26,000 ya