H. habilis H. rudolfensis H. erectus. H. ergaster H. antecessor. H. heidelbergensis H. sapiens neanderthalensis H. floresiensis H.

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2 H. habilis H. rudolfensis H. erectus H. ergaster H. antecessor H. heidelbergensis H. sapiens neanderthalensis H. floresiensis H. sapiens

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4 Homo floresiensis A recent discovery on Flores Island, Indonesia, has become the source of much debate in anthropology

5 Could populations of H. erectus have survived on the Javanese island of Flores to 50,000 ya, long after H. erectus had disappeared in China and East Africa? Extremely small bodied and small brained hominins Isolated island populations can rapidly diverge from relatives elsewhere when natural selection favors reduced body size

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7 The small stature and brain of H. floresiensis may have resulted from island dwarfism; an evolutionary process that results from long-term isolation on a small island with limited food resources and a lack of predators. Pygmy elephants on Flores, now extinct, showed the same adaptation.

8 Homo floresiensis Hobbits 100 to 50 kya Previously thought to have lasted until 12 kya All were very small

9 Stood ~3.5 feet tall Tiny brains Large teeth for their small size No chins Receding forehead Relatively large feet due to their short legs.

10 Despite their small body and brain size, H. floresiensis made and used stone tools, hunted small elephants and large rodents, coped with predators such as giant Komodo dragons, and may have used fire.

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12 Discovered in 2013 in South Africa Naledi means star, found in Rising Star Cave No dating method available yet mixed soil sediment in the cave make dating difficult (best estimate is in the 2.0 mya range)

13 Recent analysis of the fossils suggest an adaptation to long distance walking or even endurance running Most similar so far to Homo erectus or Australopithecus sediba Flared pelvis, curved fingers, primitive shoulder and ribs (Australopithecus feature) But Homo legs, thumb, vertebrae Brain: ~500 cc, but little constriction

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15 Intentional burial - Though such advanced behavior is unknown in other primitive hominins, there appears to be no other option for why the bones are there.

16 A. afarensis H. erectus H. naledi Lucy Turkana Boy

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18 H. habilis H. rudolfensis H. erectus H. ergaster H. antecessor H. heidelbergensis H. sapiens neanderthalensis H. floresiensis H. sapiens

19 Close to 200,000 ya, the first modern Homo sapiens populations appeared in Africa Who were they? Why were they so successful? What happened to other hominins, such as the Neandertals

20 200,000ya

21 Modern humans = anatomically modern H. sapiens - AMH Premodern humans = have similarities to predecessors (H. erectus) and successors (H. sapiens). H. heidelbergensis possible ancestors of the earliest modern H. sapiens sometimes called Archaic H. sapiens H. sapiens neandertalensis possibly evolved from later H. heidelbergensis populations in Europe. Early humans H. habilis - first tool makers H. rudolfensis Africa, same time as H. habilis, but larger cranial capacity H. erectus more like modern humans in their adaptive pattern, first humans to spread out of Africa into Asia and Europe. H. ergaster African H. erectus H. antecessor Spanish H. erectus

22 ~200 kya, the first modern Homo sapiens evolved in Africa ~100 kya, across most of the Old World, even Australia Homo sapiens (or Homo sapiens sapiens) - all contemporary populations aka anatomically modern human - AMH

23 Different models of how H. sapiens evolved Multiregional Continuity Model Replacement Model Assimilation Model

24 Wolpoff s model All populations continued evolutionary development from H. heidelbergensis to AMH simultaneously due to gene flow No extinction, H. erectus/archaic/h. heidelbergensis/amh are simply different names for the same species over time Regional/Genetic continuity in morphology throughout lineages H. erectus leads to H. heidelbergensis into Modern humans in Africa, Europe, and E. Asia simultaneously One-line summary: Everything evolves across multiple regions at the same time, and in the same way, due to gene flow

25 Modern humans evolved in a single line of evolution from Homo erectus to H. heidelbergensis (archaic humans) to modern humans (H. sapiens) over the past 1.8 million years Regional differences evolved over time, but species were tied by gene flow

26 Stringer and Andrews AMH populations arose in Africa in the last 200,000 years Migrated from Africa, completely replacing populations in Europe and Asia. No gene flow. Does not account for the transition from archaic (heidelbergensis) to modern anywhere except Africa One-line summary: African origin replaces whatever was existing elsewhere

27 Around 200,000 ya modern homo sapiens emerged as a new species in Africa, splitting off from H. heidelbergensis population 100,000 ya H. sapiens populations left Africa, spread out, replaced premodern populations (Neandertals) in Europe and Asia

28 Doesn t account for premodern to modern H. sapiens anywhere but Africa Suggests that Neandertals were a different species Homo neanderthalensis New DNA evidence suggests that there was interbreeding between H. sapiens populations and Neandertals between 80,000 and 50,000 kya This means a partial, not complete, replacement was more likely

29 Regional Continuity Model Transition to modern humans took place in different regions (Europe, Asia, Africa) Migration, interbreeding, gene flow and natural selection led to genetic mixing that resulted in a single species = modern H. sapiens. African Partial Replacement Model Modern humans arose only in Africa and migrated from Africa, replacing premodern populations in Europe and Asia. Partial replacement -Recent DNA evidence shows some interbreeding between Neandertal and early modern humans

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31 Smith/ Trinkaus model Both the complete replacement and the multiregional continuity models have difficulty accounting for all of the fossil and genetic data The assimilation (or partial replacement) model takes a middle ground and incorporates both of the old models

32 Proposes that the first modern humans did evolve in Africa, but when they migrated into other regions they did not simply replace existing human populations. Rather, they interbred to a limited degree with late archaic humans resulting in hybrid populations. In Europe the first modern humans appear in the archaeological record rather suddenly around 45-40,000 years ago The abruptness of the appearance of these Cro-Magnon people could be explained by their migrating into the region from Africa via an eastern Mediterranean coastal route They shared Europe with Neandertals for another 12,000 years

33 DNA sequences indicates that there has been interbreeding between people living in Asia, Europe, and Africa for at least 600,000 years This is consistent with the hypothesis that humans expanded again and again out of Africa and that these emigrants interbred with existing populations in Asia and Europe It is also possible that migrations were not only in one direction-- people could have migrated into Africa as well

34 Premodern humans Beginning about 130,000 years ago, populations of premodern (archaic) humans such as H. Heidelbergensis started evolving into anatomically modern Homo sapiens All fossil humans since 28,000 years ago are anatomically modern in form

35 Cro Magnon 1 - One of the more famous early H. sapiens Found in France Named after the location Cro (hole or cavity) and Magnon (owner of the property) Shows physical characteristics of anatomically modern H. sapiens Homo sapiens, Cro-Magnon 1

36 Homo sapiens, Cro-Magnon 1 Homo heidelbergensis Differences between Homo sapiens, Cro-Magnon and premodern human H. heidelbergensis: Skull - high and well rounded Back of skull rounded with occipital bun Forehead - Forehead rises vertically above eye orbits, does not slope Brow ridges supraorbital tori are small Face less prognathic

37 Neandertal modern Homo sapiens Notice the chin modern H. sapiens have one and Neandertal s do not.

38 Dates Site Hominin Evolutionary Significance 195,000 ya Omo Ethiopia H. sapiens Oldest modern human; two crania found, one more modern looking than the other 154, ,000 ya Herto Ethiopia H. sapiens idaltu Well-preserved cranium; bestpreserved early modern human found anywhere and best dated from this time.

39 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 H. sapiens sapiens Large sample; modern, but some individuals fairly robust; early date

40 Herto cranium from Ethiopia, dated 160,000 to 154,000 ya best dated fossils from this time Older than any other equally modern H. sapiens anywhere Mosaic of modern and premodern traits Very large, and extremely long cranial vault 1450 cc size well within range of contemporary H. sapiens Large, arching browridge and projecting occipital protuberance Face does not project in stark contrast to Neandertals. Clearly H. sapiens, not identical to modern humans, but near-modern

41 Most conclusive fossil evidence for an African origin of modern humans Right age (older than any other H. sapiens) Right place (Ethiopia, East Africa) Right mix of pre-modern and modern features one would expect Compatible with strong genetic data indicating African origin and replacement model for human origins

42 Skhül 5. (a) 130, ,000 ya Qafzeh 6 (b)120,000-92,000 ya The vault height, forehead, and lack of prognathism (protrusion of lower jaw) are modern traits Contemporary with Neandertals in Region Are definitely modern humans, but some show pre-modern features

43 Zhoukoudian 27,000 ya Most Asian H. sapiens date to less than 40,000 ya

44 6,000-5,000 ya Rome Buried intertwined with each other

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46 Locations of major H. sapiens fossils.

47 Tianyuan Cave, China fossil important Dated close to 40,000 ya Skeleton shows mostly modern features, with a few archaic pre-modern characteristics Some evidence of interbreeding in China with resident archaic (premodern) populations

48 50,000 ya modern humans inhabited areas including New Guinea and Australia Earliest finds so far are from Lake Mungo, SE Australia 30,000-25,000 ya Finds from Kow Swamp 14,000-9,000 ya different from those from Lake Mungo Have archaic features, including receding foreheads, heavy supraorbital tori, and thick bones

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52 Abrigo do Lagar Velho site 24,500 ya 4-year old child Highly mixed set of anatomical features May be a result of interbreeding between Neandertals and modern humans If so, would support partial replacement model of human origins Genetic evidence is unequivocal: Neandertals and modern humans did interbreed at some point

53 Homo Sapiens Neandertals

54 Genetics Find lots of different combinations of alleles in humans There are 24 combinations, and we find them all in Africa More genetic diversity in Africa than in any other part of world Especially in South Africa Only 8 of these combinations move through the rest of the world Small population migrated EVERYWHERE

55 Humans have very, very, very low genetic differences between each other, if any 99.9% identical No biological races or sub-species

56 Above are the 5 different tool industries/technology of the Upper Paleolithic.

57 Major environmental shifts warming trend partially melted glacial ice Result Eurasia covered by tundra and steep, treeless country with lakes and marshes Created enormous pasture for herbivores which gave carnivorous animals a steady food supply Abundant food supply for humans as well, along with fish and fowls

58 Paleolithic people spread out over Eurasia, living in caves and open-air camps More elaborate burials Age of innovation Major adaptive advantage more sophisticated technology Larger populations aggregations More labor intensive architecture

59 More elaborate burials than before Grave goods - thousands of ivory beads, long spears of mammoth tusks, ivory engravings, jewelry Variable social status reflected in grave offerings Sungir, Russia 24,000 year old burial and artist s recreation

60 Solutrean tools skillfully made with more aesthetic details More specialization in tools

61 Magdalenian tools - More efficient use of stone with skilled craftsmanship Bone, ivory and antler become more widely used raw materials Spear throwers increased efficiency in hunting Barbed harpoon Bows and arrows used for the first time 1-4 Solutrean 5-9 Magdalenian

62 Punch blade technique more efficient provided abundance of standardized stone blades. Could be used to work wood, bone, antler.

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64 Cave paintings Small sculptures Venus figurines

65 Nothing representing cave painting until 30,000-40,000 ya (preservation problem?) They depict what they see Are invariably large mammals and stick people Most are extremely recent, ~10kya

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68 Lascaux is the setting of a complex of caves in southwestern France

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71 Altamira is a cave in Cantabria, Spain Created between 18,500 and 14,000

72 Les trois freres cave What animal is this?!

73 Painted rock art in rock shelter site at Apollo 11 dates to 28,000-26,000 ya Remarkable bone tools, beads, decorate ocher fragments from Blombos Cave dates to 73,000 ya Ocher, exploitation of shellfish, small stone blades at Pinnacle Point date to 165,000 ya earliest evidence from anywhere of behaviors thought to be characteristic of modern humans

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76 November 23: Last Quiz! November 28: Course Overview November 30: Review Game! November 30: Assignment 4 Due - beginning of class December 5: NO CLASS December 7: Final Exam same time as class