Four kinds of hominins lived about 1.8 mya near Lake Turkana N. Kenya: Australopithecus boisei, H. rudolfensis, H. habilis and H. erectus foraged in

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2 Four kinds of hominins lived about 1.8 mya near Lake Turkana N. Kenya: Australopithecus boisei, H. rudolfensis, H. habilis and H. erectus foraged in the same area. We don t know if they interacted.

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

4 1.9 mya to ~ 140 kya Upright Man so named because they were some of the first bipedal hominids identified Brain size cc Low forehead Pronounced Brow ridge supraorbital torus Sagital keel Nuchal torus

5 Nuchal Torus Supraorbital Tori KNM-ER 3733, ~1.7 mya E. African forms cranial capacity ~ cc

6 H. erectus brain: cc (average 900 cc) Find A. boisei and H. erectus in the same deposit Live together? Compete?

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8 First species to leave Africa Not all H. erectus left

9 Physical Characteristics Jaws were still large but smaller than those of earlier hominin Body proportions are similar to modern humans Limb proportions reflect a modern bipedal form, and suggest endurance running Narrow pelvic proportions indicate rapid brain growth continuing after birth

10 Had greater limb length, so more efficient bipedalism First with cranial capacity near range of H. sapiens Efficient scavenger of meat; gave wider range of nutrients Ranged widely from Spain to Indonesia Major change in adaptive strategies Transformed hominin evolution to human evolution Major change in adaptive strategy influenced pattern and process of human evolution

11 Note how different H. erectus is from much earlier A. afarensis.

12 Early hominin fossils have been found only in Africa, so it seems that hominins were restricted to Africa for as long as 5.0 my Close to 2.0 mya, hominins expanded out of Africa into other areas of the Old World

13 The later, more widely dispersed hominins such as H. erectus were physically larger, more committed to a terrestrial habitat and used elaborate stone tools There is some variation among the different geographical groups of these hominins, and anthropologists still debate how to classify them

14 After 2.0 mya, there s less diversity in these hominins than in their pre-australopithecine and australopithecine predecessors There is universal agreement that the hominins found outside of Africa are members of genus Homo Homo erectus is the species for which there is the most evidence

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16 The first hominin to expand into new regions of the Old World As a species, H. erectus existed for over 1.0 my We can understand its success as a hominin species based on behavioral capacities (i.e. more elaborate tool use) and physical changes (i.e. larger)

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

18 Discoveries from East Africa have established Homo erectus by 1.7 mya Some researchers see anatomical differences between the African and Asian discoveries They place African fossils into the Homo ergaster species Analyses show that H. erectus/ergaster represents closely related species and possibly geographical varieties of a single species Homo erectus Southeast Asia Homo ergaster East Africa

19 Asian H. erectus: Less robust Thinner brow ridge Brain: cc Thicker cranial bones mya African H. erectus (aka H. ergaster) More robust Thicker brow ridge Brain: cc Thinner cranial bones mya

20 Java specimen s cranial capacity: ~ cc

21 Living in different environments over much of the Old World, H. erectus populations shared several common physical traits including: Body size Brain size Cranial shape

22 H. habilis and H. erectus

23 Cranial capacities 700 cm 3 to 1250 cm 3 Brain size closely linked with overall body size H. erectus is larger-bodied than early Homo, but relative brain size is about the same Relative brain size of H. erectus is considerably less encephalized than later members of genus Homo

24 Homo Sapiens Skull

25 Thick cranial bone, large browridges (supraorbital torus [pl. tori]), and projecting nuchal torus Braincase long and low, with little forehead development Cranium wider at base, compared with earlier and later species

26 Sagittal keel, a small ridge from front to back along the sagittal suture, reflects bone buttressing in a very robust skull, rather than a specific function

27 Nuchal Torus - A projection of bone in the back of the cranium where neck muscles attach; used to hold up the head

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29 Homo erectus evolved first in Africa, supported by evidence of: 1. Earlier hominins prior to the appearance of H. erectus occurring in Africa mya fossils at East Turkana, in Kenya, and not long after at other sites in East Africa mya populations in southeastern Europe; 1.6 mya populations in Indonesia, suggesting quick migrations

30 Homo erectus fossil site and migration routes Yellow

31 The earliest H. erectus fossils come from East Turkana, from the same area where earlier australopithecine and early Homo fossils have been found It seems likely that in East Africa around mya, some form of early Homo evolved into H. erectus

32 In 1984, Kamoya Kimeu discovered a small piece of skull on the west side of Lake Turkana at the site known as Nariokotome The excavations produced the most complete H. erectus skeleton ever found Facial bones, a pelvis, and most of the limb bones, ribs, and vertebrae

33 The Nariokotome skeleton is dated to about 1.6 mya The skeleton is that of a boy about 8 years of age with an estimated height of 5 feet 3 inches May have reached 6 feet by adulthood

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35 Find by Louis Leakey in 1960, includes wellpreserved cranial vault with small part of upper face Dated at 1.4 mya, the cranial capacity is the largest of all the African H. erectus specimens The browridge is the largest known for any hominin, but the walls of the braincase are thin Similar to East African H. erectus specimens; differs from thick cranial bones in Asian H. erectus

36 Female pelvis with very wide birth canal, indicating largebrained infants in utero Newborn H. erectus may have had a brain comparable to typical modern human baby When compared with Nariokotome pelvis it suggests considerable sexual dimorphism in skeletal anatomy is linked to reproduction and body size

37 Middle Awash of Ethiopia, date 1.0 mya Complete cranium more like Asian H. erectus than most earlier East African remains discussed Discounts argument that East African fossils are different species than Asian H. erectus

38 Evolved in Africa about 2.0 mya A greater range of physical variation in specimens outside of Africa at about 1.8 mya Reached Java, Indonesia by 1.6 mya Equates to less than 200,000 years to travel from East Africa to Southeast Asia

39 The discovery of the Dmanisi materials in Republic of Georgia began in the early 1990s Four well-preserved crania, with one being almost complete Dates to ~1.77 mya

40 Best-preserved remains of hominins of this age found anywhere outside of Africa

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42 The most complete specimen has a less robust and thinner brow ridge, a projecting lower face, and a large upper canine All three Dmanisi crania have small cranial capacities A number of stone tools, similar to Olduwan industry from Africa, have been recovered at Dmanisi Remains from four individuals allows comparisons with H. erectus from other areas

43 Skull found of an older individual No teeth and evidence of severe bone loss Would have needed to be cared for

44 Six sites in eastern Java, dating from 1.6 mya to 1.0 mya, during the Early to Middle Pleistocene The Ngandong individuals may date from 53,000 to 27,000 ya Solo Man

45 Largest collection of H. erectus remains found to date 40 male and female adults and children near Beijing, at Zhoukoudian, excavated beginning in 1920s 14 skullcaps, other cranial pieces, more than 100 isolated teeth, and scattering of postcranial remains Site occupied for 530,000 years Peking Man - Zhoukoudian Cranial capacity ~1100

46 Interpretations for this site range from ritualistic treatment (burial) or cannibalism to the suggestion that the H. erectus remains are the leftovers of the meals of giant hyenas! Cultural remains of more than 100,000 artifacts indicate site occupation of several thousand years Lack of evidence of the control of fire and suggestive evidence of bone accumulation of carnivores cast doubt on whether the cave was home or hearth

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48 Reconstructed cranium of Homo erectus from Lantian, China, dated to approximately 1.15 mya Two adult females in association with firetreated pebbles and flakes Mandible with several teeth similar to those at Zhoukoudian

49 Date 800, ,000 ya, at similar age to Zhoukoudian Restored crania using imaging techniques allows comparative analysis Fauna and paleoenvironmental analysis suggests limited hunting of young and old animals

50 Closely related to Zhoukoudian finds, but later

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

52 Atapuerca region in northern Spain, 1.2 mya partial jaw with few teeth; closely resembles Dmanisi fossils; simple flake tools and animal bones Spanish paleoanthropologists place these hominins into a species called Homo antecessor Gran Dolina, dated to appx 850, ,000 ya Assigning the fossils to a particular species is problematic, based on the fragmentary nature of the remains

53 From central Italy, provisionally dated to 800, ,000 ya. A specimen close to H. erectus, or perhaps a different species?

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55 Expansion of the brain enabled H. erectus to develop sophisticated tools that span two stone tool industries: Oldowan and Acheulian Acheulian Biface - stone worked on both sides and used to cut, scrape, pound, and dig Raw materials transported more consistently and for longer distances Suggests foresight: knew they needed a stone tool in the future and carried what they regarded as useful

56 The Paleolithic is a prehistoric age distinguished by the development of stone tools known as the Old Stone Age A more accurate translation would be Old Stone From the Greek Paleo meaning old or ancient and Lithos meaning stone

57 Middle Stone Age, period in human development between the end of the Paleolithic period and the beginning of the Neolithic period It began with the end of the last glacial period over 10,000 years ago and evolved into the Neolithic period

58 Also called New Stone Age, final stage of cultural evolution or technological development among prehistoric humans It was characterized by stone tools shaped by polishing or grinding, dependence on domesticated plants or animals, settlement in permanent villages, and the appearance of such crafts as pottery and weaving Beginning of Neolithic varies by area; began as early as 6000 ya in the Middle East and as late as 3000 ya in area of Europe

59 The Paleolithic spans the entire age of prehistoric tools from Homo habilis 2.6 mya to premodern Homo sapiens 10,000 ya Usually split into lower, middle, and upper Lower Paleolithic 2.6 mya to 300,000 ya Middle Paleolithic 300,000 to 40,000 ya Upper Paleolithic 40,000 to 10,000 ya

60 Oldowan ~2.6 to 1.2 mya The Oldowan is the oldest-known stone tool industry Dating as far back as 2.6 million years ago, these tools are a major milestone in human evolutionary history: the earliest evidence of cultural behavior Homo habilis manufactured Oldowan tools

61 Acheulean ~1.6 mya to 200 kya The Oldowan is the oldest-known stone tool industry Acheulean tools were produced during the Lower Paleolithic and characterized by distinctive oval and pear-shaped "hand-axes" Acheulean stone tools are the products of Homo erectus

62 Pertaining to a stone tool industry from the Lower and Middle Pleistocene Characterized by a large proportion of bifacial tools (flaked on both sides) Multifunctional tools, including uses for butchery

63 A basic tool of the Acheulian tradition.

64 Bifaces, stone tools worked on both sides Flatter with straighter, sharper sides than Oldowan tools More efficient tool Basic Acheulian tool is the hand axe used for meat preparation Also made Scrapers, used for cleaning animal flesh and cleavers, used to break animal bones

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