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 mya 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 Find A. boisei and H. erectus in the same deposit Live together? Compete? First species to leave Africa Not all H. erectus left

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8 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

9 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

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

11 Early hominin fossils have been found only in Africa, so it seems that hominins were restricted to Africa for as long as 5 my Close to 2 mya, hominins expanded out of Africa into other areas of the Old World

12 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

13 After 2 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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15 The first hominin to expand into new regions of the Old World As a species, H. erectus existed for over 1 my We can understand its success as a hominid species based on behavioral capacities (i.e. more elaborate tool use) and physical changes (i.e. larger)

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

17 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

18 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

19 Java specimen s cranial capacity: ~ cc

20 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

21 H. habilis and H. erectus

22 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

23 Homo Sapien Skull

24 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

25 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

26 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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28 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

29 Homo erectus fossil site and migration routes

30 Homo erectus fossil site and migration routes

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 The smallest cranium of any H. erectus from anywhere in Africa Dated at 1.5 mya, the skull has a cranial capacity of only 691 cm 3 The skull shows more gracile features than other East African H. erectus individuals It s been proposed that this find is a female

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34 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

35 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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37 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

38 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

39 Middle Awash of Ethiopia, date 1 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

40 Early fossil Homo erectus from Africa KNM-ER 3833, from Koobi Fora, Kenya, 1.6 million years old KNM-ER 3733, from Ileret, Kenya, 1.65 million years old OH 9, from Olduvai Gorge, Tanzania, around 1.2 million years old KNM-WT 15000, from Nariokotome, Kenya, 1.5 million years old.

41 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

42 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

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

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45 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

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

47 Six sites in eastern Java, dating from 1.6 mya to 1 mya, during the Early to Middle Pleistocene The Ngandong individuals date from 27,000 ya

48 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 530,000 years Peking Man - Zhoukoudian Cranial capacity ~1100

49 Interpretations for this range from ritualistic treatment 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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51 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

52 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

53 Closely related to Zhoukoudian finds, but later

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

55 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

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

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58 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

59 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

60 A basic tool of the Acheulian tradition.

61 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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63 1.8 MYA in East Africa E. Turkana 1.6 MYA in Java Sangiran 1.8 MYA in Eastern Europe Dmanisi

64 Australopithecine= 4.4 mya to 1 mya Did not go extinct that long ago Overlap with genus Homo Hominin = 2.5 mya to present mya: earlier hominin gives rise to Homo H. habilis: 1.9 mya H. erectus: 1.8 mya

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68 H. erectus H. neanderthalensis H. heidelbergensis H. sapiens

69 [780,000 ya to 125,000 ya] Most of premodern hominins lived during Middle Pleistocene Known as Ice Age because of massive continental glacial fluctuations Hominins at this time were severely affected by changes in climate, flora and animal life Most dramatic effects were in Europe and N. Asia, but also affected hominins and migration routes in Africa

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71 Changing migration routes

72 Widely distributed in the Old World Africa, Asia, Europe For the first time, Europe became more permanently and densely occupied

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

74 H. heidelbergensis 850, ,000 kya Widely Distributed After Homo erectus Before Neandertals and modern humans Before naming this species, scientists referred to early human fossils showing traits similar to both Homo erectus and modern Homo sapiens as archaic Homo sapiens

75 We see geographic differences in H. heidelbergensis (like H. erectus/ H. ergaster) Europe Traits anticipate Neandertals Neandertals are a purely regional species, only in Europe Africa Traits anticipate modern humans Asia Still mostly like H. erectus

76 800 kya: Home bases (caves), Cooperative group living (healed fractures) 700 kya: Clothing (not sewn) kya: First conclusive/consistent evidence of fire 400 kya: Jabbing spears (cooperative hunting) 300 kya: Symbolic burials, Pit of Bones (Spain) 200 kya: H. erectus is almost completely gone, succeeded by H. heidelbergensis still have H. erectus in Java up to 25,000 ya

77 Ancestral or Primitive traits Large face Projecting brow ridges Low forehead Thick cranial vault Derived (unique) traits for this species Increase in brain size More rounded cranial vault Less angled occipital Vertical nose

78 Caves and open air sites Controlled FIRE Built temporary structures Hunted other animals Jabbing spears

79 Mostly remained in areas previously occupied by Homo erectus Africa probably continued to be central area of hominin occupation Largely replaced earlier hominins in previously exploited habitats

80 Earliest premodern humans had several H. erectus characteristics Large face Projecting brows Low forehead Cranial vault in some still thick H. erectus H. neandertalensis H. sapien

81 Had more derived features that were closer to H. sapiens than to H. erectus predecessors Increased brain size More rounded braincase More vertical nose Less angled back of the skull (occipital)

82 Widely distributed in Africa, Asia and Europe, replacing earlier hominins in previously exploited habitats (or coexisting as in Southeast Asia) Exhibit several H. erectus characteristics Large face, projected brows, low forehead, and thick cranial vault Increased brain size, rounded braincase, vertical nose, and reduced occipital

83 A lot of changes in the skull are visible!

84 Kabwe (Broken Hill), Zambia kya

85 Bodo cranium Cut-marks on bone Earliest hominin on hominin bone processing found so far Cannibalism!?

86 Gran Dolina Spain 850 kya oldest found so far

87 Gran Dolina finds in northern Spain may represent H. heidelbergensis, possibly dating to 850,000 ya Atapuerca site of Sima de los Huesos (pit of bones) remains of at least 28 individuals date to 500, ,000 ya

88 Dali fossils display H. erectus and H. sapiens traits 230, ,000 ya cranial capacity of 1120 cc Jinniushan, northeast China 200,000 ya cranial capacity appx 1260 cc Many Chinese researchers have argued evidence suggests regional continuity to modern populations, but others believe modern H. sapiens moved into the region and took over

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90 African and European more similar Asian- most dissimilar to both Africa H. heidelbergensis Europe H. heidelbergensis Asia Think evolves into Regional H. heidelbergensis Seemingly dead end H. sapiens H. Neanderthalensis

91 The Acheulian technology of H. erectus carried into the Middle Pleistocene with little change until near the end of the period, when it became slightly more sophisticated Some later premodern humans in Africa and Europe invented the Levallois tool making technique for controlling flake size and shape This suggests increased cognitive abilities in later premodern populations

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94 Premodern human populations continued to live in caves and open-air sites, but they may have increased their use of caves Chinese archaeologists insist that many Middle Pleistocene sites in China contain evidence of humancontrolled fire

95 Researchers found concentrations of bones, stones, and artifacts at several sites suggesting that Middle Pleistocene hominids built temporary structures There is also evidence that they exploited different food sources, fruits, vegetables, fish, seeds, nuts, and bird eggs, each in its own season They also exploited marine life, a new innovation in human evolution

96 Researchers have found little evidence supporting widely practiced advanced hunting. However, in 1995 wood spears were found at the Schöningen site in Germany These were most likely used as throwing spears to hunt large animals The bones of numerous horses were also recovered

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

98 Named for the region they were found in Germany "the Neander Valley Old spelling was Neanderthal, but the modern spelling is Neandertal the h was always silent The scientific name continues to use the h but it is still silent H. neanderthalensis or H. sapiens neanderthalensis

99 Neandertals are commonly placed by researchers into a separate species: Homo neanderthalensis However genetic evidence of interbreeding between neandertals and modern H. sapiens, suggests there was no speciation More appropriately named as a subspecies: Homo sapiens neanderthalensis

100 Brain Size: Larger than H. sapiens today (1520 cc compared to 1350 cc) perhaps adapted to cold climate metabolic efficiency Cranium: Large, long, low, and bulging at the sides Structure: Robust, barrel-chested, and powerfully muscled with shorter limbs than modern H. sapiens

101 In terms of appearance, Neanderthals were very similar to Homo sapiens However, there were some notable differences Neandertals were shorter and stockier, and had a wider rib cage, or thorax, and a larger pelvis than modern Homo sapiens

102 These differences may be directly related to a change in diet during severely cold periods Humans have a limited ability in converting protein into energy protein makes up only 30% of the human diet It is hypothesized that the Neanderthals were forced to eat a high-protein diet due to lack of available carbohydrates during glacial winters

103 An 'evolutionary adaptation to high-protein diet' It is estimated that during cold snaps ~ 75-85% of Neanderthals' calorie intake would have been animal meat large mammoths and wooly rhinoceros During harsh Ice-Age winters, carbohydrates would have been scarce, but large game thrived This situation triggered an evolutionary adaptation to a high-protein diet - an enlarged liver, expanded renal system and their corresponding morphological manifestations

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105 Almost complete skeleton Found in a flexed position Old man of La Chapelle Arthritis of the spine ~40 years old 1620 cc

106 12 Neanderthals discovered: Men, women and children Over 400 artifacts 42,000 and 44,000 years ago

107 St. Césaire, among the last Neandertals

108 Lateral view showing characteristic Neandertal traits Croatia 130, ,000 ya First intention burial site found

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110 120, ,000 ya The Tabun Cave contains a Neanderthal female, dated to about 120,000 years ago One of the most ancient human skeletal remains found in Israel

111 60,000 ya Hyoid bone recovered indication of speech capabilities

112 In Shanidar cave, in the Zagros Mountains of northeastern Iraq, fieldworkers found partial skeletons of nine individuals, four of them deliberately buried Burials span 65,000 to 35,000 years ago Shanidar 1 is a skeleton of a male who lived to be 30 to 45 years old; a very old age for prehistoric hominin His height is estimated at 5 feet 7 inches, and his cranial capacity is 1,600 cc

113 He had injuries that would have made it impossible to perform normal activities leading researches to believe he must have been helped by others One-armed, partially blind, and crippled Could he represent Neandertal compassion for the disabled?

114 Teshik-Tash site in Usbvekistan Remains of Neandertal child associated with tools of the Mousterian industry

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118 Denisova Cave, southern Siberia A treasure trove of fossils from both Neandertal and H. Sapiens spanning 125,000 years But the cave held more: Finger bone of a juvenile female and two teeth from other individuals dated to 41,000 ya

119 A green bracelet made of polished chlorite was found in the same layer as the Denisovan bone and teeth Dating to 40,000 ya, it is thought to have been made by the Denisovan hominins This would make it the oldest piece of jewelry ever discovered

120 The bone was so well preserved they were able to sequence much of the genome DNA evidence shows significant genetic distance from both Homo sapiens and Neandertals Denisovans and Neandertals shared a common ancestor ~640,000 ya Denisovans, Neandertals, and modern humans shared a common ancestor ~804,000 ya But there is a connection: 3-5% of the DNA of populations of New Guinea, indigenous people of Australia, and aboriginals of the Philippines have Denisovan DNA

121 Researchers attempted to determine how Tibetans were able to overcome the effects of hypoxia in low oxygen environments and altitudes Hypoxia lack of oxygen to tissues, often caused by high altitudes EPAS-1 Gene key behind this beneficial Tibetan ability Regulates the body s reaction to low oxygen environments it allows Tibetans to produce less hemoglobin and fewer red blood cells

122 No other living human population has this gene Neandertals didn t have this gene The EPAS-1 gene was found in the Denisovan female