fossil hominins: from australopithecus to homo

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Fossil Hominins Fossil Hominins From Australopithecus to From Australopithecus to Homo Homo

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Compares the Fossil Hominins from Australopthecus afarensis to Homo Sapiens

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Page 1: Fossil Hominins: From Australopithecus to Homo

Fossil HomininsFossil Hominins

From Australopithecus to HomoFrom Australopithecus to Homo

Page 2: Fossil Hominins: From Australopithecus to Homo

Model of Human Evolution: Model of Human Evolution: Australopithecus to HomoAustralopithecus to Homo

Australopithecus afarensis to A. africanusAustralopithecus afarensis to A. africanus: : Gracile AustralopithecinesGracile Australopithecines

Paranthropus robustus and boisei:Paranthropus robustus and boisei: Robust Robust Australopithecines—Dead end?Australopithecines—Dead end?

A. africanus A. africanus to to Homo habilisHomo habilis: Rise of tool : Rise of tool manufacture?manufacture?

H. habilisH. habilis to to H. erectus: H. erectus: Global spread; Global spread; increased tool assemblageincreased tool assemblage

H. erectus H. erectus to to H. sapiens:H. sapiens: Tool specialization Tool specialization and population explosionand population explosion

H. neanderthalensis: Dead end?H. neanderthalensis: Dead end?

Page 3: Fossil Hominins: From Australopithecus to Homo

Fossil Hominins: General Fossil Hominins: General TrendsTrends

Large bulbous craniumLarge bulbous cranium Short face compared to apeShort face compared to ape Vertical carriage of headVertical carriage of head Hands and Forelimbs Adapted to Tool Hands and Forelimbs Adapted to Tool

Making and UseMaking and Use Bipedal Structure of Postcranial SkeletonBipedal Structure of Postcranial Skeleton

Page 4: Fossil Hominins: From Australopithecus to Homo

Fossil Trends: Encephalization Fossil Trends: Encephalization (Cranial Capacity Increase)(Cranial Capacity Increase)

A. afarensis:A. afarensis: 390-500 cc; av. 440 cc 390-500 cc; av. 440 cc A. africanus: A. africanus: 435-530 cc; av. 450 cc435-530 cc; av. 450 cc A./P robustus: A./P robustus: 520 cc, one specimen520 cc, one specimen A.P. boisei: A.P. boisei: 500-530 cc; av. 515 cc.500-530 cc; av. 515 cc. H. habilis: H. habilis: 500-800 cc; av. 680 cc.500-800 cc; av. 680 cc. H. erectus: H. erectus: 750-1250 cc; av. 1000 cc750-1250 cc; av. 1000 cc Neanderthal: 1300-1750 cc. av: 1450Neanderthal: 1300-1750 cc. av: 1450 H. (s.) sapiens: H. (s.) sapiens: 900-2350 cc. av. 1400900-2350 cc. av. 1400

Page 5: Fossil Hominins: From Australopithecus to Homo

Fossil Trends: Forelimbs and Fossil Trends: Forelimbs and HandsHands

Shortened forelimbShortened forelimb Hands (manipulation, not locomotion)Hands (manipulation, not locomotion) Enlarged thumbEnlarged thumb Straight, noncurved fingerStraight, noncurved finger Enhanced finger sensitivityEnhanced finger sensitivity

Page 6: Fossil Hominins: From Australopithecus to Homo

Fossil Hominins: General Fossil Hominins: General Trends--BipedalismTrends--Bipedalism

S-shaped vertebrae (backbone)S-shaped vertebrae (backbone) Short, wide, bowl-shaped pelvisShort, wide, bowl-shaped pelvis Femoral head (ball of femur at pelvis) Femoral head (ball of femur at pelvis)

angled and strengthenedangled and strengthened Lengthened hindlimbLengthened hindlimb Angle of knee: femur “slopes” to pelvisAngle of knee: femur “slopes” to pelvis Platform (arched) structure of footPlatform (arched) structure of foot Nonopposable big toe; toes not curved Nonopposable big toe; toes not curved

Page 7: Fossil Hominins: From Australopithecus to Homo

Lucy (Lucy (Australopithecus afarensisAustralopithecus afarensis) ) and Us (Homo sapiens)and Us (Homo sapiens)

Note the Following:Note the Following: Shorter (3’6”)Shorter (3’6”) Longer armsLonger arms Curved fingersCurved fingers Shorter lower legsShorter lower legs Greater prognathismGreater prognathism Sloped foreheadSloped forehead Smaller cranial capacitySmaller cranial capacity What are the Similarities?What are the Similarities? Hint: it’s all related to bipedalismHint: it’s all related to bipedalism

Page 8: Fossil Hominins: From Australopithecus to Homo

Bipedalism: A. afarensis and H. Bipedalism: A. afarensis and H. sapiens compared, Fine Pointssapiens compared, Fine Points

Page 9: Fossil Hominins: From Australopithecus to Homo

When We Became Bipedal When We Became Bipedal (According to Gary Larson)(According to Gary Larson)

““Hey! Look! No Hey! Look! No hands!”hands!”

(Does he look like (Does he look like Lucy to you. . .?)Lucy to you. . .?)

Page 10: Fossil Hominins: From Australopithecus to Homo

Gracile and Robust Gracile and Robust AustralopithecinesAustralopithecines

For For A. africanusA. africanus (top), note: (top), note: Somewhat rounder skullSomewhat rounder skull No Sagittal crestNo Sagittal crest Prognathous jawPrognathous jaw For Paranthropus boisei, note:For Paranthropus boisei, note: Sagittal crest (ate a lot of veggies)Sagittal crest (ate a lot of veggies) Massive lower jaw (mandible)Massive lower jaw (mandible) Flatter faceFlatter face Massive cheek bones (zygomatic Massive cheek bones (zygomatic

arch)arch)

Page 11: Fossil Hominins: From Australopithecus to Homo

Summary of AustralopithecinesSummary of Australopithecines

Cranial capacity increased marginallyCranial capacity increased marginally All australopithecines hadAll australopithecines had Sloping foreheadsSloping foreheads Prominent brow ridgesProminent brow ridges Prognathous lower face and jawsPrognathous lower face and jaws Bipedal postcranial skeletonsBipedal postcranial skeletons Robust forms probably were dead endsRobust forms probably were dead ends Graciles likely evolved toward Graciles likely evolved toward HomoHomo. .

Page 12: Fossil Hominins: From Australopithecus to Homo

Australopithecus and Homo Australopithecus and Homo Compared—Frontal ViewCompared—Frontal View

Left: Left: A. africanusA. africanus Right: Right: H. habilisH. habilis Note:Note: Different Cranial Different Cranial

CapacitiesCapacities Brow Ridge SizeBrow Ridge Size

Page 13: Fossil Hominins: From Australopithecus to Homo

Australopithecus and Homo Australopithecus and Homo Compared—Side ViewCompared—Side View

Top: A. africanusTop: A. africanus Bottom: H. habilisBottom: H. habilis Compare:Compare: Mass of JawsMass of Jaws Size of CraniaSize of Crania PrognathismPrognathism

Page 14: Fossil Hominins: From Australopithecus to Homo

Postorbital ConstrictionPostorbital Constriction

Left: Homo erectusLeft: Homo erectus Right: Australopithecus Right: Australopithecus

africanusafricanus Note the narrower Note the narrower

constriction of A. constriction of A. africanus’s postorbital africanus’s postorbital constriction than that constriction than that of H. erectusof H. erectus

Page 15: Fossil Hominins: From Australopithecus to Homo

Homo habilis: Homo habilis: The First Known The First Known ToolmakerToolmaker Note the following:Note the following: Face is much flatterFace is much flatter Reduced brow ridge (supraorbital Reduced brow ridge (supraorbital

torus) torus) Larger cranial capacity (680 cc.)Larger cranial capacity (680 cc.) Toolmaking TechniqueToolmaking Technique HammerstoneHammerstone used to strike used to strike A A core core (lump of stone) to knap(lump of stone) to knap A A Flake Flake (stone chip)(stone chip) Note: Note: Stone has to be crystalline Stone has to be crystalline

(so it will fracture predictably)(so it will fracture predictably)

Page 16: Fossil Hominins: From Australopithecus to Homo

Homo habilis According to Gary Homo habilis According to Gary LarsonLarson

Page 17: Fossil Hominins: From Australopithecus to Homo

Australopithecines and Homo Australopithecines and Homo Compared ICompared I

Cranial capacityCranial capacity Australopithecines: 400-530 ccAustralopithecines: 400-530 cc Homo: 500-2300Homo: 500-2300 Maximum braincase widthMaximum braincase width Australopithecines: low on skullAustralopithecines: low on skull Homo: near topHomo: near top Postorbital constrictionPostorbital constriction

Australopithecines: markedAustralopithecines: markedHomo: moderate to slight Homo: moderate to slight

Page 18: Fossil Hominins: From Australopithecus to Homo

Australopithecines and Homo Australopithecines and Homo Compared IICompared II

Supraorbital torus (brow ridge)Supraorbital torus (brow ridge) Australopithecines: large to moderateAustralopithecines: large to moderate Homo: large to slightHomo: large to slight Zygomatic archZygomatic arch Australopithecines: large, flaringAustralopithecines: large, flaring Homo: small, not flaringHomo: small, not flaring

Page 19: Fossil Hominins: From Australopithecus to Homo

Australopithecines and Homo Australopithecines and Homo Compared IIICompared III

Facial size relative to brain caseFacial size relative to brain case Australopithecines: largeAustralopithecines: large Homo: smallHomo: small JawJaw A: Massive and prognathic; no chinA: Massive and prognathic; no chin H: Not massiveH: Not massive Prognathism slight to nonexistent;Prognathism slight to nonexistent; Chin present in sapientsChin present in sapients Molars and premolarsMolars and premolars Australopithecines: large; Australopithecines: large; afarensisafarensis with diastema with diastema Homo: smallHomo: small

Page 20: Fossil Hominins: From Australopithecus to Homo

Australopithecines and Homo Australopithecines and Homo Habilis Compared: SkullsHabilis Compared: Skulls

General trendsGeneral trends Encephalization: Cranial capacity increasesEncephalization: Cranial capacity increases Dentition: Cheek teeth are reducedDentition: Cheek teeth are reduced Sagittal Crest (where chewing muscles Sagittal Crest (where chewing muscles

attach)attach) A./P. robustus and boisei: A./P. robustus and boisei: pronouncedpronounced A. africanus: A. africanus: sagittal keel or absentsagittal keel or absent H. habilis: H. habilis: absentabsent

Page 21: Fossil Hominins: From Australopithecus to Homo

Australopithecines and Homo Australopithecines and Homo Habilis Compared: Skull/FaceHabilis Compared: Skull/Face

BraincaseBraincase A./P. robustus/boisei: A./P. robustus/boisei: less roundedless rounded A. africanus: A. africanus: more roundedmore rounded H. habilis:H. habilis: most rounded of the three most rounded of the three Zygomatic archZygomatic arch A./P. robustus/boisei: very pronouncedA./P. robustus/boisei: very pronounced A. africanus: A. africanus: less pronouncedless pronounced H. habilis: H. habilis: far less pronounced than the far less pronounced than the

australopithecinesaustralopithecines

Page 22: Fossil Hominins: From Australopithecus to Homo

Homo habilis: Hands and FeetHomo habilis: Hands and Feet

HandsHands Curvature of finger bones are apelike, indicate Curvature of finger bones are apelike, indicate

powerful grip (arboreal)powerful grip (arboreal) Indications of greater manipulative skillIndications of greater manipulative skill Larger blood supply to hand than earlier Larger blood supply to hand than earlier

hominidshominids Evidence of greater nerve supplyEvidence of greater nerve supply Feet: existing fragments indicate modern form:Feet: existing fragments indicate modern form: Remains lacked toesRemains lacked toes

Page 23: Fossil Hominins: From Australopithecus to Homo

Tool Traditions: Oldowan Tool Traditions: Oldowan

Named after Olduvai GorgeNamed after Olduvai Gorge Among the finds at Olduvai:Among the finds at Olduvai: Side chopper, a core toolSide chopper, a core tool Several flake tools, includingSeveral flake tools, including End scraperEnd scraper Side scraperSide scraper BurinBurin Utilized flakes of unknown functionUtilized flakes of unknown function Belongs to Lower Paleolithic Belongs to Lower Paleolithic

Page 24: Fossil Hominins: From Australopithecus to Homo

Manufacturing ChoppersManufacturing Choppers

ProcedureProcedure Knapper strikes a spherical piece of stoneKnapper strikes a spherical piece of stone Flake falls off opposite sideFlake falls off opposite side Tool flipped over and procedure repeatedTool flipped over and procedure repeated Several blows create a cutting edgeSeveral blows create a cutting edge Requirements reflect IntelligenceRequirements reflect Intelligence Planning and foreknowledge of designPlanning and foreknowledge of design Knowledge of breakage pattern of rockKnowledge of breakage pattern of rock Hand-eye coordinationHand-eye coordination

Page 25: Fossil Hominins: From Australopithecus to Homo

Oldowan TraditionOldowan Tradition

End chopperEnd chopper Heavy duty scraperHeavy duty scraper Flake scraperFlake scraper Spheroid Spheroid

HammerstoneHammerstone ChopperChopper Horn core tool or Horn core tool or

diggerdigger

Page 26: Fossil Hominins: From Australopithecus to Homo

Homo habilis and Homo erectusHomo habilis and Homo erectus

Compared to Compared to H. habilis, H erectus H. habilis, H erectus had:had: Larger brain (1000 cc vs 680 cc average)Larger brain (1000 cc vs 680 cc average) Forehead flatter, less slopingForehead flatter, less sloping More rounded occipital torusMore rounded occipital torus endocasts indicate hemispheric endocasts indicate hemispheric

asymmetryasymmetry Homo erectus and Homo sapiensHomo erectus and Homo sapiens

Page 27: Fossil Hominins: From Australopithecus to Homo

Homo erectusHomo erectus or or ergasterergaster

Note:Note: Apelike but larger craniumApelike but larger cranium Postcranial SkeletonPostcranial Skeleton Vertebrae: S ShapedVertebrae: S Shaped Ribcage: Not funnel shaped, now Ribcage: Not funnel shaped, now

like ourslike ours Pelvis: Bowl shapedPelvis: Bowl shaped Angle of ThighboneAngle of Thighbone

Page 28: Fossil Hominins: From Australopithecus to Homo

Homo erectus and Homo Homo erectus and Homo Sapiens: Cranium (Braincase)Sapiens: Cranium (Braincase)

Forehead (Frontal)Forehead (Frontal) H. erectus: H. erectus: sloping; low and flatsloping; low and flat H. sapiens: H. sapiens: vertical, indicating frontal lobevertical, indicating frontal lobe Supraorbital torus (brow ridge)Supraorbital torus (brow ridge) H. erectus: H. erectus: prominent--extending as a barprominent--extending as a bar H. sapiens: H. sapiens: slight or absentslight or absent Occipital torus:Occipital torus: H. erectus: H. erectus: presentpresent H. sapiens: H. sapiens: slight or absentslight or absent

Page 29: Fossil Hominins: From Australopithecus to Homo

Homo erectus and Homo Homo erectus and Homo sapiens: Cranium and Facesapiens: Cranium and Face

Sagittal keelSagittal keel H. erectus: H. erectus: present; vestige of crest?present; vestige of crest? H. sapiens: H. sapiens: slight or absentslight or absent Postorbital constrictionPostorbital constriction H. erectus: H. erectus: pronouncedpronounced H. sapiens: H. sapiens: slight or nonexistentslight or nonexistent

Page 30: Fossil Hominins: From Australopithecus to Homo

Homo erectus and Homo Homo erectus and Homo sapiens: Facial Skeletonsapiens: Facial Skeleton

Facial skeletionFacial skeletion H. erectus: H. erectus: Relatively large, with large Relatively large, with large

orbits and nasal openingorbits and nasal opening H. sapiens: H. sapiens: Relatively small, with small Relatively small, with small

orbits and nasal openingorbits and nasal opening Prognathism (jutting jaw)Prognathism (jutting jaw) H. erectus: H. erectus: PronouncedPronounced H. sapiens: H. sapiens: minimal or nonexistentminimal or nonexistent

Page 31: Fossil Hominins: From Australopithecus to Homo

Homo erectusHomo erectus and and Homo sapiensHomo sapiens skullsskulls

Compare:Compare: Brow ridges (supraorbital tori)Brow ridges (supraorbital tori) PrognathismPrognathism Constriction behind eye sockets (postorbital constriction)Constriction behind eye sockets (postorbital constriction) Presence versus absence of chinPresence versus absence of chin

Page 32: Fossil Hominins: From Australopithecus to Homo

Tool Traditions: AcheuleanTool Traditions: Acheulean

Named after St. AcheulNamed after St. Acheul Characteristics of Acheulean handaxeCharacteristics of Acheulean handaxe Bifacial: both sides knappedBifacial: both sides knapped Symmetrical in breadthSymmetrical in breadth Shaped to a point on one endShaped to a point on one end The edge is thin and sharpThe edge is thin and sharp Broad end is curved, but edge is still sharpBroad end is curved, but edge is still sharp Part of Lower Paleolithic Part of Lower Paleolithic

Page 33: Fossil Hominins: From Australopithecus to Homo

Acheulean Axe as “Swiss Army Acheulean Axe as “Swiss Army Knife”; Abbevillean variationKnife”; Abbevillean variation

Swiss Army Rock?Swiss Army Rock? Sharp tip: used for piercingSharp tip: used for piercing Thin edge: used for cutting (hide or meat off Thin edge: used for cutting (hide or meat off

bone)bone) Broad end: used for chopping or scrapingBroad end: used for chopping or scraping Abbevillean Variation:Abbevillean Variation: Bifacial, like the AcheuleanBifacial, like the Acheulean Not quite so symmetricalNot quite so symmetrical Olduvai specimen: transitional type?Olduvai specimen: transitional type?

Page 34: Fossil Hominins: From Australopithecus to Homo

Manufacturing Acheulean Manufacturing Acheulean HandaxesHandaxes

A demanding taskA demanding task Symmetrical, finely shapedSymmetrical, finely shaped Dozens of flakes removed, from 25 to 75Dozens of flakes removed, from 25 to 75 Each flake blow must be precisely positionedEach flake blow must be precisely positioned Core must be turned over again and againCore must be turned over again and again to maintain symmetryto maintain symmetry to keep edge straightto keep edge straight All the exterior rind (All the exterior rind (cortexcortex) was removed ) was removed

Page 35: Fossil Hominins: From Australopithecus to Homo

Abbevillian and Acheulean Abbevillian and Acheulean HandaxesHandaxes

Left: Abbevillian. Note asymmetry, rough retouchLeft: Abbevillian. Note asymmetry, rough retouch Right: Acheulean. Note symmetry, fine retouchRight: Acheulean. Note symmetry, fine retouch

Page 36: Fossil Hominins: From Australopithecus to Homo

Homo heidelbergensisHomo heidelbergensis or or “Archaic” “Archaic” Homo sapiensHomo sapiens

Left: Skull. Note heavy brow ridge, prognathismLeft: Skull. Note heavy brow ridge, prognathism Right: Mandible. Note arc-like dental arcade, absence Right: Mandible. Note arc-like dental arcade, absence

of diastema, absence of chin of diastema, absence of chin

Page 37: Fossil Hominins: From Australopithecus to Homo

Manufacturing Levallois Cores Manufacturing Levallois Cores and Flakesand Flakes

KnappersKnappers Draw outline of flake on stone moduleDraw outline of flake on stone module Strikes flake of desired shapeStrikes flake of desired shape Requires knowledge of breakage pattern of Requires knowledge of breakage pattern of

rockrock Prepares rock beforehand to control how rock Prepares rock beforehand to control how rock

breaks when struckbreaks when struck Ensure right shape (e.g. cutting, perforation, Ensure right shape (e.g. cutting, perforation,

piercing) is struckpiercing) is struck

Page 38: Fossil Hominins: From Australopithecus to Homo

Levallois Flake and Flaking Levallois Flake and Flaking TechniqueTechnique

Page 39: Fossil Hominins: From Australopithecus to Homo

Homo neanderthalensisHomo neanderthalensis: Skeleton: Skeleton

Left:Left: Homo Homo neanderthalensisneanderthalensis

RightRight: : Homo sapiensHomo sapiens CompareCompare Relative thickness of Relative thickness of

bonesbones Breadth of ribcagesBreadth of ribcages Size of skullsSize of skulls

Page 40: Fossil Hominins: From Australopithecus to Homo

Homo neanderthalensis: Homo neanderthalensis: CraniumCranium

Left:Left: H. neanderthalensisH. neanderthalensis: note larger cranial size, occipital bun, : note larger cranial size, occipital bun, prognathism, brow ridgeprognathism, brow ridge

RightRight: : H. sapiensH. sapiens: Note rounded cranium, presence of chin, absence of : Note rounded cranium, presence of chin, absence of prognathism and brow ridgeprognathism and brow ridge

Page 41: Fossil Hominins: From Australopithecus to Homo

Mousterian TraditionMousterian Tradition

Positively identified with NeanderhalsPositively identified with Neanderhals Le Moustier, France is a Neanderthal siteLe Moustier, France is a Neanderthal site Belongs to Belongs to Middle PaleolithicMiddle Paleolithic More sophisticated than Oldowan or More sophisticated than Oldowan or

Acheulean, both Acheulean, both Lower PaleolithicLower Paleolithic

Page 42: Fossil Hominins: From Australopithecus to Homo

Mousterian Tool AssemblageMousterian Tool Assemblage

Sample includes Scrapers, Points, and Sample includes Scrapers, Points, and HandaxesHandaxes

Page 43: Fossil Hominins: From Australopithecus to Homo

Upper Paleolithic: The Great Upper Paleolithic: The Great Leap Forward?Leap Forward?

Probably begins about 50,000 BPProbably begins about 50,000 BP Primary AttributesPrimary Attributes Shift from flake tools to bladesShift from flake tools to blades Subsistence on greater range of animal Subsistence on greater range of animal

and plant speciesand plant species Larger sitesLarger sites Increase of bone, antler, ivory, shell, and Increase of bone, antler, ivory, shell, and

other materials for toolsother materials for tools

Page 44: Fossil Hominins: From Australopithecus to Homo

Upper Paleolithic: Associated Upper Paleolithic: Associated AttributesAttributes

Associated AttributesAssociated Attributes Greater use of “imported” goods: Greater use of “imported” goods: raw materials obtainable only fromraw materials obtainable only from great distances from inhabited sitesgreat distances from inhabited sites which suggests tradewhich suggests trade More elaborate burials, with grave goodsMore elaborate burials, with grave goods Appearance and elaborate use of symbols Appearance and elaborate use of symbols

and works of art.and works of art.

Page 45: Fossil Hominins: From Australopithecus to Homo

Upper Paleolithic: The BladesUpper Paleolithic: The Blades

Blades begin roughly 40,000 Years BPBlades begin roughly 40,000 Years BP Comparative efficiencyComparative efficiency Levallois cores may produce 5 flakesLevallois cores may produce 5 flakes Many more blades could be produced from Many more blades could be produced from

same core--and with longer cutting edgesame core--and with longer cutting edge Unlike other traditions, blade traditions are Unlike other traditions, blade traditions are

shorter livedshorter lived Oldowan: from ca.2.5 m. yrs BP Oldowan: from ca.2.5 m. yrs BP Acheulean: from ca 1.9 m. yrs BPAcheulean: from ca 1.9 m. yrs BP

Page 46: Fossil Hominins: From Australopithecus to Homo

Upper Paleolithic AssemblageUpper Paleolithic Assemblage

Upper Paleolithic Tools (left to right): biconical bone Upper Paleolithic Tools (left to right): biconical bone point, Perigordian flint blade, prismatic blade core, point, Perigordian flint blade, prismatic blade core, Soluterean Willow leaf point, double-row barbed Soluterean Willow leaf point, double-row barbed harpoon point (various sites in France)harpoon point (various sites in France)

Page 47: Fossil Hominins: From Australopithecus to Homo

To Sum Up: Representatives of To Sum Up: Representatives of Five SpeciesFive Species

The species:The species: 1. Australopithecus 1. Australopithecus

afarensisafarensis 2. Australopithecus 2. Australopithecus

africanusafricanus 3. Homo habilis3. Homo habilis 4. Homo erectus4. Homo erectus 5. Homo 5. Homo

neanderthalensisneanderthalensis