Fossil Hominins From Australopithecus to Homo

Model of Human Evolution: Australopithecus to Homo Australopithecus afarensis to A. africanus : Gracile Australopithecines Paranthropus robustus and boisei: Robust Australopithecines—Dead end? A. africanus to Homo habilis : Rise of tool manufacture? H. habilis to H. erectus: Global spread; increased tool assemblage H. erectus to H. sapiens: Tool specialization and population explosion H. neanderthalensis: Dead end?

Australopithecus afarensis to A. africanus : Gracile Australopithecines

Paranthropus robustus and boisei: Robust Australopithecines—Dead end?

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

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

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

H. neanderthalensis: Dead end?

Fossil Hominins: General Trends Large bulbous cranium Short face compared to ape Vertical carriage of head Hands and Forelimbs Adapted to Tool Making and Use Bipedal Structure of Postcranial Skeleton

Large bulbous cranium

Short face compared to ape

Vertical carriage of head

Hands and Forelimbs Adapted to Tool Making and Use

Bipedal Structure of Postcranial Skeleton

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

A. afarensis: 390-500 cc; av. 440 cc

A. africanus: 435-530 cc; av. 450 cc

A./P robustus: 520 cc, one specimen

A.P. boisei: 500-530 cc; av. 515 cc.

H. habilis: 500-800 cc; av. 680 cc.

H. erectus: 750-1250 cc; av. 1000 cc

Neanderthal: 1300-1750 cc. av: 1450

H. (s.) sapiens: 900-2350 cc. av. 1400

Fossil Trends: Forelimbs and Hands Shortened forelimb Hands (manipulation, not locomotion) Enlarged thumb Straight, noncurved finger Enhanced finger sensitivity

Shortened forelimb

Hands (manipulation, not locomotion)

Enlarged thumb

Straight, noncurved finger

Enhanced finger sensitivity

Fossil Hominins: General Trends--Bipedalism S-shaped vertebrae (backbone) Short, wide, bowl-shaped pelvis Femoral head (ball of femur at pelvis) angled and strengthened Lengthened hindlimb Angle of knee: femur “slopes” to pelvis Platform (arched) structure of foot Nonopposable big toe; toes not curved

S-shaped vertebrae (backbone)

Short, wide, bowl-shaped pelvis

Femoral head (ball of femur at pelvis) angled and strengthened

Lengthened hindlimb

Angle of knee: femur “slopes” to pelvis

Platform (arched) structure of foot

Nonopposable big toe; toes not curved

Lucy ( Australopithecus afarensis ) and Us (Homo sapiens) Note the Following: Shorter (3’6”) Longer arms Curved fingers Shorter lower legs Greater prognathism Sloped forehead Smaller cranial capacity What are the Similarities? Hint: it’s all related to bipedalism

Note the Following:

Shorter (3’6”)

Longer arms

Curved fingers

Shorter lower legs

Greater prognathism

Sloped forehead

Smaller cranial capacity

What are the Similarities?

Hint: it’s all related to bipedalism

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

When We Became Bipedal (According to Gary Larson) “ Hey! Look! No hands!” (Does he look like Lucy to you. . .?)

“ Hey! Look! No hands!”

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

Gracile and Robust Australopithecines For A. africanus (top), note: Somewhat rounder skull No Sagittal crest Prognathous jaw For Paranthropus boisei, note: Sagittal crest (ate a lot of veggies) Massive lower jaw (mandible) Flatter face Massive cheek bones (zygomatic arch)

For A. africanus (top), note:

Somewhat rounder skull

No Sagittal crest

Prognathous jaw

For Paranthropus boisei, note:

Sagittal crest (ate a lot of veggies)

Massive lower jaw (mandible)

Flatter face

Massive cheek bones (zygomatic arch)

Summary of Australopithecines Cranial capacity increased marginally All australopithecines had Sloping foreheads Prominent brow ridges Prognathous lower face and jaws Bipedal postcranial skeletons Robust forms probably were dead ends Graciles likely evolved toward Homo .

Cranial capacity increased marginally

All australopithecines had

Sloping foreheads

Prominent brow ridges

Prognathous lower face and jaws

Bipedal postcranial skeletons

Robust forms probably were dead ends

Graciles likely evolved toward Homo .

Australopithecus and Homo Compared—Frontal View Left: A. africanus Right: H. habilis Note: Different Cranial Capacities Brow Ridge Size

Left: A. africanus

Right: H. habilis

Note:

Different Cranial Capacities

Brow Ridge Size

Australopithecus and Homo Compared—Side View Top: A. africanus Bottom: H. habilis Compare: Mass of Jaws Size of Crania Prognathism

Top: A. africanus

Bottom: H. habilis

Compare:

Mass of Jaws

Size of Crania

Prognathism

Postorbital Constriction Left: Homo erectus Right: Australopithecus africanus Note the narrower constriction of A. africanus’s postorbital constriction than that of H. erectus

Left: Homo erectus

Right: Australopithecus africanus

Note the narrower constriction of A. africanus’s postorbital constriction than that of H. erectus

Homo habilis: The First Known Toolmaker Note the following: Face is much flatter Reduced brow ridge (supraorbital torus) Larger cranial capacity (680 cc.) Toolmaking Technique Hammerstone used to strike A core (lump of stone) to knap A Flake (stone chip) Note: Stone has to be crystalline (so it will fracture predictably)

Note the following:

Face is much flatter

Reduced brow ridge (supraorbital torus)

Larger cranial capacity (680 cc.)

Toolmaking Technique

Hammerstone used to strike

A core (lump of stone) to knap

A Flake (stone chip)

Note: Stone has to be crystalline (so it will fracture predictably)

Homo habilis According to Gary Larson

Australopithecines and Homo Compared I Cranial capacity Australopithecines: 400-530 cc Homo: 500-2300 Maximum braincase width Australopithecines: low on skull Homo: near top Postorbital constriction Australopithecines: marked Homo: moderate to slight

Cranial capacity

Australopithecines: 400-530 cc

Homo: 500-2300

Maximum braincase width

Australopithecines: low on skull

Homo: near top

Postorbital constriction Australopithecines: marked Homo: moderate to slight

Australopithecines and Homo Compared II Supraorbital torus (brow ridge) Australopithecines: large to moderate Homo: large to slight Zygomatic arch Australopithecines: large, flaring Homo: small, not flaring

Supraorbital torus (brow ridge)

Australopithecines: large to moderate

Homo: large to slight

Zygomatic arch

Australopithecines: large, flaring

Homo: small, not flaring

Australopithecines and Homo Compared III Facial size relative to brain case Australopithecines: large Homo: small Jaw A: Massive and prognathic; no chin H: Not massive Prognathism slight to nonexistent; Chin present in sapients Molars and premolars Australopithecines: large; afarensis with diastema Homo: small

Facial size relative to brain case

Australopithecines: large

Homo: small

Jaw

A: Massive and prognathic; no chin

H: Not massive

Prognathism slight to nonexistent;

Chin present in sapients

Molars and premolars

Australopithecines: large; afarensis with diastema

Homo: small

Australopithecines and Homo Habilis Compared: Skulls General trends Encephalization: Cranial capacity increases Dentition: Cheek teeth are reduced Sagittal Crest (where chewing muscles attach) A./P. robustus and boisei: pronounced A. africanus: sagittal keel or absent H. habilis: absent

General trends

Encephalization: Cranial capacity increases

Dentition: Cheek teeth are reduced

Sagittal Crest (where chewing muscles attach)

A./P. robustus and boisei: pronounced

A. africanus: sagittal keel or absent

H. habilis: absent

Australopithecines and Homo Habilis Compared: Skull/Face Braincase A./P. robustus/boisei: less rounded A. africanus: more rounded H. habilis: most rounded of the three Zygomatic arch A./P. robustus/boisei: very pronounced A. africanus: less pronounced H. habilis: far less pronounced than the australopithecines

Braincase

A./P. robustus/boisei: less rounded

A. africanus: more rounded

H. habilis: most rounded of the three

Zygomatic arch

A./P. robustus/boisei: very pronounced

A. africanus: less pronounced

H. habilis: far less pronounced than the australopithecines

Homo habilis: Hands and Feet Hands Curvature of finger bones are apelike, indicate powerful grip (arboreal) Indications of greater manipulative skill Larger blood supply to hand than earlier hominids Evidence of greater nerve supply Feet: existing fragments indicate modern form: Remains lacked toes

Hands

Curvature of finger bones are apelike, indicate powerful grip (arboreal)

Indications of greater manipulative skill

Larger blood supply to hand than earlier hominids

Evidence of greater nerve supply

Feet: existing fragments indicate modern form:

Remains lacked toes

Tool Traditions: Oldowan Named after Olduvai Gorge Among the finds at Olduvai: Side chopper, a core tool Several flake tools, including End scraper Side scraper Burin Utilized flakes of unknown function Belongs to Lower Paleolithic

Named after Olduvai Gorge

Among the finds at Olduvai:

Side chopper, a core tool

Several flake tools, including

End scraper

Side scraper

Burin

Utilized flakes of unknown function

Belongs to Lower Paleolithic

Manufacturing Choppers Procedure Knapper strikes a spherical piece of stone Flake falls off opposite side Tool flipped over and procedure repeated Several blows create a cutting edge Requirements reflect Intelligence Planning and foreknowledge of design Knowledge of breakage pattern of rock Hand-eye coordination

Procedure

Knapper strikes a spherical piece of stone

Flake falls off opposite side

Tool flipped over and procedure repeated

Several blows create a cutting edge

Requirements reflect Intelligence

Planning and foreknowledge of design

Knowledge of breakage pattern of rock

Hand-eye coordination

Oldowan Tradition End chopper Heavy duty scraper Flake scraper Spheroid Hammerstone Chopper Horn core tool or digger

End chopper

Heavy duty scraper

Flake scraper

Spheroid Hammerstone

Chopper

Horn core tool or digger

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

Compared to H. habilis, H erectus had:

Larger brain (1000 cc vs 680 cc average)

Forehead flatter, less sloping

More rounded occipital torus

endocasts indicate hemispheric asymmetry

Homo erectus and Homo sapiens

Homo erectus or ergaster Note: Apelike but larger cranium Postcranial Skeleton Vertebrae: S Shaped Ribcage: Not funnel shaped, now like ours Pelvis: Bowl shaped Angle of Thighbone

Note:

Apelike but larger cranium

Postcranial Skeleton

Vertebrae: S Shaped

Ribcage: Not funnel shaped, now like ours

Pelvis: Bowl shaped

Angle of Thighbone

Homo erectus and Homo Sapiens: Cranium (Braincase) Forehead (Frontal) H. erectus: sloping; low and flat H. sapiens: vertical, indicating frontal lobe Supraorbital torus (brow ridge) H. erectus: prominent--extending as a bar H. sapiens: slight or absent Occipital torus: H. erectus: present H. sapiens: slight or absent

Forehead (Frontal)

H. erectus: sloping; low and flat

H. sapiens: vertical, indicating frontal lobe

Supraorbital torus (brow ridge)

H. erectus: prominent--extending as a bar

H. sapiens: slight or absent

Occipital torus:

H. erectus: present

H. sapiens: slight or absent

Homo erectus and Homo sapiens: Cranium and Face Sagittal keel H. erectus: present; vestige of crest? H. sapiens: slight or absent Postorbital constriction H. erectus: pronounced H. sapiens: slight or nonexistent

Sagittal keel

H. erectus: present; vestige of crest?

H. sapiens: slight or absent

Postorbital constriction

H. erectus: pronounced

H. sapiens: slight or nonexistent

Homo erectus and Homo sapiens: Facial Skeleton Facial skeletion H. erectus: Relatively large, with large orbits and nasal opening H. sapiens: Relatively small, with small orbits and nasal opening Prognathism (jutting jaw) H. erectus: Pronounced H. sapiens: minimal or nonexistent

Facial skeletion

H. erectus: Relatively large, with large orbits and nasal opening

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

Prognathism (jutting jaw)

H. erectus: Pronounced

H. sapiens: minimal or nonexistent

Homo erectus and Homo sapiens skulls Compare: Brow ridges (supraorbital tori) Prognathism Constriction behind eye sockets (postorbital constriction) Presence versus absence of chin

Compare:

Brow ridges (supraorbital tori)

Prognathism

Constriction behind eye sockets (postorbital constriction)

Presence versus absence of chin

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

Named after St. Acheul

Characteristics of Acheulean handaxe

Bifacial: both sides knapped

Symmetrical in breadth

Shaped to a point on one end

The edge is thin and sharp

Broad end is curved, but edge is still sharp

Part of Lower Paleolithic

Acheulean Axe as “Swiss Army Knife”; Abbevillean variation Swiss Army Rock? Sharp tip: used for piercing Thin edge: used for cutting (hide or meat off bone) Broad end: used for chopping or scraping Abbevillean Variation: Bifacial, like the Acheulean Not quite so symmetrical Olduvai specimen: transitional type?

Swiss Army Rock?

Sharp tip: used for piercing

Thin edge: used for cutting (hide or meat off bone)

Broad end: used for chopping or scraping

Abbevillean Variation:

Bifacial, like the Acheulean

Not quite so symmetrical

Olduvai specimen: transitional type?

Manufacturing Acheulean Handaxes A demanding task Symmetrical, finely shaped Dozens of flakes removed, from 25 to 75 Each flake blow must be precisely positioned Core must be turned over again and again to maintain symmetry to keep edge straight All the exterior rind ( cortex ) was removed

A demanding task

Symmetrical, finely shaped

Dozens of flakes removed, from 25 to 75

Each flake blow must be precisely positioned

Core must be turned over again and again

to maintain symmetry

to keep edge straight

All the exterior rind ( cortex ) was removed

Abbevillian and Acheulean Handaxes Left: Abbevillian. Note asymmetry, rough retouch Right: Acheulean. Note symmetry, fine retouch

Left: Abbevillian. Note asymmetry, rough retouch

Right: Acheulean. Note symmetry, fine retouch

Homo heidelbergensis or “Archaic” Homo sapiens Left: Skull. Note heavy brow ridge, prognathism Right: Mandible. Note arc-like dental arcade, absence of diastema, absence of chin

Left: Skull. Note heavy brow ridge, prognathism

Right: Mandible. Note arc-like dental arcade, absence of diastema, absence of chin

Manufacturing Levallois Cores and Flakes Knappers Draw outline of flake on stone module Strikes flake of desired shape Requires knowledge of breakage pattern of rock Prepares rock beforehand to control how rock breaks when struck Ensure right shape (e.g. cutting, perforation, piercing) is struck

Knappers

Draw outline of flake on stone module

Strikes flake of desired shape

Requires knowledge of breakage pattern of rock

Prepares rock beforehand to control how rock breaks when struck

Ensure right shape (e.g. cutting, perforation, piercing) is struck

Levallois Flake and Flaking Technique

Homo neanderthalensis : Skeleton Left: Homo neanderthalensis Right : Homo sapiens Compare Relative thickness of bones Breadth of ribcages Size of skulls

Left: Homo neanderthalensis

Right : Homo sapiens

Compare

Relative thickness of bones

Breadth of ribcages

Size of skulls

Homo neanderthalensis: Cranium Left: H. neanderthalensis : note larger cranial size, occipital bun, prognathism, brow ridge Right : H. sapiens : Note rounded cranium, presence of chin, absence of prognathism and brow ridge

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

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

Mousterian Tradition Positively identified with Neanderhals Le Moustier, France is a Neanderthal site Belongs to Middle Paleolithic More sophisticated than Oldowan or Acheulean, both Lower Paleolithic

Positively identified with Neanderhals

Le Moustier, France is a Neanderthal site

Belongs to Middle Paleolithic

More sophisticated than Oldowan or Acheulean, both Lower Paleolithic

Mousterian Tool Assemblage Sample includes Scrapers, Points, and Handaxes

Sample includes Scrapers, Points, and Handaxes

Upper Paleolithic: The Great Leap Forward? Probably begins about 50,000 BP Primary Attributes Shift from flake tools to blades Subsistence on greater range of animal and plant species Larger sites Increase of bone, antler, ivory, shell, and other materials for tools

Probably begins about 50,000 BP

Primary Attributes

Shift from flake tools to blades

Subsistence on greater range of animal and plant species

Larger sites

Increase of bone, antler, ivory, shell, and other materials for tools

Upper Paleolithic: Associated Attributes Associated Attributes Greater use of “imported” goods: raw materials obtainable only from great distances from inhabited sites which suggests trade More elaborate burials, with grave goods Appearance and elaborate use of symbols and works of art.

Associated Attributes

Greater use of “imported” goods:

raw materials obtainable only from

great distances from inhabited sites

which suggests trade

More elaborate burials, with grave goods

Appearance and elaborate use of symbols and works of art.

Upper Paleolithic: The Blades Blades begin roughly 40,000 Years BP Comparative efficiency Levallois cores may produce 5 flakes Many more blades could be produced from same core--and with longer cutting edge Unlike other traditions, blade traditions are shorter lived Oldowan: from ca.2.5 m. yrs BP Acheulean: from ca 1.9 m. yrs BP

Blades begin roughly 40,000 Years BP

Comparative efficiency

Levallois cores may produce 5 flakes

Many more blades could be produced from same core--and with longer cutting edge

Unlike other traditions, blade traditions are shorter lived

Oldowan: from ca.2.5 m. yrs BP

Acheulean: from ca 1.9 m. yrs BP

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

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

To Sum Up: Representatives of Five Species The species: 1. Australopithecus afarensis 2. Australopithecus africanus 3. Homo habilis 4. Homo erectus 5. Homo neanderthalensis

The species:

1. Australopithecus afarensis

2. Australopithecus africanus

3. Homo habilis

4. Homo erectus

5. Homo neanderthalensis