Ant-301 Test 3 (Lewis)

The LCA of Pan and Homo lived --- MYA

6-8 MYA

Major Core Adaptive Shifts

1.) Bipedality/ Canine Reduction

2.) Tool Use (Megadontia)

3.) Striding

4.) Symbolism - Art - "Culture"

Taung Child

-Australopithecus africanus

-Found by Raymond Dart

-Dart Claimed it was more human-like than ape-like

-Evidence of Bipedalism

Piltdown Man

-Eoanthropus dawsoni

-Ape-like face, Human-like brain

-HOAX

Mrs. Ples

-Australopithecus africanus Cranium

-Found by Robert Bloom

-Like Chimpanzee (Small brain, Prognathic)

Trend of Head over Evolution

-Size/Robusticity of Facial Skeleton Decreased

-Brain Size Increased

Postcranial evidence found by Bloom

Pelvis & Lumbar spine show functionally significant synapomorphies w/ Homo

Sterkfontein

Australopithecus africanus Cranium Found by Bloom

Australopithecus africanus and Homo Postcranial Similarities

1.) Lumbar Lordosis

2.) Short Ilium

3.) Internally Directed Ilium

Bipedalism Back Adaptations

Lumbar Lordosis Shifts center of Gravity over Feet

Bipedalism Pelvis Adaptations

Lesser Gluteal Muscles:

-Gluteus Medius/Minimus Counteract Pelvic Tilt by pulling on opposite side of lean of body

Quadrupedal Ilia Direction

Dorsoventrally Facing

Bipedal Ilia Direction

Laterally Facing

Quadrupedal Gluteus Gluteus Medius/Minimus Behavior

Extend while walking

Bipedal Gluteus Gluteus Medius/Minimus Behavior

Contract while walking

Function of Laterally Facing Ilia

-Stabilize Hip Joint During Bipedalism

-Only Hamstrings Extend leg at hip joint to go foreword

-Change where Muscles attach to change function

Humans and Apes (Walking)

-Same Bones and Muscles used (Ilium, Gluteal muscles)

-Different Functions during Locomotion

LGM

-Privative Function to extend leg at hip during locomotion

-Modified in Humans/Au. africanus to maintain balance during bipedalism (Derived)

Australopithecus africanus

-Primate-like Cranium

-Bipedal

-Multiple specimens from Multiple S. African Sites (2.3-3.2 MYA)

-Ape Sized Endocranial Volume (ECV)

Subfamily Hominae

Australopithecus africanus ECV

500cc

Modern Human ECV

1400cc

Great Ape ECV

320-560cc

Earliest/Most Privative hominins

Australopithecines

Australopithecines like Homo

-Bipedal

-Thick Enamel

-Canine Reduction

Australopithecines unlike Homo

-Small (ape-sized) brains

-Larger Cheek teeth

Toros-Mennella, Chad

-7-6 MYA

-Ancient Lake Margin of Lake Chad

-Oldest Fossil of new Genus:

Sahelanthropus tchadensis

Sahelanthropus tchadensis

-Massive, Thick Supraorbital torus (Brow Ridge)

-Small ECV: 320cc

-Small Molars

-Unlike other Australopithecines

Why is Sahelanthropus tchadensis a possible hominin?

-Intermediate enamal thinkness (less than Homo, more than apes)

-Intermediate Canine Size w/ apical wear (Blunts tooth)

Ape Dental Features

-Projecting Canines

-Upper Teeth Honed against lower premolar to sharpen

Sahelanthropus

-Found 6-7 MYA

-Found in Toros-Mennella

-Less Prognathic

-Supraorbital Torus different from apes

-Foreword placement of Foramen magnum

-Small Brained Biped w/ slightly reduced canines that act like incisors

-Greater Enamel Thickness

Trait of Other, Non-Human Habitual Bipedal Mammals

Foreword shift of Foramen Magnum (FM)

East African Rift Valley

-East Coast splitting away from rest of continent

-Formed seaways between Africa & Arabia

-Great for Dating Fossils

Ardipithecus

-5.8-4.4 MYA

-Found in Aramis, Ethiopia

Ardipithecus ramidus

-Named in 1994

-Long, Powerful arm

-Enamel Thickness & Canines like Sahelanthropus

-FM Shifted Foreword

-Crushed skeleton found

-Large, Prognathic Facial Skeleton

-Projecting Supraorbital Torus

-Small ECV (~300cc)

-Ape-Like Hands and feet (and Thumbs)

-Bipedal on the ground

Australopithecus atarensis

-3.6-3.0 MYA

-Hader and Laetoli

Laetoli Hominin Trackways

-Very Human-like footprints found

-3.66 MYA

-Probably made by Au. atarensis

-Further evidence of Bipedalism

-Feet had Fully Adducted Hallux

-Differs from Living Apes and Ardipithecus (No Adducted Hallux)

-At least 2 different species (both Bipedal)

Function of Hallux (Big Toe)

-Drives foreword while walking bipedally (Toe-off)

Hader Fossils

-Show Adducted Hallux on Au. afarensis

Au. afarensis

-Bipedal on the ground (From FM)

-Also Climbed trees

-Large Molars/Non-Honing Canines

-Intermediate Cranial Size (~530cc) (Ape-sized)

-Prognathic

-Large/Robust Facial Skeleton

-Typical Australopithecine

Benefits of Bipedalism

-Greater Efficiency

-Endurance Running

-Carrying Things

-Heat Stress

-Seeing over tall Grass

-"Provisioning"

Greater Efficiency of Bipedalism

-Knuckle-walking a good compromise, but is energetically inefficient

-75% Metabolically less costly than Knuckle-Walking

Endurance Running with Bipedalism

-Maximum Running Speed slower than other Mammals

-Lower speed over longer distances

-"Endurance Running Hypothesis"

Carrying Tools with Bipedalism

-Other Anthropoids bipedal when carrying things

-Australopithecus certainty used tools

Reason for Hominin Bipedalism

-No One Knows why

-Still one of the First Major adaptations

African Landscape (5MYA to Present)

Forests Shrunk over time, Grasslands expanded (Makes Terrestrialism more favorable)

Dikika

-Near Hadar in Ethiopia

-3.4 MYA

-Found Cutmarks from stone tools on Bones

Lomekwia (Kenya)

-Tools Found from 3.3 MYA

Lomekwian Tool Industry

-3.3-3.4 MYA

-Used to Butcher Large Animals

-"Flaked" Stone Tools (Cutting edge for sharpness)

-Unknown Which Species made them

-Start of Archeological Record

Oldowan Tool Industry

-Flakes removed with hammer stone, Bashing them together

-Found together with maker

-Made by Hominins with Ape-Sized Brains

-Used to Butcher Animals (Very effective)

Australopithecus garhi

-Large Brow Ridge

-Small Braincase

-Small Canines

-Large Cheek teeth

-Prognathic

Lowis and Mary Leaky

-Worked in Oldural Gorge

-Found Species that made Oldowan Tools

-Found Juvenile Mandible (Not Australopithecine)

-Found 2 Fragmentary Craniums w/ Larger Brains that Australopithecines

-Indicated new Tool Maker: Homo Habilis

Homo Habilis

-Jaws unlike Au.

-Larger Brain than Au.

-Prognathic Jaw

-Possible Extreme Sexual Dimorphism

Prognathic Jaw

Jaw that Juts Foreword

Orthognathic Jaw

Jaw that is level with the rest of the face.

Richard Leakey

-Found Cranial Specimens with facial structure resembling Homo

KNM-ER 1470

-Homo rudolfensis

-Larger Adult ECV

-1.9 MYA

-Found in Koobi Fora, Kenya

KNM-ER 1813

-Homo Habilis

-Smaller Adult ECV

-1.9 MYA

-Found in Koobi Fora, Kenya

Homo Overview

-First Appeared 2.8 MYA

-Evolved from Australopiths

-Multiple Species by 1.9 MYA

-Larger ECV, Orthognathic Craniums, and Different Mandible shape to Australopiths

Koobi Fora Occipital

-1.86 MYA

-Thick, Flexed, Prominant Occipital Torus

-Not H. rudolfensis, nor H. habilis, nor Australopithecine

KNMR-ER 3733

-Homo Erectus

-From Koobi Fora, Kenya

-1.63 MYA

Homo Erectus

-1.63 MYA (Koobi Fora, Kenya)

-Large ECV (850cc)

-Orthognathic

-Larger, Robust Face w/ large Supraorbital Torus

-Larger, Archaic Braincase

-Long Legs

-Tall Stature

-Nearly Human from the Neck down

Archaic Braincase

Braincase Longer than it is tall (Football shaped)

Lake Turkena, Kenya

-1.5-1.6 MYA

-More H. Erectus Found

-"Nariokotome Boy" ("Strapping Youth")

"Nariokotome Boy" ("Strapping Youth")

-H. Erectus

-Found in Lake Turkena, Kenya

-12-15 y.o skull

-ECV ~900cc

-Nearly Complete Skeleton

-5'4" (tall, long legs, no climbing adaptations)

Homo Erectus "firsts"

-Brain size nearly twice that of Australopiths

-Modern structure and limb proportions

-No evidence of climbing adaptations

-fully committed to efficient terrestrial bipedal locomotion

-Good candidate for Human Ancestor

-Migrated out of Africa

Chinese H. Erectus

-Found in Zhoukoutien, China (~500 KYA)

-ECV ~1000cc

-1 Million Years after Nariokatome H. Erectus

-Archaic Braincase

-Large, Robust Facial Skeleton w/ Large Supraorbital Torus

Java H. erectus

-1 MYA

-Found in Java, Indonesia

-ECV ~1000cc

Homo sapiens vs Homo erectus

Sapians:

-Globular Braincase

-Smaller, More Gracile Face

Erectus:

-Archaic Braincase

-Larger, More Robust Face

Homo erectus tools outside of Africa

Oldowan tools, never anything past.

-2.5 MYA-500 KYA (Long Stasis)

Acheulean Industry

-Bifacial "Hand Axes" (Teardrop shape)

-Used for Butchering Large Animals

-Found in Konso Ethiopia (1.75 MYA), Kokiselei Kenya (1.75 MYA), and Olduvai Gorge Tanzania (1.7 MYA)

-Stereotyped Manufacture (All same basic Shape)

-Specialized Differences for different tasks (Picks, Cleavers, etc)

Oldowan and Acheulean Tools

Both:

-Made from Core

-Held in hand (Not hafted)

Difference of Acheulean Tools:

-More steps in Manufacture

-Get more cutting surface from a single core

Stereotyped Manufacture

-Better Materials Used over time

-Refined Manufacturing techniques

-Hand axes kept the same basic shape

Spread of Acheulean Tool Use out of Africa

-Spreads Slowly

-Africa 1.75 MYA

-Middle-East 1.2-1.6 MYA

-India 1-1.5 MYA

-East Asia 800 KYA

-Europe 200 KYA

Harnessing Fire

-Wonderwerk Cave, South Africa

-Acheulean Tools Found

-Ashes of plants and bone fragments (Hearths)

Uses for Fire

-Cooking

-Protection

-Habitat Modification

-Warmth

-Hunting

-Heat Treating Rocks

Tools by 1.0 MYA

-H. Erectus (Africa): new tools and Fire

-H. Erectus (S/SE Asia): No new nothing

Homo heidelberhensis

-350-800 KYA

-Found in Africa, Europe, and West Asia

-Product of Parapatric Speciation with H. Erectus

-Higher ECV (1230-1285cc)

-Archaic Braincase

-Large, Robust Face

Petulone, Greece H. heidelberhensis

-350 KYA

-ECV ~1230cc

-Archaic Braincase

-Large Robust Face

Kabwe, Kenya H. heidelberhensis

-300 KYA

-ECV ~1285cc

-Archaic Braincase

-Large Robust Face

ECV ~800-350 KYA

H. heidelberhensis- ~1200-1300cc

H. erectus - ~1000cc

Modern Humans- ~1400cc

Pleistocene Epoch

-2.6 MYA-12 KYA

-Ends with End of most Recent Ice Age

-Begins with Formation of Permanent Ice caps in the arctic

Pleistocene Process

-2.0-1.0 MYA: Cooling over time

-By 1.0 MYA: Temp fluctuating between warmer Interglacial periods, and Colder Glacial periods (Ice Ages)

-Current world in an Interglacial Period

Coloration between CO2 and Global Temperature

Higher CO2 in Ice, Higher Temperature

(Current CO2 levels way higher than normal)

Conditions Last Time CO2 was this High

-Global Temperature 5-8 Degrees warmer

-Sea levels 17-120ft higher

Why are sea levels lower during Glacial periods?

Water is locked up in ice caps

What do lower sea levels allow?

Allows migration across Continents to what will become islands

Homo floresiensis

-Found in Liang Bau, Flores

-60-100 KYA

-Archaic Cranium

-Fully Bipedal

-Super Small (3.3ft, 55lbs)

-Tiny Brain (ECV=400cc)

-Descended from Trapped H. erectus

Insular Dwarfism

Reduction of animal sizes usually from isolation like an island

Homo Iuzonensis

-Found on Luzon, Philippines

-67-50 KYA

-Slightly smaller than H. florensiensis

Tundra

Area Just under Glacial Ice Sheets

-Extreme Cold, no trees, herds of large game

Homo neanderthalis

-Parapatric speciation of H. erectus

-Well adapted for living in cold enviornments

-Range along southern edge of Eurasian Ice sheet

-Mean Brain Size ~1425cc

-Archaic Cranium

-Huge Nose (Adaption for colder climate)

La Ferrassie, France H. neanderthalis

-72 KYA

-Huge Brain (ECV ~1689cc)

-Archaic Cranium

-Huge Nose (Adaption for colder climate)

Shanidar, Iran H. neanderthalis

-60 KYA

-Midfacial Prognathism

-Short Limbs

-Stocky Body

-Well adapted for cold Eurasian Climate during Ice ages

-More Robust skeleton than modern Humans

Mousterian Industry

-Made From Flakes (not Core)

-Prepared w/ Levallois technique

-Many tools spear pointed

-Active Hunting of Large Game

-Solid evidence for control of Fire

-Evidence for Production of fire