Exam #2 Flashcards
- Over 6 mya first hominids appeared
- About 2.5 mya human line split
- One line developed big molar/premolar teeth for chewing and became extinct about 1 mya
Hominid Evolution
The other line evolved larger brains, smaller teeth, and faces, and started using stone tools.
Robust Australopithecines
A species from the second line evolved into the homo genus, and eventually into our species
Gracile Australopithecines
Anatomically modern humans (_____________) are about 160,000 years old
Homo sapiens sapiens
(all fossils in our species)________, (are old and modern looking) 500,000 years old
Homo Sapiens
All members of our genus Homo
2,000,000 years old
All Hominids regardless of genus
6,000,000 years old
Hominid line split from ape line
5-7 mya
Earliest evidence of hominid:
Sahelanthropus tchadensis at 6;7 mya
Evidence at 5.8-5.2 mya
Ardipithecus ramidus/kadabba
Possible evidence ar 6 mya
Orrorin tugenensis
who appeared 4.2 mya?
first australopithecus appear and is a hominid
2 lines of hominids evolved
3-2.5 mya
- Larger back teeth.
- Only robust in head.
- Thicker and heavily built.
Robust australopithecines (paranthropus)
- Smaller back teeth and jaws .
- Thinner and lighter built head
Gracile australopithecines
First evidence of genus homo
2.5 mya
- Brain is ½ of modern humans.
- Large face and teeth. -Short legs, used stone tools for scavenging animals flesh
- It’s been argued that this species should be reclassified as australopithecus habilis
Homo habilis
The birthplace of modern hominids
Africa
Location of major hominid sites
- Chad
- Ethiopia
- Kenya
- Tanzania
- South africa
7 early hominid species existed prior to 3 mya
- Sahelanthropus tchadensis (6-7 mya)
- Orrorin tugenensis (6 mya)
- Ardipithecus ramidus (5.8-5.2 mya)
- Ardipithecus kadabba (5.6-5.8 mya)
- Australopithecus anamensis (4.2-3.8 mya)
- Australopithecus afarensis (4-3 mya)
- Kenyapithecus platyops (3.5-3.2 mya)
- (only cranial remains so) there is a debate to whether it really was bipedal
- Very small cranium (320-380 cc), same size as chimp
Sahelanthropus tchadensis (6-7 mya)
- Found in 6 mya old sediment
- (probably spent time in trees but also walked)
Orrorin tugenensis (6 mya)
-Had FORAMEN MAGNUM (the large opening at the base of skill where the spinal cord enters) (may reflect bipedalism)
Ardipithecus ramidus (5.8-5.2 mya)
Historically it was believed that bipedalism evolved on the open savannah. However modernly we know that isn’t true. It is now understood that bipedalism evolved in thickly wooded forests.
The savannah hypothesis
- Earliest confirmed well-known hominids
- Confined to africa
- Definitely bipedal
- Multiple species, some living simultaneously
- Relatively small brains (400-500cc)
Australopithecines
- Again, ancestral (ape like) and derived (bipedalism) features are mixed, showing that all these features did not arise at the same time. MOSAIC EVOLUTION (we didn’t start walking after getting a big brain, but we just started using our bodies to walk)
- A. anamensis may be a direct lien to later hominids
Australopithecus anamensis (4.2-3.8 mya)
Discovered “Lucy”
Donald Johnson
- Lucy was one
- Pelvic bones and femur clearly indicated bipedalism
- bipedalism=hominid
- Laetoli footprints
Australopithecus afarensis
These footprints from 3.75 mya shows characteristics associated with bipedalism
Laetoli footprints
A gap between the the teeth (between incisors and canines for primates (A Afarensis)
Diastema
The projection/protrusion of the lower face (A. Afarensis)
Prognastism
- Means “flat faced man from kenya”
- Doesn’t have proganthism
Kenyanthropus platyops
-Robust has very thick looking teeth
-Robust comes after gracile (one of gracile evolved into robust
-The robust’s bigger teeth might be the main reason why they survived better than the gracile.
“Robust” ONLY refers to teeth
The three species of robust australopithecines
Robust australopithecines’ cheek teeth
First species from East africa
-Australopithecus aethiopicus
-Australopithecus (E. Africa)
-Australopithecus boisei
-Australopithecus (S. Africa)
-Australopithecus Robustus
-Australopithecus (S. Africa, Tawny Child, Gracile)
-Australopithecus africanus
-Australopithecus E. Africa, Lucy, Gracile)
-Australopithecus afarensis
Raymond Dart discovered the “Tawny Child”
-Australopithecus africanus
- Initial estimates of age at death 5-7 years.
- However growth incremenents in tooth enamel suggest that the age of death was 3-4 years.
- Matured 20-50% faster than modern humans
Maturation of Australopithecus africanus
Study of how an archeologic site is formed
Taphanomy
Contemporaneous with Australopithecus africanus (-2.5 mya) who lived in South Africa
Australopithecus Garhi
Small= H. Habilis
Large=H. Rudolfensis
Homo/australopithecus habilis
Models for the Origin of Bipedalism
- Tool Use
- Predator Avoidance
- Locomotor Efficiency
- Temperature regulation
- Carrying
- Harvesting
- At least 2.5 may old
- Considered Archeology, NOT paleontology because they are not bones
Stone Tools
3 major stone tool technologies
Oldest to Youngest
- Oldowan
- Acheulean
- Mousteria
One person attempts to create a tool by stting down and hammering at it
Active hammer
A man can just throw a core (rock) which shatters and becomes a tool.
Passive Hammer
- Stone tools leave “V shaped” marks on bone
- Teeth leave “U shaped”marks on bone
- People probably scavaged for meat bc an animal would be first killed by an animal and then the ppl would used stone tools to remove more meat
Marks on bone
-Everything associated with the skull(even teeth)
Cranial material
Made up of cranium+mandible (mandible)
Skull
Ridge on back of skull when neck muscles are attached
Nuchal crest
Attaches chewing muscles
Sagittal crest
Cheekbone
Zygomatic arch
- Ligaments hold bones together
- Tendons attach muscle to bone
- Spine
Postcranial Material
Neck
Cervical vertebrate
Attached to ribs
Thoracic vertebrate
- 2 illia
- 1 Sacrum (tailbone)
Pelvis
- Humerus
- Ulna
- Radius
Arms
Carpals
Wrist
- Metacarpals
- beyond the carpals
Hands
Phalanges
Fingers or toes
- Femur (thigh)
- Tibia
- Fibula
Legs
Tarsals
Ankle
Metatarsals
Foot
-Many Scientist dont believe that homo habilis is a homo, but rather an australopithecus
-1.8 mya homo erectus from asia (derived from ergaster, 1mya) (homo ergaster from africa, is oldersis) large brain, large face, less well rounded skull vs.modern humans
-They left africa for china. 2mya) appeared
-Brain size is ¾ of humans
Was first hominid to leave africa
Brain sized increased 500,000 ya
-First evidence of hominids, similar enough to call homo sapiens (but some call H. heidelbergenHomo erectus
-Some call Non asian ones are h. Ergaster
Originated in africa and was the first member of homo to leave africa
Origin of our genus: Homo
Lived in Africa 2 mya
Homo egaster
Lived in Asia 1 mya
Homo erectus
‘erect walking’ human
Homo erectus
- Eugene dubois found the first h. Erectus.
- Piltdown (HOAX) assumption kept it out the family tree at first
Postcranial skeleton
(strapping youth)was a 12 yr old boy that was really tall
Nariokotome boy
- Diversity of tools increases over time with evolution of h. erg aster/erectus rather than appearing immediately
- First tools similar to oldowan tools, called evolved oldowan
- 1.4 may, a new type of stone tool technology app read called acheulian tradition
- Ergaster used the core while habilis used the flakes that he chipped off from the core
Stone tool tech
First tools similar to oldowan tools
Evolution Oldowan
1.4 may, a new type of stone tool technology appeared
Acheulian tradition
-There are not enough resources to maintain animals so either die
Island biogeographic theory
Refers to early homo sapiens which are not yet anatomically modern in form (anatomically modern homo sapiens;AMHS)
Archaic H. Sapiens
3 types of Archaic H. Sapiens
- H. heidelbergensis- all of the world (asia, africa)
- H. antecessor (west europe)
- H. neanderthalensis (east west europe, middle eas
All of the world (asia, africa)
H. heidelbergensis
West europe
H. antecessor
East west europe, middle east
H. neanderthalensis
We mapped ___ of H. neanderthalensis DNA
65%
We share about ___ with H. neanderthalensis
2%
- Recent discovery, might be added to the list
- Some people have 2% in Russia & 5% in Indonesia
Denovisians
Archaic Homo Sapiens fossils range from 800,00 to 35,000 ya
Distribution of Sites
Reference to proper orientation of a skull
Frankfurt Horizontal (plane)
Projection of the lower face
Prognatism
- African/European H. erectus-like
- 100,000-800,000 ya
H. sapiens heidelbergensis (AHS)
- Very large brain=(1465cc on average)
- Occipital bun=the back of the skull protrudes in Neanderthals
- Midfacial pragmatism=nose is big
- Retromolar space=behind last molar
Neanderthals (archaic)
the back of the skull protrudes in Neanderthals
Occipital bun
nose is big
Midfacial pragmatism
behind last molar
Retromolar space
- Stone tech advanced form the earlier acheulian technology of h. ergster/eretuc and earliest AHS
- Tools known as Mousterian
Neandertal tools
Buried the dead
Neandertals
Concluded that they did have a language but couldn’t make vowel sounds
Lieberman reconstructed anatomy
Shows no difference between AMHS and neandertals
Hyoid bone
A ‘flute’ made from a bear’s femur has been found in a cave in slovenia
Neandertal music
- Skewed their sex ratio
- Caves
Lifeways
160,000 ya anatomically modern humans appear.
- By 28,000 ya all fossils are anatomically modern homo sapiens in form
- AMHS existed before AHS disappeared
- potential for up to 100kya of overlap
Anatomically modern H. sapiens
- Oldest sites fare from South and East Asia and date to between 90 and least 160 kya
- Sites in the middle East date back 92 cya
- AMHS existed before AHS disappeared
- potential for up to 100kya of overlap
Distribution of sites
- Oldest human population
- probably gave rise to all humans
Kung
Two main theories of recent human origins and a third
1) multi regional hypothesis, Regional continuity, Regional coalescence
2) Out of Africa, Mitochondrialeve, Replacement model (hypothesis), Garden of Eden
3) MOSTLY out of Africa Hypothesis, most believed. References to how humans populated the world
