Olduvai Gorge
- Olduvai Gorge, Tanzania, one of the most important paleoanthropological sites in world
- Invaluable in furthering understanding of early human evolution
- Homo habilis, probably first early human species occupied Olduvai Gorge, 1.9 mya
- 1.8 mya - Paranthropus boisei
- 1.2 mya - Homo erectus
17,000 years ago - Homo sapiens - Earliest humans, hominins,
- Evidence of scavenging and hunting-highlighted by presence of gnaw marks predate cut marks-and of ratio of meat v plant material
- Collecting of tools and animal remains in central area evidence of social interaction
Tools
- Oldest tools at Olduvai classified as Oldowan, then the Chellean and the Acheulean. Higher still (and later still) are Lavalloisean artifacts, and finally Stillbay implements
Hunters or scavengers?
- Gatherers
Australopithecus Boisei
- Largest of Paranthropus genus (robust australopithecines)
- Lived in East Africa during Pleistocene epoch, from about 2.3 mya until about 1.2 mya
Discovery
- Mary Leakey, 1959
Nutcracker Man
- First hominin to use stone tools
Morphology and Interpretation
- Brain volume small: 500-550 cc
- Shorter foramen magnum
- Sexual dimorphism
- Skull highly specialized for heavy chewing
- Back molar teeth large
- Thickest enamel of any known hominin
- Strong sagittal crest
Behavior
- Developed survival strategy
- Tubers
Temporal fossa
shallow depression on side of skull bounded by temporal lines and terminating below level of zygomatic arch
Zygomatic bone
two facial bones that form cheeks and lateral walls of orbits, commonly referred to as cheekbones
Temporalis muscle
one of the muscles of mastication toward front of cheek
Masseter muscle
one of the muscles of mastication towards rear part of cheek
Sagittal crest
ridge of bone running lengthwise along midline of top of skull (at sagittal suture)
Sexual dimorphism
distinct differences in size or appearance between male and female of same species
Encephalization quotient
A measure of the relative size of the brain of a particular species compared with the expected value for members of the group to which it belongs. It is used to estimate the comparative intelligence of animals, particularly in anthropology.
Olduwan tools
The Oldowan is the oldest-known stone tool industry. Dating as far back as 2.5 million years ago, these tools are a major milestone in human evolutionary history: the earliest evidence of cultural behavior. Homo habilis, an ancestor of Homo sapiens, manufactured Oldowan tools.
- widespread stone tool archaeological industry in prehistory
- these early tools were simple, usually made with one or a few flakes chipped off with another stone
Homo habilis
- First trace of H. habilis, 1955: two hominin teeth (“milk teeth”), difficult to link to taxa unlike permanent teeth
- Short and disproportionately long arms compared to modern humans
- Less protruding face than australopithecines
- New findings in 2007 seemed to confirm that H. habilis and H. erectus coexisted
- 550 cc
- Mastered Lower Paelolithic Olduwan tool set which used stone flakes
Used to butcher and skin animals - Intelligence and social organization more sophisticated
Homo rudolfensis
Extinct species of tribe homini
Dated 1.9 mya
526 cc
Only one good fossil of Homo rudolfensis: KNM-ER 1470
Similarities to H. habilis
Smaller orbits
Projection of mid-face below nose and smaller skull
Olduvai Gorge is located on the edge of which of the following?
The Serengeti
The Shungura Formation is largely made up of river sediments. As a result the fossils found at this site are which of the following?
Poorly preserved
The A.L. 666 maxilla found at Hadar in 1994 resembles Homo in which of the following features?
Rounded dental arch and deep palate
The trend in brain size during hominin evolution is best described as which of the following?
Steady increase for the first 3 million years with a rapid increase over the last 500,000 years
