Hominin
A species on the human branch of the evolutionary tree. Hominins include Homo sapiens and our ancestors, a group of extinct species that are more closely related to us than to chimpanzees.
Mosaic Evolution
Different physiological systems evolve at different rates
Paleoanthropology
The interdisciplinary approach to the study of earlier hominins- their chronology, physical structure, archaeological remains, habitats, and so on.
Taphonomy
The study of what happens to an organism fromt he animal's death through fossilization.
Olduvai Gorge
Over 150 species of extinct fossils have been found here.
Biostratigraphy
Comparison of fossils from undated locality to those of a well dated locality
Flourine dating
Relative amount of flourine from groundwater
Paleomagnetism
Fluctuations in the earth's magnetic field have occasionally caused global polar reversals
Carbon 14 dating
Process of estimating age of once living material by measuring the amount of radioactive isotope of carbon present in material.
Potassium Argon dating
Measures the decomposition of K-40 Argon gas; estimate the ages of the oldest ancestors; Radiometric dating method that established the ages of geological strata and early archaeological sites from volcanic rocks. Used to date prehistory from the earliest
Uranium Lead dating
Based on radioactive decay of 238U into daughter atoms.
Luminescence
Meausting number of radioactive particles trapped in matrix over time
Fission-track dating
Measures spontaneous fission within the atomic nucleus of 238U
Amino acid dating
Compare the ratio of living vs dead amino acid isomers that result from protein breakdown after death
Bipedalism
Precedes brain expansion by more than 2.5 million years and tool use by 2 million. Foramen magnum anteriorly positioned to balance head. Pelvis has become shorter and broader.
Origins of Bipedalism
Human females are unique in order to attract a mate. Still boils down to males becoming bipedal to carry food.
Origins of Bipedalism
Infants had to be born relatively prematurely to adapt to changes in mother's pelvis so mothers had to carry children long and the children could no longer cling to their fur. Still based on carrying.
Origins of Bipedalism
More efficient when walking long distances
Origins of Bipedalism
Ability to see and move around their surroundings better
Homo erectus
The most widespread of all prehistoric hominids, and the most similar to humans. Evolved about 1.8 million years ago and became extinct 70,000 years ago. Means "erect man" - had locking knee joints, larger brains, and more advanced tools. Discovered in Ja
Homo sapiens
The species of bipedal primates to which modern humans belong, characterized by a brain capacity averaging 1400 cc (85 cubic in.) and by dependence upon language and the creation and utilization of complex tools. Evolved 900 thousand years ago.`
Oldowan
The first stone tool industry, beginning between 2.5 and 2.6 million years ago and lasting until 1.4 million years ago.
Acheulean
Subsequent tool industry that featured more detailed stone tools, namely the pear shaped "hand axe" and other scrapers. Associated with Homo erectus. Used from about 1.65 mya to 100,000 years ago.
Late Miocene Africa
Earliest probably hominins (7-5 million years ago) are proved from ancient river and lake margins in Kenya, Ethiopia, and Chad. Later hominins (5-1 million years ago) found elsewhere in east Africa and in caves in south Africa.
Sahelanthropus tchadensis
6-7 million years ago. Found in the Sahel desert of northern Chad. Nuchal area indicated bipedalism. Small braincase with large brow ridges and sagittal crest.
Orrorin tugenensis
6 million years ago. Found in Lake Baringo region, Kenya. Femore indicated bipedalism.
Ardipithecus ramidus
4.4-5.8 million years ago. Found in Middle Awash River, Ethiopia. Brain size similar to chimps but the muzzle is less prognathic. Foramen magnum is anteriorly positioned.
A. anamensis
3.4-4.2 million years ago. Found in East Lake Turkana, Kenya. The first discovered Australopithecine. Large canines and giant teeth for hard food.
A. afarensis
Lucy. 2.9-3.6 million years ago. Found in Ethiopia, Kenya, and Tanzania. Fully bipedal but could not walk upright.
A. garhi
2.5 million years ago. Found in Middle Awash River, Ethiopia. Very ape-liek face and had large front teeth and very large back teeth with powerful muscle markings. Associated with stone tools and cut-marked bone.
A. africanus
2.5-2 million years ago. Found in South Africa. Forward positioned foramen magnu,. Human-like teeth, ape-like projecting face. Taung child.
A. robustus
1.4-2 million years ago. Found in South Africa. Broad, flat face with a very pronounced sagittal crest. Actually least robust of the 3.
A. aethiopicus
2.3-2.7 million years ago. Found in Kenya and Ethiopia. Small brain size with extreme development of cranial cresting. Intermediate between A. afarensis and later P. boisei
A. boisei
1.2-2.3 million years ago. Found in Tanzania and Kenya. Relatively small brains but hyper-robust dentrition.