Paleoanthropology and Archeology-2 PDF

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Paleoanthropology and Archeology ● What does it really mean to be human? Anthropology - study of humans in all places and all times, present and past CULTURAL ANTHROPOLOGY PHYSICAL ANTHROPOLOGY ARCHAEOLOGY LINGUISTICS Related Fields BIOLOGY EARTH SCIENCES ECOLOGY ●

Cultural Anthropology - Study of contemporary social groups and their institutions and very often involves the study of simpler societies (language, art, religion, kinship, subsistence, (economics), technology, social and political, organization, all observed direct) - Archaeology must infer these social components from material remains (artifact) - Cross - cultural comparisons are made - Ethnohistory focuses on cultures of the recent past

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Physical Anthropology - study of comparative anatomy of apes and humans including the lower primates and fossil hominids Archaeology (subfield of cultural anthropology) - the study of past material culture (artifacts) and associated environmental and residual information to explain the origin, nature and development of past human lifeways - Material remains of past society allow for its reconstruction provide sufficient information to reconstruct activities of the past

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Archaeologist are anthropologist who use specialized techniques to recover the material remains of past cultures - Archeologist may be regarded as anthropologist who study the lifeways of dead societies while cultural anthropologist study living societies Scientific and non-empirical explanations of existence “Truth in science is not absolute but is a matter of probability” - As scientist we are not omniscient, there is always doubt about our explanations in spite of careful and controlled observations As scientist we use deduction and induction to develop theories based on observable phenomenon (empirical data) - Evolution is not considered to be just a theory anymore - Creationism (intelligent design)

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Culture - unique characteristic of human - It is extra-somatic - It is learned and transmitted (not instinctive) - It is symbolic

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Ethology - study of the natural behavior of organisms under natural conditions - We study contemporary human groups to model archeological representations of such cultures this is called ethnographic analogy

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Cultural evolution as explanation of diversity in cultures - Theorists of 19thh century thought that all cultures must inevitably pass through stages of cultural evolution such as savagery .. barbarism .. civilization - A more modern view is multilinear and takes into account the tremendous diversity of cultures worldwide

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Uniformitarianism (as opposed to catastrophism) states that layers of the earth were accumulated as a result of floods, volcanic eruptions, etc - James Hutton 1788 Theory of the Earth came up with uniformitarianism concept stating that the earth was a least 100,000 plus years old and not 6000 - Definition- forces responsible for change today are the same as those that created it in the past

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Stratigraphy = relationship of layers of earth to each other - Involves principle of superposition - For archaeology the concept is adapted from geology based on this concept archaeologist excavate

How do we determine how old sites/artifacts/geological strata are? Chronology - relative and absolute - Relative: event in time relative to another event in sequence - Absolute (chronometric) : event on a calendrical scale numeric ●

Radiometric dating means dating based on radioactive decay of an unstable element within the material being dated

Carbon 14 or Radiocarbon Dating (5,730 year half life) can be calibrated C-14 >>>> N-14 Carbon 14 produced in atmosphere by cosmic radiation radioactive carbon (14) combines with oxygen into CO2 ●

Accelerator Mass Spectrometry (AMS) dates on samples of less than .01 gram of charcoal

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Allows more direct and accurate dating (e.g. charcoal traces on ceramics) rather than more tenuous association, i.e. charcoal found next to item being dating

● Potassium Argon (KAr) 1.3 billion year half-life Unstable isotope K40 - a natural constituent of volcanic materials Over time K40 >>> Ar40 Because of long half life, not possible to date materials younger than 200,000 years old ●

Paleomagnetism/Archaeomagnetism - Based on shift in position of magnetic north over time - Earth's magnetic field is produced by iron core - Shifting, or polar wandering, is a result of movements in earth's crust

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Uranium series dating - Based on measuring radioactivity of short-lived daughter isotopes of uranium (Thorium 230) formed in materials that initially contained only uranium - Materials suitable for U-series dating are found in many prehistoric archaeological sites, and include stalagmitic layer (flowstones) and spring-deposited travertines (calcium carbonate deposits)

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Thermoluminescence T/L - an absolute dating technique used to measure the accumulation of radiation trapped as light energy in crystalline material (heated stone or clay) - Range: up to 500,000 years old - Can be used to date burned flint common an archaeological sites

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Optically stimulated luminescence (OSL) - Measured radiation (from sunlight) trapped in crystalline structures (like quartz and feldspar) - Used for dating geological sediments, ceramics and bricks - Used to date the last exposure to sunlight

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Electron Spin Resonance (ESR) - Dating early hominid sites in South Africa is problematic because there are no volcanic deposits suitable for dating hominid remains - ESR dating used mainly on teeth, measures radiation damage

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The archaeological records -- the compilation of all artifacts, their contexts and associated residue in an integrated unit

Dietary Information: by analyzed C12-C13 ratio in human bone, dietary information can be obtained

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Plants with C13 isotopes when consumed will be absorbed in bone; strontium isotopes are used to trace population ancestry

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Context- association of artifacts among themselves (provenience) within meaningful spatial patterns The archaeological record- the compilation of all artifacts, their contexts and associated residues in all integrated unit Artifacts- are the primary objects or archeological study, but in themselves have little value without context

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Features - Remains that evidence human activity such as hearths, storage pits, post holes from structures, burials, defensive fortifications, shelter elements - Residues: blood, protein, DNA - Wear Patters: observable use wear on lithics (cutting, sawing, scraping, grinding) micro-wear on lithics, butchering marks on bone gnawing patters by carnivores and rodents

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paleoenvironmental Date” used to reconstruct ancient environments Palynology (pollen) Flotation (seed recovery) Faunal analysis (animal bones) Taphonomy: life history of an artifact

Human Osteology: study and comparison of human skeletal remains covering diet, nutrition, evolutionary development, age of specimen, effects of disease, post-mortem damage, cannibalism, evidence of warfare, stress, age, sex, cause of death Archeological Site vs. Fossil Locality --location where evidence of past human activity is found --on archaeological sites, material, both natural and cultural is accumulated Cultural: Refuse, digarded tools and tool making by products, structural materials Natural: floodplain soils, slope soils, wind deposited soils, rock fall in shelters ●

Fossils - those who study fossils are paleontologist, paleoanthropologists, physical anthropologist, archaeologist and geologist - Fossils are preserved in sedimentary rock through physical and chemical processes - The amount of preservation (soft tissues) depends on amount of time that elapsed before organism is covered with sediment - Mineral replacement of bony soft tissue structures ultimately insures preservation of organism in fossil form by essentially turning it into mineral form - Calcium carbonate and silica most common replacement minerals

Preservation of outer form cast occurs with negative impressions of soft bodied organisms leaving imprint in surrounding matrix (clay, sand) - Imprint is covered by sediment, preserving original impression, which becomes mineralized (turned to stone) - This leaves a fossil record of the organism within geological stratum - En entire community of organisms can be fossilized, giving us context for interpreting how these organisms functioned - Same factor that preserves fossil remains also preserve archaeological sites ●

Other factors of preservation of fossil record - Dryness (mummification - extremely cold and or dry) - Archeological remains may be preserved to ca. 20,000 years; fossilization extends this indefinitely

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Analogies are superficial similarities among organisms Homologies are basic similarities among organisms that share a common ancestry Speciation is process of becoming a new species - occur s in geographical and temporal isolation where physical changes occur to distinguish one population from another

Populations, Subspecies (semi-species) and Species ● Population = group of organisms belonging to the same species at any given time ● Sub species or semi species is a group of organisms within a species that has genetically distinctive traits Genetic Drift -- effects of chance events on gene pool of small population or change in gene pool/gene frequency of a population as a result of chance; more common in small populations Founder

Early Primates Primate Origins: What are some of the basic primate characteristics? The order Primates includes humans (genetically similar) Characteristics Include: 1. Grasping hands with opposable thumbs (nails instead of claws except grooming claw) 2. Sensitive pads on end of fingers and toes facilitates grasping 3. Flexible limbs 4. Highly developed vision [stereoscopic color vision except lemurs] Specialized traits of retina and visual cortex of the brain] 5. Larger brains relative to body size than other mammals and haplorhines (tariformes and anthropoids) have larger brains than other primates 6. Slow growth of offspring 7. Single births or very small litters

8. Unique specialization of the basicranium (auditory bulla or bony case protecting underside of the middle and inner ear → the grasping, vision, and flexible limbs are arboreal adaptations Primate dentition; humans are 2-1-2-3, other primates are 2-1-3-3 Arboreal Theory of Primate Evolution Elaboration of visual and tactile sense receptors and their associated control center in the brain caused increased reliance on vision in an arboreal environment induced by a corresponding reduction in olfaction -- ultimately leading to orbital convergence ●

Why did other arboreal animals not follow this pattern? - The environment selects for individuals with vision for use in an arboreal environment - Leaping behavior from branch to branch as visual adaptation of stereoscopic vision Visual Predation Model ● High degree of orbital convergence and prehensile (grasping) abilities in early primates who were adept at hunting insects and eating ripe fruits in fine branches of tree canopy as well as undergrowth ● Origin and radiation of euprimates follows the significant spread and dominance of angiosperms (large fruit types) in the Paleocene - New rich fruit sources on branch ends were a windfall resource for early primates MODERN PRIMATES → Prosimians (means “before apes”) (strepsirrhines) - Distinguished from simians based on the following: Prosimians have: - Smaller brain - Longer muzzle - Un-fused frontal bones - Postorbital bar (not plate as in anthropoids) behind the eyes - No shovel shaped incisors - Un-fused joint between 2 halves of lower jaw - Smaller carotid arteries - Feet with nails on all but one toe 1. Lemurs (Lemuriformes or strepsirhines) - Vary in size from mouse lemurs to indri (one meter in height) - Tree dwelling primates confined primarily to the island of madagascar - Some have di-chromatic (blue and greens) rather than tri-chromatic (greens, blues, and reds) 2. Lorises (lorisidae

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Arboreal and nocturnal (slide 16...