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UNIT 2
Archaeology and Physical Anthropology – Studying the
Past
Outline
EthicsMethods
Multidisciplinary approach Bone Biology Molecular Anthropology Paleoanthropology
Survey and Excavation Systematic Survey Excavation
Kinds of ArchaeologyDating the Past
Relative Dating Absolute Dating: Radiometric Techniques Absolute Dating: Dendrochronology
Studying the Past
Ethics You can’t study
something because it is interesting or of value to science
Contrasting systems of ethics and values, especially when working outside of your country of origin
Ethics
Physical and archaeological anthropologists work in international teams
In Paeloanthropology (study of hominid, hominin, and human life through the fossil record), physical and archaeologists work together
Ethics
Anthropologists must inform and collaborate with officials in the host country What materials will be used Where will artifacts be stored? Who do different samples belong to?
International movement now advocating on behalf on indigenous and formerly colonized people Some early anthropologists robbed
early peoples of history and bodies Lawsuits against museums by
groups seeking reparations of remains and artifacts are common Peru suing Yale to recover objects
taken in 1912 Images of native Australian fauna
like emu and kangaroo belong to Aboriginal people
Ethics Discussion
Who should own and distribute what?
How can the truth be known?
Should these cultures be allowed to sue for their artifacts back, even when taken so long ago? Why or why not?
STOP – Activity Time
Read the article The Kennewick Conundrum in your groups
Discuss with your groups (and be ready to discuss as a whole)
Who do artifacts belong to?How can you prove it?Where do you draw the line between
scientific study and respect for the long dead?
Ethics
Bad behavior of past anthropologists can put them against local communities Anthropologists rely on the
goodwill of those communities to study
Anthropologists must get informed consent to study Informed consent: agreement
to take part in research after being fully informed about it Must be told how samples will
be collected, used, identified, and potential costs and benefits
Ethics
American Anthropological Association (AAA) says anthropologists should not exploit individuals, groups, animals, or cultural or biological materials
Recognize debt to people whom they work and give back
STOP! – Review Time
What kinds of things must archaeologists consider before studying a place?
Why is it important to have a good relationship with the host country?
Who does the AAA say anthropologists should not harm?
Methods
Physical anthropologists focus on fossil remains and what they tell us about human biology
Archaeologists focus on artifacts and what they tell us about past cultures
Multidisciplinary Approach
Different types of scientists work with anthropologists Physicists and chemists help with
dating Work with the different scientific
fields to reconstruct ancient biology and ways of life
Low tech and high tech tools at sites Small hand held tools Photos, maps, drawings, and
measurements all entered into notebooks and computers
Aerial photos and satellite photos Work with geologists and
geographers to use images to find footpaths, roads, canals, flooding, deforestation
Bone Biology
Bone biology is the study of bones as biological tissue, including its genetics, cell structure, growth, development and decay, and patterns of movement Osteology is study of skeletal
variation and its biological and social causes
Paleopathology is the study of disease and injury in skeletons from archaeological sites
Physical anthropologists work in legal context, assisting coroners, medical examiners, and law enforcement agencies Unknown skeleton found, call
anthropologists to help indentify the body Can tell height, age, and sex of
person
Molecular Anthropology
Uses genetic analysis to assess evolutionary links
Evolutionary distance among living species and dates of most recent common ancestry can be estimated
Use genetic clocks to estimate divergence time among species
Paleoanthropology
Study early hominids and hominins through fossil remains
Teams usually consist of scientists, students, and local workers
Paleontologists and geologists are called in early surveying to predict hominin sites
Survey and Excavation
Excavate – dig through layers of a site
Sites are usually part of larger social systems
Systematic survey Study of settlement
patterns over a large area
Reconstruct settlement patterns
Survey and Excavation
Through excavation, archaeologists recover remains by digging through layers of deposits that make up a site
Layers used to establish relative time order of materials encountered in the dig
Excavation is very resource heavy and expensive Digs not allowed without good
reasonSites must be mapped
before being excavated
STOP! Review Time
What methods did archaeologists use?What is bone biology?What is molecular anthropology?What is the difference between surveying and
excavation?
Dating the Past
Different methods and ways to date fossils with different degrees of precision
Relative dating Establishing a time frame
in relation to other strata or materials
Dating methods based on stratigraphy, the science that examines the ways in which earth sediments cumulate in layers called strata
Absolute Dating: Radiometric Techniques
Fossils also have absolute dating – establishing dates in numbers or ranges of numbers
Several methods Carbon dating
Radiometric technique Measure the amount of
14C in organic material to tell fossil’s date of death Half life is short so less
dependable for specimens older than 40,000 years
Absolute Dating: Radiometric Techniques
Another is Potassium/Argon Half life of 1.3 billion years Older the specimen, more
reliable the dateUranium series dating
Measures fission tracks produced during the decay of radioactive uranium
Thermoluminescence (TL) and electron spin resonance (ESR) Measure electrons
constantly being trapped in rocks and minerals
Absolute Dating: Dendrochronology
Dendrochronoly is tree-ring dating Wide rings during wet years and
narrow during dry Climatic variations produce
distinctive year-by-year patterns Crossdating – process of
matching ring patterns among trees and assigning rings to specific calendar years
Limited to certain tree species Those growing in climates
marked with seasons Trees must come from same
region
Absolute dating techniques
Techniquers Abbreviation Materials Dated
Effective Time Range
Carbon-14 14C Organic material
Up to 40,000 years
Potassium-argon K/A and 40K Volcanic rock Older than 500,000 years
Uranium series 238U Minerals Between 1,000 and 1,000,000 years
Thermoluminescence
TL Rocks and minerals
Between 5,000 and 1,000,000 years
Electron spin resonance
ESR Rocks and minerals
Between 1,000 and 1,000,000 years
Dendrochronology
Dendro Wood and charcoal
Up to 11,000 years
STOP! Review Time
What are the two types of dating methods?What are the different types of absolute
dating methods?