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?