Digging Up the Past:

Paleoanthropology and Archaeology

Lecture Objectives

Identify the importance of fossil in understanding the behavior and anatomy of ancient hominins.

Identify the differences between paleoanthropology and archaeology.

Compare the similarities and differences between relative and chronometric dating.

Be able to identify and describes examples of relative and chronometric dating.

Paleoanthropology and Fossils

PaleoanthropologyBiological anthropology focus: study of

earlier hominids, including 1. 2. 3. 4.

Highly _____________

What do paleoanthropologists examine?

FOSSILS Remember Cuvier –

he recognized that fossils were once living organisms

BUT fossils were not important in the realm of science until William Smith (engineering surveyor)

Why Fossils? What information do they hold?

Provide direct ______________

Study of fossil centered on two factors Time

Environment

Taphonomy & FossilizationCommonly bones

and teeth sources (comprise 99 % of fossil record)

Taphonomy 1. 2.

Dating Methods

Dating – Why Bother?

Placing sites and fossils into a time frame

Dating techniques Relative Dating Chronometric Dating (numerical dating) What is

the numerical age? Isotope Dating rate at which various ___________

_____________________________________

Relative Dating

Tells the paleoanthropology that something is older or younger than something else

Does provide: 1. 2.

Does not provide: 1. 2.

Relative Dating #1: Stratigraphy

Study of __________________________ Variety of locations can be compared via chemical,

physical and other properties

Law of _______________ Lower stratum (layer) is older than a higher stratum

Problems Earth distributions Length of time to accumulate stratum

Relative Dating #2: Biostratigraphy

Employs the associations of fossils in strata to determine each _________________

Aim is ________________ Why?

Demonstrates that a particular geological section in one location represents the _______________ as another geological section at some other section

Relative Dating #2: Biostratigraphy

Index Fossils – _____________________Example of Irish Elk (died out: 10,600 yBP in

Europe)

Relative Dating #2: SeriationTypological sequences of artifacts

Assumption: ___________________ Frequency of co-occurrence of artifacts in

specific contexts_____________________Indicator of ____________________

Relative Dating #2: SeriationExample:

Contextual seriation Pottery --

style rather than function

Numerical Dating

Dating technique that gives an estimate in actual numbers of years _______________________

We will cover both isotopic and non-isotopic methods: Radiocarbon Radiopotassium Argon-Argon

Numerical Dating #1: Radiometric

Carbon isotopes: Ratio of 14C to 12C is measured

Baseline for start of clock – death of organism By calculating the ratio of 14C to 12C one can

determine ______________________________

Used for material younger than 50,000 – not the best for primate and human evolutionArchaeologists NOT __________________

Numerical Dating #2: Radiopotassium

Non-organic material (e.g. igneous (volcanic) rock)

40K decays slowly from its unstable form to a stable gas, 40Ar __________________________

Dates material older than _________________

Note – cannot date sedimentary rock

First used at ____________________

Numerical Dating #3: Argon-Argon

40Ar – 39Ar: volcanic rock is bombarded with “fast” neutrons in a nuclear reactor

Advantage: ______________________________

• Example: ______________________

Numerical Dating #3: Argon-Argon