Chapter 8 Fossils Flashcards
What are fossils? What do fossils tell us about the past? What methods do anthropologists and other scientists use to study fossils?
Fossils
remains of once living organisms
Most common types of fossils
bones and teeth
Limitations of fossil analysis
Variations in preservation, accuracy in dating techniques, and the vast scale of time under study
Taphonomy
The study of how bones and other materials came to be buried in the earth and preserved as fossils.
The study of what happens to an organism’s remains after death.
Primary Context
The setting in which the archaeological fossil was originally deposited.
Secondary Context
One to which it has been moved (rivers etc)
Relative Dating Methods
Older or younger than other fossils
Law of Superposition
The lower layer of dirt is older than dirt on top.
Charles Lyell 1830
Law of Association
Objects found in the same archaeological layer under conditions where it is clear that they were deposited at the same time, must all date from the same time.
Absolute Dating Description
Determined through methods that result in a numerical time scale.
Radiocarbon Dating
Method
Based on regular decay of a radioactive isotope of carbon.
Radiocarbon Dating
Range:
300-50,000 Years Ago
Radiocarbon Dating
Application
Organic matter- small sample sizes
Radiocarbon Dating
Did you know?
Most common radiometric dating technique for <50,000 years.
Potassium-argon Dating
Method
Uses the rate at which radioactive potassium, found in volcanic rock, decays into stable argon gas.
