About This Chapter
Praxis Earth and Space Sciences: Earth History and Life Forms - Chapter Summary
The lessons in this chapter explore the earth's past and the methods scientists use to study it. You can review the geologic time scale, theories of geologic evolution and relative dating principles. Other lessons explore scientific ideas about the origin of life on Earth. These lessons will prepare you to:
- Explain relative dating with fossils as indicators of time
- Recognize the conditions of fossil preservation
- Discuss the history of life on Earth
- Define extinction and mass extinction
You will be guided through these topics by expert instructors who know how to make studying fun. The self-assessment quizzes included with each lesson enable you to test your knowledge. Feel free to watch the video more than once and repeat the quiz!
1. Geologic Time Scale: Major Eons, Eras, Periods and Epochs
The geologic time scale is an essential tool for understanding the history of Earth and the evolution of life. In this lesson, explore the principal eons, eras, periods, and epochs that help us track major events in geologic history.
2. Theories of Geological Evolution: Catastrophism vs Uniformitarianism
Geologists haven't always agreed about the history of our planet. They have debated between catastrophism and uniformitarianism over the last few hundred years! Learn about the two main theories of geologic evolution and how scientists came to resolve the dispute.
3. What is Relative Dating? - Law of Superposition, Principles of Original Horizontality & Cross-Cutting Relationships
Discover how geologists study the layers in sedimentary rock to establish relative age. Learn how inclusions and unconformities can tell us stories about the geologic past. We'll even visit the Grand Canyon to solve the mystery of the Great Unconformity!
4. Relative Dating with Fossils: Index Fossils as Indicators of Time
You may already know how to date a fossil with a rock. But did you know that we can also date a rock with a fossil? Watch this video to find out how we use index fossils to establish the relative ages of rocks.
5. Conditions of Fossil Preservation: Rapid Burial, Hard Parts & the Elements
Learn how fossils are formed and how varying conditions affect the preservation of organisms. What is the best way for a dinosaur to become fossilized? Find out here!
6. The Origin of Life on Earth: Theories and Explanations
Ever wonder how living things came from non-living things? We will explore what conditions on early Earth may have created life from non-living items.
7. The History of Life on Earth: Timeline and Characteristics of Major Eras
The Earth is over 4 billion years old. Ever wonder what happened during certain time periods in that large amount of time? We will look at the major eons and eras of Earth's history along with important characteristics of each.
8. What Is Extinction? - Defining Background and Mass Extinction
In this lesson you'll discover what the term 'extinction' means as well as learn the two different types of extinction: mass extinction and background extinction. You will also discover how humans contribute to extinction events.
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Other chapters within the Praxis Earth & Space Sciences - Content Knowledge (5571): Practice & Study Guide course
- Praxis Earth & Space Sciences: Scientific Research Methods & Tools
- Praxis Earth & Space Sciences: Data Collection & Analysis
- Science Education Safety
- Praxis Earth & Space Sciences: Technology of Ocean & Space Science
- Praxis Earth & Space Sciences: Properties of Matter
- Praxis Earth & Space Sciences: Principles of Energy
- Praxis Earth & Space Sciences: Biological, Physical & Chemical Processes
- Praxis Earth & Space Sciences: Science, Technology & Society
- Praxis Earth & Space Sciences: Energy Sources
- Praxis Earth & Space Sciences: Earth Resources
- Praxis Earth & Space Sciences: Plate Tectonics
- Praxis Earth & Space Sciences: Rock Deformation and Mountain Building
- Praxis Earth & Space Sciences: Earth's Spheres and Internal Structure
- Praxis Earth & Space Sciences: Earthquakes
- Praxis Earth & Space Sciences: Volcanoes
- Praxis Earth & Space Sciences: Minerals and Rocks
- Praxis Earth & Space Sciences: Weathering, Soil & Waste
- Praxis Earth & Space Sciences: Atmosphere & Hydrosphere
- Praxis Earth & Space Sciences: Weather Systems & Meteorology
- Praxis Earth & Space Sciences: Weather and Storms
- Praxis Earth & Space Sciences: Natural Phenomena & the Earth's Climate
- Praxis Earth & Space Sciences: Surface & Groundwater
- Praxis Earth & Space Sciences: Glaciers & Oceans
- Praxis Earth & Space Sciences: Sun-Earth-Moon System
- Praxis Earth & Space Sciences: Earth & the Solar System
- Praxis Earth & Space Sciences: Galaxies & the Universe
- Praxis Earth and Space Sciences: Content Knowledge Flashcards