Module 6 The Abyss of Time
Explore the chapters to learn the unit 1 content.
Lesson 3.6.2
Lesson 2 - Early Life
Get Focused
The fossil record and the geologic column both give us clues as to early life on the planet. In this lesson we will look at some of these clues.
Consider the following essential questions as you complete Lesson 2:
- What is a fossil ?
- What are strata ?
- Did the Earth always have an oxygen rich atmosphere
Vocabulary
Below is a link to the Science 20 Glossary. Make sure you can identify and define the terms within the glossary that correspond with this lesson.
Â
Â
Read
Read pages 302 - 305 in the Science 20 Textbook. There is a text link below
Self Check
To check your understanding you can try the questions on page 305 of the Science 20 textbook.
Watch and Listen
Video or multimedia content
Â
Reflect and Connect
What organism is credited for the production of the oxygen in Earth's atmosphere ? Based on the number of this type of organism presently on the Earth and the amount of oxygen they produce per year, how many years would it take for these organisms to produce the present oxygen concentration of Earth's atmosphere. Post your calculations to the discussion forum.
Module 6 : Lesson 2 Assignment.
Once you have completed all of the lesson activities for this lesson, you can complete the online assignment.
Lesson Summary
In this lesson we looked at fossils and the evidence used to determine the conditions of previous times on the Earth.
Lesson 3 will look at getting a handle on the time at which various geological and ecological events took place.