Key Concepts

[Skip Breadcrumb Navigation]

Ch. 12: Earth's History: A Brief Summary

After reading and studying Ch. 12, you should be able to:

Concept 1: Understand the complex history of the geologic past by using the Geologic Time Scale. List significant geologic, biologic, and special events for each Era, including the largest span of geologic time during the Precambrian Era.

Concept 2: List the principal developments during the Paleozoic Era, including significant geologic, biologic, and special events.

Concept 3: List the principal developments during the Mesozoic Era, including significant geologic, biologic, and special events.

Concept 4: List the principal developments during the Cenozoic Era, including significant geologic, biologic, and special events.

To evaluate and reinforce your understanding of any or all of the Key Concepts, look at the selection bar on the left side of this page. Select and click on the corresponding Concept Quiz or Chapter Test and answer the questions provided.

To take advantage of Web Resources, select and click on

Exploring Key Terms - We will help you search the Internet,

PH Express Links - Our favorite Websites, and

Field Trips - The next best thing to being there!

[Return to the Top of this Page]