1. Cite an example of a catastrophic event linked to a mass extinction. 2. Describe the types of evidence that were used to develop the geologic time scale.

3. Explain how geographic isolation can affect evolution. give an example.

4. Summarize the relationship among fossils, rock layers, and the divisions of the geologic time scale.

5. Defend, You tell someone that Earth has evolved over time due to natural process. They question the evidence behind that statement. Compose an argument to convince that skeptical person.