1. Learning Intention: 8.ESS2.1
Science
8th Grade
Notes: Standard 16
Learning Intention: 8.ESS2.1
Analyze and interpret data to support the assertion that rapid or gradual geographic changes lead to drastic population changes and extinction events.
Terms/phrases to Investigate
geographic changes, population changes, extinction events
Crosscutting Concepts
Patterns, Cause and Effect, Stability and Change
Success Criteria/I Can Statement
By the end of this unit I will be able to say...
...I can explain how geological changes can effect populations
and/or cause extinctions.

2. Phenomenon What caused these extinctions?
Get into groups. Maybe do some online research. Discuss.
Geologic Periods
There have been (at least) five major extinction events in our planet’s history.
1) Ordovician-Silurian Event (439 million yrs ago)
---approx. 86% of all life on Earth went extinct. 5
2) Devonian Event (364 million yrs ago)
---approx. 75% of all life on Earth went extinct 4
3) Permian-Triassic Event (250 million yrs ago)
---approx. 96% of all life on Earth went extinct 3 2
4) Triassic-Jurassic Event (210 million yrs ago)
---approx. 50% of all life on Earth went extinct 1
5) Cretaceous-Paleogen event (65 million yrs ago)
---approx. 76% of all life on Earth went extinct