Skills and concepts that students must have mastered
Basic evolutionary theory
Navigating the World Wide Web
Working in groups and presenting their conclusions in an in class discussion format.
How the activity is situated in the course
Content/concepts goals for this activity
Weathering Rate on Land
Nutrient Flux to the Oceans
Burial of Organic Matter
CO2 levels in the Atmosphere and corresponding climatic changes.
Higher order thinking skills goals for this activity
Other skills goals for this activity
Description of the activity/assignment
After completing the attached exercise the students participate in a guided discussion. There are several way to divide students up into groups.
Different groups are asked to summarize: the link between the spread of land plants and
1) atmospheric carbon levels and climatic conditions,
2) organic carbon and dissolved oxygen levels in the ocean
3) the abundance of corals and other marine animals: shallow vs. deep ocean
4) Erosion rates on land and rates of organic matter burial in the oceans.
5) General patterns in diversity and biomass of marine and terrestrial fauna
Then each group is asked to discuss how the aspect they considered about the Devonian Extinction fits into and differs from conditions we see in the modern carbon cycle.
Determining whether students have met the goals
A variation: Students could be asked to draw a concept sketch of how the carbon cycle changed in the late Devonian and compare this with a concept sketch of how the modern carbon cycle is changing.
Aspects they should consider =
Devonian-biomass of living plants (e.g., Evolution of forest ecosystems in the Devonian vs. Deforestation)
Organic carbon burial rates, erosion rates, nutrient flux to oceans and shallow marine turbidity levels
Carbon Dioxide levels and oxygen levels in the ocean, atmosphere
Effects of changing terrestrial biomass levels on climate (both temperature and rainfall patterns)
Diversity of marine and terrestrial fauna
Teaching materials and tips
- Activity Description/Assignment:How the Evolution of Land Plants Changed the World (Microsoft Word 42kB Jun4 09)
- Instructors Notes:
- Solution Set:
"Earth Through Time" by H. Levin