TEACHING ALL VOLUMES SUBMIT WORK SEARCH TIEE
VOLUME 6: Table of Contents TEACHING ISSUES AND EXPERIMENTS IN ECOLOGY
ISSUES: FIGURE SETS

Figure Set 3: Causes of intense elk browsing on cottonwoods and willows during the 20th century.

Purpose: To practice interpreting graphical data; to use the data to address the question of why browsing by elk in Yellowstone was so intense during the 20th century.
Teaching Approach: “Pairs share”
Cognitive Skills: (see Bloom's Taxonomy) — knowledge, comprehension, interpretation
Student Assessment: minute paper or essay quiz

STUDENT INSTRUCTIONS

Now that you have seen the data in Figure sets 1 and 2, you are ready to address the following question: "Why was elk browsing on cottonwoods and willows so intense during much of the 20th century in Yellowstone National Park?" Using your hypothesis from the last exercise, can you make predictions about the population dynamics of the elk herds in and around Yellowstone during this time? Were they most likely growing, declining, or relatively constant, and why? Write down your predictions, and then with your partner examine the data presented in Figure 3. Were your predictions upheld, or not? Why?

Be prepared to discuss your impressions and conclusions with the rest of the class.

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