STUDENT INSTRUCTIONS

Work in groups of four. One person should facilitate the discussion (keep it moving, make sure everyone understands), another should ask probing questions (the skeptic), a third should write down your comments and questions (the recorder), and the fourth should report out to the class as a whole (the reporter). Decide who will have the roles of facilitator, skeptic, recorder, and reporter. Then examine the figures and discuss the following questions.

Figure 4A depicts the percent of U.S. acreage planted with Roundup Ready soybeans between 1996 and 2000. Why do you think it was adopted so fast? What implications might this have for regulatory policies? Discuss long-term but unforeseen impacts of this rapid adoption.

Now examine Figure 4B. During the same period of time that the percentage of acreage devoted to herbicide-tolerant soybeans increased (Fig. 4A), what is the pattern of change for herbicide use on soybean fields? Be sure to compare pounds of herbicide applied versus acres. How might you explain the pattern you see here?

Finally, examine and interpret Figure 4C. In this figure, 100% means that the yield of genetically modified soybeans is the same as that of unmodified ones; a value above 100% indicates that yield of Round-up Ready soybeans is higher. How do you compare the effectiveness of the Roundup Ready variety of soybeans with conventional varieties? Why might some states have experienced declines in yield performance? What is the significance of the overall average? What additional information about how the data were collected would help you address these questions with more confidence?