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selective pressures that promote resistance development. This cannot be done blindly, however. Gould showed how one can create models of how resistance might develop in a population of insects, monitor the pests to detect signs of such incipient resistance, and use the model and the monitoring to plan refugia accordingly. Without such careful management, the fields could end up inhabited by insects that are not susceptible to Bt toxin.

Ideally, monitoring should be designed so that it can detect both unexpected and unpredicted events and events that are expected. To illustrate her point, Kapuscinski described how attempts to rebuild self-reproducing salmon populations in the Pacific Northwest backfired when carefully planned spawning interventions resulted in a decrease rather than an increase, in salmon abundance. She summed up this way: “If I were to state in one sentence the primary implications of all these carefully examined cases of failures in living-resources management, I would say that the responsible institutions and users were blind-sided by surprising feedback from the system or, to use the terminology of Sengue, ‘fixes that backfire.' So, if you remember nothing else from what I spoke about today, it should be that we should be prepared for ecological surprise. We should expect ecological surprise." Another reference to unexpected results came from Guenther Stotsky, of New York University, who reported that Bt corn decomposes more slowly than non-Bt corn (probably because it has higher lignin content). His research showed that Bt toxins can remain active in the soil for several months—not an expected result. Despite our lack of knowledge about the ecological implications of these findings, they underscore the importance of being prepared for the unexpected.



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