PARENT SESSION
Poster Session #47: Education: K-12.
Wednesday, August 7. Presentation from 5:00 PM to 6:30 PM. Exhibit Hall B & C, TCC
156
Ecology students' conception of the "balance of nature".
Zimmerman, Corinne*,1, Cuddington, Kim2, 1 Learning Research and Development Center, Pittsburgh, PA2 Department of Environmental Science & Policy, Davis, CA
ABSTRACT- Educational studies indicate that students' understanding of scientific concepts are often based on prior conceptions and can be resistant to change. The "balance of nature" concept has been used to explain the functioning of natural systems from ancient times and continues to be invoked in popular culture. Anecdotal results indicate that undergraduates' beliefs about "balance of nature" and its relation to the functioning of real ecological systems remain unchanged even under explicit instructional conditions. We conducted a survey to document how pervasive and robust this idea is among undergraduate science majors. Our results document the pre-instruction conceptions that students hold. We focus on three main findings: (a) Students overwhelmingly believed in the balance of nature concept. Fifty-two percent had a strong belief, 33 percent held a moderate belief, and only 15 percent were skeptical that ecological systems achieve a balance. Students used terms like "equilibrium", "homeostasis", and "stability" to describe the functioning of natural systems, the interactions among species, and population growth rates. (b) Students believed that balance is inherent to nature, rather than being the result of some specific mechanism or biological interaction. The natural establishment of balance was often characterized as the result of an absence of outside factors. (c) Students believed in a clear distinction between the effects of human and non-human factors. For example, they believed that the predator-prey relationship is both balanced and beneficial for both species, and unlikely to lead to extinctions, whereas human hunting and harvesting was more likely to lead to prey extinctions. In the face of such commonly-held beliefs, university educators need to use instructional techniques specifically designed to counter preconceptions about ecological systems. Studies of the efficacy of various instructional manipulations are currently underway.
KEY WORDS: education, balance of nature, undergraduate students, preconception