The Differing Perceptions of Teachers & Students regarding Teachers' Emphasis on Evolution in High School Biology Classrooms

Article excerpt

In 1973, Theodosius Dobzhansky--one of the leading contributors to the Neo-Darwinian Synthesis--wrote in The American Biology Teacher that "... nothing in biology makes sense except in the light of evolution" (Dobzhansky, 1973). Since then, a variety of scientific professional societies and science-education reforms have stressed the importance of teaching evolution in public schools. For example, the National Association of Biology Teachers (NABT) has declared that "Teaching biology in an effective and scientifically honest manner requires classroom discussions and laboratory experiences on evolution" (NABT, 2002), and the National Academy of Sciences (NAS) encourages biology teachers "... to use evolution as the organizing theme in teaching biology" (NAS, 1998). Most biology teachers I've talked with claim that they comply with these guidelines; that is, they report that they emphasize evolution in their classrooms. However, for several years students in my introductory biology classes have scored disproportionately lower on evolution-related questions on a first-day-of-class exam than they do on questions about other biological topics. If teachers are, in fact, emphasizing evolution in their classes, why do so many entering freshmen know so little about the subject?

I tried to answer this question by surveying Minnesota high school students and teachers about the teaching of evolution. Evolution should be taught effectively in Minnesota. Indeed, the Minnesota K-12 Framework for Science (2003), which Lerner (2000) evaluated as "good," states that "The focus of instruction in life science for all students at the high school level is on developing an understanding of cell structure and function, the relationship of matter and energy in biological systems, heredity, biological evolution, the behavior and interdependence of organisms and apply their understandings in a variety of situations" (p. 3192). The Framework also includes the National Science Education Standards (which discuss natural selection, similarities among organisms, common descent, and the age of Earth; National Research Council, 1996) and a curriculum entitled Life Sciences on Location 9-12 that includes natural selection and competition (p. 3-193). Similarly, Minnesota's Graduation Standards--High School Level require that all high school graduates "... understand biological change over time," including biodiversity and natural selection (p. 3-199). Minnesota's evolution-education standards are supported by the Minnesota Science Teachers Association, whose Board of Directors endorsed the position statement of the NABT (see above) and National Science Teachers Association (National Science Teachers Association, 2004). Clearly, there is strong and consistent administrative support for the teaching of evolution in biology classes of Minnesota's public schools. Creationism (e.g., "intelligent design") is explicitly rejected by the Minnesota Science Teachers Association and NABT, and is not included in Minnesota's science-education standards.

In this study I tried to answer several questions related to these issues. For example, do high school biology teachers claim that they emphasize evolution in their classes? If so, to what extent? Do students agree? That is, do students believe that their biology teachers emphasize evolution? If so, to what extent?

Methods

Surveying Teachers

I used the survey shown in Table 1 to understand teachers' and students' views of the teaching of evolution in Minnesota's public schools. To avoid the low return rates that have typified many evolution-related surveys (e.g., 29% in Ohio; see Zimmerman, 1987), I surveyed 107 randomly-selected Minnesota biology teachers who attended 1) the National Science Teachers Association convention held in Minneapolis, MN from October 30 through November 2, 2003, and 2) the Tenth Annual Biology-Life Sciences Teachers Conference held in St. Paul, MN on December 12, 2003. …