THE GREAT DIVIDE: EFFECT OF INSTRUCTIONAL PRACTICE ON EVOLUTION UNDERSTANDING IN HIGH SCHOOL AND COLLEGE

In both the high school and college curriculum, evolution is a core concept. It is essential to student success in biology and geology, providing students with an understanding of the natural world. Little research exists examining the change in evolution understanding due to various teaching practices. Even fewer studies have compared methods and curriculums of high school to college. Using a modified Bishop and Anderson Open-Response Instrument (ORI) prompt, we investigated how high school biology and university-level introductory geology students describe animal evolution by natural selection. The ORI is frequently used to determine natural selection content knowledge. Students enrolled in a high school biology course (n=74) with evolution as a major unit or an introductory geology class for non-majors (n=77) that included evolution as a topic, were administered a pre- and post-instructional assessment. We analyzed results from one high school biology instructor and two geology instructors. Student-constructed responses to a trait gain or trait loss prompt were coded using a modified Bishop and Anderson coding rubric for the presence and correctness of five key characteristics of natural selection (phenotypic variation, origin of variation, inheritance, fitness, and population change over time).

The ORI scores were low for both pre- and post-assessments for both populations (high school pre = 15.5%, post = 15.8%; college pre = 13.4%, post = 16%). Student performance on both the pre- (p = 0.63) and post-assessments (p = 0.59) was independent of education level. The college students from one instructor performed significantly higher on the pre-assessment (p = 0.04). Education level and instructor were not predictors of the student’s score on the post-assessment. This may show that college students are slightly more prepared for an open-response exam, or may draw on their memories of the theory of evolution from high school. These results indicate that students do not make a shift in their understanding of evolution from high school to college and that more work needs to be done to improve evolution curriculum to ensure that students leave these classrooms with a more robust knowledge of evolution.