Students often harbor deeply held beliefs about fundamental concepts in biology that are inconsistent with current knowledge. Even after instruction, these misconceptions can continue to create confusion, and may impede future learning.  In a few topics, such as natural selection, there have been many studies on the identification and correction of misconceptions.  In most areas of biology, however, the common misconceptions have yet to be adequately explored. Here we describe our initial efforts to identify common student misconceptions about population genetics, and to measure their prevalence in biology student responses, post-instruction.  We identified misconceptions through literature reviews and semi-structured interviews with biology students.  We used this information to develop a 31-item multiple-choice diagnostic instrument to measure knowledge of, and misconceptions about, topics in population genetics.  The diagnostic instrument was given to students in three introductory courses and two evolutionary biology courses after they had received instruction in population genetics.

Results/Conclusions

We found that although overall performance on the diagnostic instrument was high, performance on questions about several topics, including genetic drift, assortative mating, and application of the Hardy-Weinberg Equation, was lower. The prevalence of student misconceptions varied by topic and course; both introductory and advanced students retained confusions about the meaning of dominance, while fewer advanced students ascribed universal advantage to heterozygotes, or thought that deleterious traits are always quickly purged from populations, than did introductory students.  The results of this study will be used to inform the design of new virtual laboratories in the EvoBeaker suite of computer activities for teaching evolutionary biology.