Learning Evolution – A Longterm Case-Study with a Focus on Variation and Change

The theory of evolution is the central backbone of biology and essential to the understanding of biological phenomena. Various studies in biology education have pointed out specific student conceptions which hinder understanding of evolution. However, long-term studies about the development of conceptions central to the theory of evolution (e.g. variation and change) are still missing. To fill this gap, this study documents the conceptual reconstruction of three students from grades 8 to 12 (end of lower secondary level up to final examination in Austria). During this period, these students participated in teaching sequences about evolution, which were designed to address students’ conceptions. Using a case study approach, data was collected via repeated pre- and post-interviews in grades 8, 10 and 12 before and after the teaching sequences. Using qualitative analysis, we identified the students’ conceptual understanding of fundamental evolutionary concepts like ‘variation’ and ‘change’. The results show that while students’ understandings develop from everyday conceptions to more scientific ones over the years, many of their ontological models or naïve ideas remain unchanged. Teleological, essentialist and anthropomorphic thinking continues to underpin the learning and results in mixed conceptions e.g. goal-oriented mating or dichotomous thinking about variation and traits. In addition, student concepts remained poorly integrated; therefore, we conclude that evolution education has to consider ontological models and deep conceptual development.