Relevance of threshold concepts for understanding evolution Kiel University, Germany Supervisor: Prof. Dr. Ute Harms Email:


Evolutionary theory is the integrative framework of modern biology and learning its essential tenets is widely considered a necessary feature of scientific literacy. However, research indicates that teachers and students still struggle with teaching and learning evolution, respectively, and have various alternative conceptions. Current research also displays learning difficulties with those evolutionary concepts that are strongly related to abstract concepts like randomness and probability, so-called threshold concepts. Until now, valid tools that assess students’ understanding of these threshold concepts to examine the relationships to knowledge and to the acceptance of evolution, as well as to investigate the effectiveness of educational strategies to support a conceptual knowledge of threshold concepts are lacking.

Four empirical studies have been conducted as part of this dissertation project. All four studies focus on students’ conceptual knowledge of threshold concepts, particularly on the threshold concepts randomness and probability. Study 1 concentrates on the developmental process of two test instruments to measure students’ conceptual knowledge of randomness and probability in an evolutionary and mathematical context (RaProEvo and RaProMath, respectively). In Study 2, the RaProEvo test was used to examine the effectiveness of the simulation software EvoSketch for teaching and learning random and probabilistic processes in evolution. Findings indicate that EvoSketch simulations are a useful tool for learning and teaching these concepts, particularly for fostering long-term understanding. Study 3 deals with the question to which extent conceptual knowledge of randomness and probability is related to knowledge and to acceptance of evolution. Results reveal moderate to strong relationships, while conceptual knowledge of randomness and probability also serves as explaining factor for knowledge and acceptance of evolution. In Study 4, the effect of item features for students’ use of threshold concepts was investigated. Findings examine that students’ use of threshold concepts in their written evolutionary explanations differs among the three investigated contexts, although no consistent pattern was found. Moreover, fine-grained analyses reveal interesting insights into the different expression of threshold concepts according to item features.

Overall, using qualitative and quantitative methods, the presented dissertation provides new insights into the existing body of work on evolution education by developing a more expansive view of understanding (and accepting) evolution that encompasses aspects of threshold concepts.

Full text available in English:

Fiedler, D. (2018). Relevance of threshold concepts for understanding evolution (Doctoral thesis, Kiel University, Germany).

Available from

Publication related to the dissertation:

Fiedler, D., Sbeglia, G. C., Nehm, R. H., Harms, U. (2019). How strongly does statistical reasoning influence knowledge and acceptance of evolution? Journal of Research in Science Teaching, 1– 24. doi:10.1002/tea.21547

Fiedler, D., Tröbst, S., Großschedl, J., & Harms, U. (2018). EvoSketch: Simple simulations for learning random and probabilistic processes in evolution, and effects of instructional support on learners’ conceptual knowledge. Evolution: Education and Outreach, 11(15), 1–17. doi:10.1186/s12052-018-0089-3

Fiedler, D., Tröbst, S., & Harms, U. (2017). University students’ conceptual knowledge of randomness and probability in the context of evolution and mathematics. CBE–Life Sciences Education, 16, ar38. doi: 10.1187/cbe.16-07-0230

Thesis full reference:

Fiedler, D. (2018). Relevance of threshold concepts for understanding evolution (Doctoral thesis). Kiel, Germany: Kiel University Library. Available from

Doctoral Committee:

Prof. Dr. Ute Harms, Prof. Dr. Ross H. Nehm, Prof. Dr. Hinrich Schulenburg, and Prof. Dr. Mojib Latif (Head of the Committee)


Dr. Daniela Fiedler

Biology Education

Leibniz Institute for Science and Mathematics Education (IPN)

Olshausenstraße 62

24118 Kiel


Tel. (+49) 431 880 3579