Pre-university students’ causal reasoning about plant photosynthesis and reproduction: an exploratory study

Abstract

In order to achieve a satisfactory level of biological literacy, it is fundamental that students develop the competence of providing complex causal explanations about biological phenomena, i.e., being able to explore multiple aspects of causes and effects and their interrelatedness. Previous research indicates that students from primary and lower secondary education causal reasoning is often based on simple linear levels of causation. These young students require special teaching and learning practices to aid them in developing the ability to reason causally about science subjects matter. In the present research, we investigated whether this is also the case considering pre-university biology students. Are upper-secondary students able to provide complex causal explanations about different biological phenomena? To answer this question, we chose a recently learned topic and a topic learned a few years ago, respectively: plants photosynthesis and flowering plants reproduction. Through the medium of individual semi-structured interviews with a series of prompting questions, we have explored the current pre-university students’ causal reasoning status for these two biological processes. The nature of students’ causal explanations for each topic was analyzed based on (1) whether they can reason about all the key mechanisms in the biological phenomena, (2) the type and number of steps that students utilize to explain the physiological processes, (3) which causal agents are employed/missing while students explain the mechanisms, (4) how students perceive and explain the possibility of influential factors causing a different outcome for the biological process. For all these dimensions investigated, our results suggest that pre-university students are not yet able to provide causal explanations about plants photosynthesis and flowering plants reproduction. These findings have implications that might require changes in the formal education.