Natural selection as an emergent process: instructional implications

Abstract

Student reasoning about cases of natural selection is often plagued by errors that stem from miscategorising selection as a direct, causal process, misunderstanding the role of randomness, and from the intuitive ideas of intentionality, teleology and essentialism. The common thread throughout many of these reasoning errors is a failure to apply ‘population thinking’. Students fail to recognise that natural selection refers to changes in the distribution of certain traits at the population level, the collective, resulting from interactions between individual organisms and their environment at the next lower level in the system. Processes like selection are emergent processes in hierarchical systems, where patterns in a collective are generated by interactions at the lower level. By helping students develop an emergent process schema that enables them to recognise that even random interactions at one level in a system can generate predictable patterns at a higher level, their understanding of natural selection should improve. Some studies have shown this to be an effective approach for teaching other emergent processes. Instructional recommendations based on these studies are presented here, but more research is needed to determine the full extent to which this approach can improve students’ understanding.

Keywords:

• Emergent processes
• evolution
• misconceptions
• natural selection
• systems

Acknowledgements

I am indebted to Douglas Allchin who read an early draft of this paper, and to two anonymous reviewers for their very helpful comments.