Keywords and concepts in structuralist and functionalist biology

All biologists have a ‘way of seeing’ their science which is either explicitly recognised or tacitly held. Our analysis of keywords in biology reveals a major schism between two such systems of thought—functionalism and structuralism. We discuss the keywords “function” and “adaptation” and consider the nature of a functionalist perspective of the organism and its environment, by reference to the touchstone example of industrial melanism. Structuralism—the doctrine that structure rather than function is important—utilises a quite distinct field of keywords to that used in functionalism. Structuralism attempts to explain the generation of actual structures from the range of the possible alternatives and, we suggest, can also explain stability in terms of the organisation of structures themselves. Functionalism may generate knowledge, but it is neither a descriptive knowledge, nor one which is based on an understanding of natural kinds. In contrast, structuralism aims to discover reality. Conceptual and linguistic reforms in evolutionary biology are possible only when we acknowledge the incommensurability of these viewpoints and explicate their tacit components.