Modular exaptation: A missing link in the synthesis of artificial form.

•The article shows that exaptations is important in innovation.•We link exaptation and modularity and introduce a model of modular exaptation.•Our model describes three types of exaptations: internal, external and radical.•Exaptive and adaptive innovations are connected in the exaptation/design feedback cycle.•Modularity and exaptation multiply technological options and generate innovation cascades.