Dorothy Fragaszy | A Biological Theory of Tooling
Although using tools is a central feature of human biology, the lack of biologically-grounded theory in this domain limits our ability to study the phenomenon to relate it to human evolution. To begin to fill this gap, I present a theory of tooling applicable to individuals of all species. The theory draws on (a) ecological (perception–action) theory in psychology, that links an animal’s behavior to its perception of affordances, (b) psychological theories about how animals perceive space and move themselves in space, and (c) the biomechanical approach to the study of body movement and the development of coordination of movement. Tooling theory supports testable hypotheses concerning a) the forms of tooling present in diverse taxa with varying perceptual and motor systems and bodies, b) the effects of specific environmental, individual, and task features on a specific performance, and c) the development of tooling. The determination that an action is or is not tooling has no bearing on a judgment about the intellect of the tooler. Instead, a classification of an action as tooling determines the analytical strategy one can take to examine the action. I apply the theory to wild bearded capuchin monkeys cracking nuts with stone hammers and anvils.