Abstract

In opposition to the etiological conception of biological functions, this paper attempts to show that explanations by natural selection, far from justifying functional attributions, presuppose them, and that these attributions may be understood by appealing to a particular specification of the systemic conception of function, that is, the biological conception of function. This paper argues that the etiological conception of function is based on two fundamental errors: confusing the concept of function with the concept of adaptation, and confusing selectional explanations with functional analyses. This explains the inappropriate demand that those analyses include an etiological explanatory content and make possible the distinction between adaptations and exaptations.