Biologists explain organisms’ behavior not only as having been programmed by genes and shaped by natural selection, but also as the result of an organism’s agency: the capacity to react to environmental changes in goal-driven ways. The use of such ‘agential explanations’ reopens old questions about how justified it is to ascribe agency to entities like bacteria or plants that obviously lack rationality and even a nervous system. Is organismic agency genuinely ‘real’ or is it just a useful fiction? In (...) this paper we focus on two questions: whether agential explanations are to be interpreted ontically, and whether they can be reduced to non-agential explanations (thereby dispensing with agency). The Kantian approach we identify interprets agential explanations non-ontically, yet holds agency to be indispensable. Attributing agency to organisms is not to be taken literally in the way we attribute physical properties such as mass or acceleration, but nor is it a mere heuristic or predictive tool. Rather, it is an inevitable consequence of our own rational capacity: as long as we are rational agents ourselves, we cannot avoid seeing agency in organisms. (shrink)

The goal of this essay is to assess the Selected-Effects Etiological Theory of biological function, according to which a trait has a function F if and only if it has been selected for F. First, I argue that this approach should be understood as describing the paradigm case of functions, rather than as establishing necessary and sufficient conditions for function possession. I contend that, interpreted in this way, the selected-effects approach can explain two central properties of functions and can satisfactorily (...) address some recent counterexamples. This reading, however, shows that there is only a partial overlap between biological functions and selected effects, so the former cannot be reduced to the latter. Finally, I maintain that this result is still compatible with a naturalistic theory of function that appeals to some evolutionary process. (shrink)