I develop an account of ecological role functions—the functions of species within ecosystems—which is informed by alternative regime phenomena in ecology. My account is a causal-role theory which includes a counterfactual sensitivity condition. The account tracks and explains a distinction ecologists make between functions and various activities which are not functions. My counterfactual sensitivity condition resolves the liberality problem often attributed to causal-role theories of function, while also illuminating the explanatory centrality of role functions within ecology.

This paper addresses the stalemate on the question whether biodiversity has intrinsic value. I distinguish between a “weak” conception and two “strong” conceptions of intrinsic value in the environmental ethics literature. The strong conceptions of intrinsic value are connected, respectively, to moral standing and to a strongly objectivist account of value. Neither of these forms of value likely applies to biodiversity. However, the weak conception of intrinsic value is neutral about both moral standing and the nature of value and plausibly (...) applies to biodiversity. In addition, weak intrinsic value avoids common objections to the claim that biodiversity is intrinsically valuable. I develop a cumulative argument showing that environmentalists should presume that biodiversity has intrinsic value in the weak sense. (shrink)