Ecological communities are seldom, if ever, biological individuals. They lack causal boundaries as the populations that constitute communities are not congruent and rarely have persistent functional roles regulating the communities’ higher-level properties. Instead we should represent ecological communities indexically, by identifying ecological communities via the network of weak causal interactions between populations that unfurl from a starting set of populations. This precisification of ecological communities helps identify how community properties remain invariant, and why they have robust characteristics. This respects the (...) diversity and aggregational nature of these complex systems while still vindicating them as units worthy of investigation. (shrink)

Biodiversity is a key concept in the biological sciences. While it has its origin in conservation biology, it has become useful across multiple biological disciplines as a means to describe biological variation. It remains, however, unclear what particular biological units the concept refers to. There are currently multiple accounts of which biological features constitute biodiversity and how these are to be measured. In this paper, I draw from the species concept debate to argue for a set of desiderata for the (...) concept of “biodiversity” that is both principled and coheres with the concept’s use. Given these desiderata, this concept should be understood as referring to difference quantified in terms of the phylogenetic structure of lineages, also known as the ‘tree of life’. (shrink)

The concept of biodiversity has played a central role within conservation biology over the last thirty years. Precisely how it should be understood, however, is a matter of ongoing debate. In this paper we defend what we call a classic multidimensional conception of biodiversity. We begin by introducing two arguments for eliminating the concept of biodiversity from conservation biology, both of which have been put forward in a recent paper by Santana. The first argument is against the concept’s scientific usefulness. (...) The other is against its value as a target of conservation. We show that neither of these objections is successful against the classic multidimensional conception of biodiversity. Biodiversity thus understood is important from a scientific perspective, because it plays important explanatory roles within contemporary ecology. Moreover, although it does not encompass all valuable features of the natural world, this does not show that we should abandon it as a target of conservation. Instead, biodiversity should be conceived as one of many grounds of value associated with ecosystems. This is consistent with concluding that a central aim of conservationists should be to protect biodiversity. (shrink)

Some critics of invasion biology have argued the invasion of ecosystems by nonindigenous species can create more valuable ecosystems. They consider invaded communities as more valuable because they potentially produce more ecosystem services. To establish that the introduction of nonindigenous species creates more valuable ecosystems, they defend that value is provisioned by ecosystem services. These services are derived from ecosystem productivity, the production and cycling of resources. Ecosystem productivity is a result of biodiversity, which is understood as local species richness. (...) Invasive species increase local species richness and, therefore, increase the conservation value of local ecosystems. These views are disseminating to the public via a series of popular science books. Conservationists must respond to these views, and I outline a method of rejecting such arguments against controlling invasive species. Ecological systems are valuable for more than local productivity and biodiversity is not accurately described by a local species count. (shrink)