A community, for ecologists, is a unit for discussing collections of organisms. It refers to collections of populations, which consist (by definition) of individuals of a single species. This is straightforward. But communities are unusual kinds of objects, if they are objects at all. They are collections consisting of other diverse, scattered, partly-autonomous, dynamic entities (that is, animals, plants, and other organisms). They often lack obvious boundaries or stable memberships, as their constituent populations not only change but also move in (...) and out of areas, and in and out of relationships with other populations. Familiar objects have identifiable boundaries, for example, and if communities do not, maybe they are not objects. Maybe they do not exist at all. The question this possibility suggests, of what criteria there might be for identifying communities, and for determining whether such communities exist at all, has long been discussed by ecologists. This essay addresses this question as it has recently been taken up by philosophers of science, by examining answers to it which appeared a century ago and which have framed the continuing discussion. (shrink)

The complexity and heterogeneity of causes influencing ecology’s domain challenge its capacity to generate a general theory without exceptions, raising the question of whether ecology is capable, even in principle, of achieving the sort of theoretical success enjoyed by physics. Weber has argued that competition theory built around the Competitive Exclusion Principle (especially Tilman’s resource-competition model) offers an example of ecology identifying a law-like causal regularity. However, I suggest that as Weber presents it, the CEP is not yet a causal (...) regularity. Instead, I argue that the scientific understanding in Tilman’s theory takes a different form. The theory explains through a structure I call “channeling explanation” which does not depend on deduction from general laws, but rather builds on constraints and trade-offs represented in state-space. Recognizing this structure supports the more general point that ecology and other so-called special sciences can reveal novel theoretical approaches to philosophy of science when approached with openness to their uniqueness. (shrink)

Although ecological theory has historically focused on negative interactions among populations, like competition and predation, ecologists and conservation biologists highlight the significance of interdependence. It is not clear, however, what is asserted in the causal hypothesis that one population is interdependent on others. This essay argues that the most informative causal regularities for representing dependencies are those connecting populations through environmental constraint variables. Interdependence among populations can thus be understood as constraint-mediated dependency relations connected in a circuit.

Morar et al. argue that justifications for conservation based on assessments of biodiversity are vacuous, because ‘biodiversity’ is a flawed concept. However, their analysis of the concept mistakes how scientific concepts function. The concept ‘biodiversity’ stands up to their criticisms.

The problem of ceteris paribus clauses and Hempel’s problem of provisos are closely-related difficulties. Both challenge advocates of accounts of scientific theories involving laws understood as universal generalizations, and they have been treated as identical problems. Earman and Roberts argue that the problems are distinct. Towards arguing against them, I characterize the relationship between Hempel’s provisos and one way of expressing ceteris paribus clauses. I then describe the relationship between the problems attributed to the clauses, suggesting that they form a (...) single problem-cluster. However, Hempel’s way of formulating provisos and discussing what they involve entangles provisos with the problem of skepticism. This creates a departure in Hempel’s discussion of provisos from the distinctive problem of vacuity which characterizes the problem of ceteris paribus clauses, though for different reasons than Earman and Roberts suggest. (shrink)