This book is a sustained examination of issues in the philosophy of ecology that have been a source of controversy since the emergence of ecology as an explicit scientific discipline. The controversies revolve around the idea of a balance of nature, the possibility of general ecological knowledge and the role of model-building in ecology. The Science of the Struggle for Existence is also a detailed treatment of these issues that incorporates both a comprehensive investigation of the relevant ecological literature and (...) the development of an explicit theoretical framework in the philosophy of science. It addresses issues in the philosophy of ecology that are of particular importance for the deployment of ecology in the solution of environmental problems. It will have a cross-disciplinary appeal and will interest students and professionals in science, the philosophy of science, and environmental studies as well as policy-makers. (shrink)

The balance of nature concept is an old idea that manifests itself in anumber of forms in population and community ecology. This paper focuseson population ecology, where controversy surrounding the balance ofnature takes the form of perennial debates over the significance ofdensity dependence, population regulation, and species interactions suchas competition. One of the most striking features of these debates, overthe course of the previous century in ecology, is the tendency to arguethe case on largely conceptual grounds. This paper explores twoquestions. (...) Why this tendency to settle on conceptual grounds what is soobviously an empirical issue? Are there any good conceptual arguments tobe had in this area? (shrink)

There is a long history of controversy in ecology over the role of competition in determining patterns of distribution and abundance, and over the significance of the mathematical modeling of competitive interactions. This paper examines the controversy. Three kinds of considerations have been involved at one time or another during the history of this debate. There has been dispute about the kinds of regularities ecologists can expect to find, about the significance of evolutionary considerations for ecological inquiry, and about the (...) empirical credentials of theoretical studies of competition. Each of these elements is examined with an eye toward gaining philosophical clarification of the issues involved. In the process, certain shortcomings of contemporary philosophical theories are revealed. In particular, I argue that plausibility arguments based on background considerations are an important part of the model building tradition, but that current accounts of the structure and evaluation of scientific theories do little to illuminate this side of theoretical ecology. (shrink)

Recent controversy over the existence of biological laws raises questions about the cognitive aims of theoretical modeling in that science. If there are no laws for successful theoretical models to approximate, then what is it that successful theories do? One response is to regard theoretical models as tools. But this instrumental reading cannot accommodate the explanatory role that theories are supposed to play. Yet accommodating the explanatory function, as articulated by Brandon and Sober for example, seems to involve us once (...) again in a reliance on laws. The paper concludes that we must rethink both the nature of laws and theoretical explanation in biology. (shrink)

What is the role (or roles) of mathematical theory in ecology and evolutionary biology? How does the construction of such theory advance our understanding? The lack of clear answers to this pair of questions has been a source of controversy both within the sciences themselves, and in the philosophical discussions of these sciences as well. In an attempt to shed some light on these issues, I look at what some biologists have had to say on the matter and at some (...) particular examples. I then draw some morals about the constraints on a successful philosophical treatment of the problem and on the limitations of current philosophical approaches to this type of theoretical explanation. (shrink)

The concept of population is central to ecology, yet it has received little attention from philosophers of ecology. Furthermore, the work that has been done often recycles ideas that have been developed for evolutionary biology. We argue that ecological populations and evolutionary populations, though intimately related, are distinct, and that the distinction matters to practicing ecologists. We offer a definition of ecological population in terms of demographic independence, where changes in abundance are a function of birth and death processes alone. (...) However, demographic independence is insufficient on its own so we supplement it with the idea of shared habitat. An ecological population is a group of organisms of the same species in a habitat that manifests DI. Given the importance of metapopulation dynamics to modern ecology, an account of ecological population must apply to this domain as well. Thus, we extend our definition of ecological population to the metapopulation. To facilitate the extension, we introduce the metahabitat—a collection of spatially segregated habitat patches shared by a single DI population. This enables us to diagnose some unhelpful trends in the metapopulation literature and emphasize the importance of habitat dynamics in pursuit of the goals of theoretical ecology and conservation biology. (shrink)

This paper describes the application of eight statistical and machine-learning methods to derive computer models for predicting mortality of hospital patients with pneumonia from their findings at initial presentation. The eight models were each constructed based on 9847 patient cases and they were each evaluated on 4352 additional cases. The primary evaluation metric was the error in predicted survival as a function of the fraction of patients predicted to survive. This metric is useful in assessing a model’s potential to assist (...) a clinician in deciding whether to treat a given patient in the hospital or at home. We examined the error rates of the models when predicting that a given fraction of patients will survive. We examined survival fractions between 0.1 and 0.6. Over this range, each model’s predictive error rate was within 1% of the error rate of every other model. When predicting that approximately 30°K of the patients will survive, all the models have an error rate of less than 1.5%. The models are distinguished more by the number of variables and parameters that they contain than by their error rates; these differences suggest which models may be the most amenable to future implementation as paper-based guidelines. (shrink)

Although consensus appears to be on the horizon, the foundations of the theory of natural selection remain a matter of controversy. This paper looks at two recent challenges to the emerging "received view" of this theory. It argues that different views of the nature of scientific explanation are playing a pivotal role in the debates. Do explanations in biology fit the covering-law paradigm? What are the explanatory laws of biology like? Until agreement is reached on these fundamental questions, there is (...) little prospect for consensus on the foundations of the theory of natural selection. Furthermore, the three alternative positions identified in this paper each face serious challenges. (shrink)

Sustained controversy over a philosophical issue is often times symptomatic of differing commitments at a more fundamental philosophical level. I will argue that two current debates over the foundations of the theory of natural selection are cases in point. Alexander Rosenberg, at times together with Mary Williams, challenges what is becoming received orthodoxy about the foundations of this theory. He argues that the currently popular propensity interpretation of fitness does not legitimize explanations in terms of natural selection, and that furthermore, (...) the biological fields which typically study the ways in which selection pressures originate in the organism/environment complex are not in fact part of the theory of natural selection at all. His foils in the first case are Robert Brandon, John Beatty and Susan Mills;2 on the second issue he is engaged in debate with Elliott Sober.3 We will see that, although the controversies are ostensibly about the interpretation of fitness, the issues, at bottom, involve the nature of scientific explanation. (shrink)

There is, at present, controversy surrounding the role of the mathematical models which typify the more theoretical portions of ecology and evolutionary biology. Within these sciences there has been controversy about the “testability” of these models, both in terms of the ability of the model to make precise enough claims about the world, and in terms of our ability to determine the values of theoretical parameters. There has been concern, particularly in ecology, about the lack of realism characteristic of most (...) models as well. These are, for the most part, issues involving the nature of theoretical explanation. Much of the current debate about null hypothesis testing, the unfalsifiability of theory, and the role of theory is symptomatic, it would seem, of the fact that these sciences have not settled on what to expect from their most mathematical theories. If there is one emerging theme, it is the need, again especially in ecology, for pluralistic theoretical treatments - which suggests that they may have been expecting too much. (shrink)

We report the identification of a recurrent, 520-kb 16p12.1 microdeletion associated with childhood developmental delay. The microdeletion was detected in 20 of 11,873 cases compared with 2 of 8,540 controls and replicated in a second series of 22 of 9,254 cases compared with 6 of 6,299 controls. Most deletions were inherited, with carrier parents likely to manifest neuropsychiatric phenotypes compared to non-carrier parents. Probands were more likely to carry an additional large copy-number variant when compared to matched controls. The clinical (...) features of individuals with two mutations were distinct from and/or more severe than those of individuals carrying only the co-occurring mutation. Our data support a two-hit model in which the 16p12.1 microdeletion both predisposes to neuropsychiatric phenotypes as a single event and exacerbates neurodevelopmental phenotypes in association with other large deletions or duplications. Analysis of other microdeletions with variable expressivity indicates that this two-hit model might be more generally applicable to neuropsychiatric disease. © 2010 Nature America, Inc. All rights reserved. (shrink)

There has been a significant amount of uncertainty and controversy over the prospects for general knowledge in ecology. Environmental decision makers have begun to despair of ecology's capacity to provide anything more than case by case guidance for the shaping of environmental policy. Ecologists themselves have become suspicious of the pursuit of the kind of genuine nomothetic knowledge that appears to be the hallmark of other scientific domains. Finally, philosophers of biology have contributed to this retreat from generality by suggesting (...) that there really are no laws in biology. This paper addresses these issues by providing a framework for thinking about general knowledge claims in ecology. It introduces a philosophical taxonomy that classifies generalizations into three broad categories – phenomenological, causal and theoretical. It then turns to the difficult problem of laws, arguing that, while there are probably no laws as that term has been understood in philosophy of science, it doesn't follow that everything in ecology is equally contingent. A mechanism for recognizing degrees of contingency in ecological generalizations is developed. The paper concludes by examining the implications of the analysis for the controversies noted at the outset. (shrink)