Thomas A. C. Reydon

Species in biology are traditionally perceived as kinds of organisms about which explanatory and predictive generalizations can be made, and biologists commonly use species in this manner. This perception of species is, however, in stark contrast with the currently accepted view that species are not kinds or classes at all, but individuals. In this paper I investigate the conditions under which the two views of species might be held simultaneously. Specifically, I ask whether upon acceptance of an ontology of species as diachronic segments of the tree of life species can perform the epistemic role of kinds of organisms to which explanatory and predictive generalizations apply. I show that, for species-level segments of the tree of life, several requirements have to be met before the performance of this epistemic role is possible, and I argue that these requirements can be met by defining species according to the Composite Species Concept proposed by Kornet and McAllister in the 1990s

Recently, Barbara Renzi argued that Kuhn's account of scientific change is undermined by mismatches in the analogy that Kuhn supposedly draws between scientific change and biological evolution. We argue that Renzi's criticism is inadequate to Kuhn's account of scientific change, as Kuhn does not draw any precise analogy between the mechanisms of scientific change and biological evolution nor aims to argue that the mechanisms of scientific change and biological evolution are similar in any important respects. Therefore, pointing to mismatches between the central concepts that feature in the descriptions of the two phenomena simply misses the point of Kuhn's analogy. *Received January 2010; revised January 2010. †To contact the authors, please write to: Thomas A. C. Reydon, Leibniz Universität Hannover, Im Moore 21, D‐30167 Hannover, Germany; e‐mail: [email protected]‐hannover.de.

Richard Boyd’s Homeostatic Property Cluster Theory is becoming the received view of natural kinds in the philosophy of science. However, a problem with HPC Theory is that it neglects many kinds highlighted by scientific classifications while at the same time endorsing kinds rejected by science. In other words, there is a mismatch between HPC kinds and the kinds of science. An adequate account of natural kinds should accurately track the classifications of successful science. We offer an alternative account of natural kinds that better recognizes the diversity of epistemic aims scientists have for constructing classifications. That account introduces the idea of a classificatory program and provides criteria for judging whether a classificatory program identifies natural kinds.

A number of debates in philosophy of biology and psychology, as well as in their respective sciences, hinge on particular views about the relationship between genotypes and phenotypes. One such view is that the genotype-phenotype relationship is relatively straightforward, in the sense that a genome contains the ?genes for? the various traits that an organism exhibits. This leads to the assumption that if a particular set of traits is posited to be present in an organism, there must be a corresponding number of genes in that organism's genome to account for those traits. This assumption underlies what can be called the ?counting argument,? in which empirical estimates of the number of genes in a genome are used to support or refute particular hypotheses in philosophical debates about biology and psychology. In this paper, we assess the counting argument as it is used in discussions of the alleged massive modularity of the brain, and conclude that this argument cannot be upheld in light of recent philosophical work on gene concepts and empirical work on genome complexity. In doing so, we illustrate that there are those on both sides of the debate about massive modularity who rely on an incorrect view of gene concepts and the nature of the genotype-phenotype relationship

Present-day thought on the notion of species is troubled by a mistaken understanding of the nature of the issue: while the species problem is commonly understood as concerning the epistemology and ontology of one single scientific concept, I argue that in fact there are multiple distinct concepts at stake. An approach to the species problem is presented that interprets the term ‘species’ as the placeholder for four distinct scientific concepts, each having its own role in biological theory, and an explanation is given of the concepts involved. To illustrate how these concepts are commonly conflated, two widely accepted ideas on species are criticized: species individualism and species pluralism. I argue that by failing to distinguish between the four concepts and their particular roles in contemporary biological theory, these ideas stand in the way of a final resolution of the species problem

While evolutionary thinking is increasingly becoming popular in fields of investigation outside the biological sciences, it remains unclear how helpful it is there and whether it actually yields good explanations of the phenomena under study. Here we examine the ontology of a recent approach to applying evolutionary thinking outside biology, the generalized Darwinism approach proposed by Geoffrey Hodgson and Thorbjørn Knudsen. We examine the ontology of populations in biology and in GD, and argue that biological evolutionary theory sets ontological criteria that GD fails to meet. We suggest two options to revise the population concept in GD: reformulating the concept in terms of inheritance and reproduction such that it comes to pick out individuals similar to evolving populations, or trying to build an adequate population concept on a principle of differential retention instead of differential reproduction. 1 Introduction2 Generalized Darwinism2.1 What is generalized Darwinism?2.2 Darwinian principles3 The Ontology of Generalized Darwinism: What Are Populations?3.1 The population concept of generalized Darwinism3.2 The population concept in evolutionary theory4 Locating Evolving Systems in Generalized Darwinism5 Conclusion

Organizational ecology is commonly seen as a Darwinian research program that seeks to explain the diversity of organizational structures, properties and behaviors as the product of selection in past social environments in a similar manner as evolutionary biology seeks to explain the forms, properties and behaviors of organisms as consequences of selection in past natural environments. We argue that this explanatory strategy does not succeed because organizational ecology theory lacks an evolutionary mechanism that could be identified as the principal cause of organizational diversity. The “evolution” of organizational populations by means of selection, which organizational ecologists put forward as the mechanism responsible for the extant diversity of organizational forms, is not evolution in any proper sense, because organizational populations do not have what it takes to participate in evolutionary processes. This implies that organizational ecology is not a Darwinian research program and that it cannot explain organizational diversity

Natural kinds have been a constant topic in philosophy throughout its history, but many issues pertaining to natural kinds still remain unresolved. This paper considers one of these issues: the epistemic role of natural kinds in scientific investigation. I begin by clarifying what is at stake for an individual scientific field when asking whether or not the field studies a natural kind. I use an example from life science, concerning how biologists explain the similar body shapes of fish and cetaceans, to show that natural kinds play a central epistemic role in scientific explanations that cannot be delegated to other explanatory factors. A task for philosophy, then, is to come up with a theory of natural kinds that adequately accounts for the epistemic role of natural kinds in science. After having sketched the spectrum of available philosophical theories of natural kinds, I argue that none of the available theories adequately performs this task and that therefore the search is still open for a theory that does.

There is an interesting parallel between two debates in different domains of contemporary analytic philosophy. One is the endurantism– perdurantism, or three-dimensionalism vs. four-dimensionalism, debate in analytic metaphysics. The other is the debate on the species problem in philosophy of biology. In this paper I attempt to cross-fertilize these debates with the aim of exploiting some of the potential that the two debates have to advance each other. I address two issues. First, I explore what the case of species implies regarding the feasibility of particular positions in the endurantism– perdurantism debate. I argue that the case of species casts doubt on the recent claim that three-dimensionalism and four-dimensionalism are equivalent descriptions of the same underlying reality. Second, and conversely, I examine whether the metaphysical worry about three-dimensionalism and four-dimensionalism can help us to better understand the nature of biological species. I show that analyzing the thesis that species are individuals against the background of the endurantism– perdurantism debate allows us to explicate two different ways in which this thesis can be interpreted

This paper compares two approaches that attempt to explain the origin of life, or biogenesis. The more established approach is one based on chemical principles, whereas a new, yet not widely known approach begins from a physical perspective. According to the first approach, life would have begun with—often organic—compounds. After having developed to a certain level of complexity and mutual dependence within a non-compartmentalised organic soup, they would have assembled into a functioning cell. In contrast, the second, physical type of approach has life developing within tiny compartments from the beginning. It emphasises the importance of redox reactions between inorganic elements and compounds found on two sides of a compartmental boundary. Without this boundary, “life” would not have begun, nor have been maintained; this boundary—and the complex cell membrane that evolved from it—forms the essence of life.

A major issue in philosophical debates on the species problem concerns the opposition between two seemingly incompatible views of the metaphysics of species: the view that species are individuals and the view that species are natural kinds. In two recent papers in this journal, Olivier Rieppel suggested that this opposition is much less deep than it seems at first sight. Rieppel used a recently developed philosophical account of natural kindhood, namely Richard Boyd’s “homeostatic property cluster” theory, to argue that every species taxon can be conceived of as an individual that constitutes the single member of its own specific natural kind. In this paper I criticize Rieppel’s approach and argue that it does not deliver what it is supposed to, namely an account of species as kinds about which generalized statements can be made.