This anthology collects some of the most important papers on what is believed to be the major force in evolution, natural selection. An issue of great consequence in the philosophy of biology concerns the levels at which, and the units upon which selection acts. In recent years, biologists and philosophers have published a large number of papers bearing on this subject. The papers selected for inclusion in this book are divided into three main sections covering the history of the subject, (...) explaining its conceptual foundations, and focusing on kin and group selection and higher levels of selection.One of the book's interesting features is that it draws together material from the biological and philosophical literatures. The philosophical literature, having thoroughly absorbed the biological material, now offers conceptual tools suitable for the reworking of the biological arguments. Although a full symbiosis has yet to develop, this anthology offers a unique resource for students in both biology and philosophy.Robert N. Brandon is Professor in the Philosophy Department, Duke University. Richard M. Burian is Professor of Philosophy and Department Chairman, Virginia Polytechnic Institute and State University.A Bradford Book. (shrink)
This paper is divided into three sections. In the first section we offer a retooling of some traditional concepts, namely icons and symbols, which allows us to describe an evolutionary continuum of communication systems. The second section consists of an argument from theoretical biology. In it we explore the advantages and disadvantages of phenotypic plasticity. We argue that a range of the conditions that selectively favor phenotypic plasticity also favor a nongenetic transmission system that would allow for the inheritance of (...) acquired characters. The first two sections are independent, the third depends on both of them. In it we offer an argument that human natural languages have just the features required of an ideal transmission mechanism under the conditions described in section 2. (shrink)
The concept of individuality as applied to species, an important advance in the philosophy of evolutionary biology, is nevertheless in need of refinement. Four important subparts of this concept must be recognized: spatial boundaries, temporal boundaries, integration, and cohesion. Not all species necessarily meet all of these. Two very different types of pluralism have been advocated with respect to species, only one of which is satisfactory. An often unrecognized distinction between grouping and ranking components of any species concept is necessary. (...) A phylogenetic species concept is advocated that uses a grouping criterion of monophyly in a cladistic sense, and a ranking criterion based on those causal processes that are most important in producing and maintaining lineages in a particular case. Such causal processes can include actual interbreeding, selective constraints, and developmental canalization. The widespread use of the biological species concept is flawed for two reasons: because of a failure to distinguish grouping from ranking criteria and because of an unwarranted emphasis on the importance of interbreeding as a universal causal factor controlling evolutionary diversification. The potential to interbreed is not in itself a process; it is instead a result of a diversity of processes which result in shared selective environments and common developmental programs. These types of processes act in both sexual and asexual organisms, thus the phylogenetic species concept can reflect an underlying unity that the biological species concept can not. (shrink)
This paper gives an account of evolutionary explanations in biology. Briefly, the explanations I am primarily concerned with are explanations of adaptations. These explanations are contrasted with other nonteleological evolutionary explanations. The distinction is made by distinguishing the different kinds of questions these different explanations serve to answer. The sense in which explanations of adaptations are teleological is spelled out.
Drift is to evolution as inertia is to Newtonian mechanics. Both are the "natural" or default states of the systems to which they apply. Both are governed by zero-force laws. The zero-force law in biology is stated here for the first time.
In this paper I argue that we can best make sense of the practice of experimental evolutionary biology if we see it as investigating contingent, rather than lawlike, regularities. This understanding is contrasted with the experimental practice of certain areas of physics. However, this presents a problem for those who accept the Logical Positivist conception of law and its essential role in scientific explanation. I address this problem by arguing that the contingent regularities of evolutionary biology have a limited range (...) of nomic necessity and a limited range of explanatory power even though they lack the unlimited projectibility that has been seen by some as a hallmark of scientific laws. (shrink)
In this paper we first briefly review Bell's (1964, 1966) Theorem to see how it invalidates any deterministic "hidden variable" account of the apparent indeterminacy of quantum mechanics (QM). Then we show that quantum uncertainty, at the level of DNA mutations, can "percolate" up to have major populational effects. Interesting as this point may be it does not show any autonomous indeterminism of the evolutionary process. In the next two sections we investigate drift and natural selection as the locus of (...) autonomous biological indeterminacy. Here we conclude that the population-level indeterminacy of natural selection and drift are ultimately based on the assumption of a fundamental indeterminacy at the level of the lives and deaths of individual organisms. The following section examines this assumption and defends it from the determinists' attack. Then we show that, even if one rejects the assumption, there is still an important reason why one might think evolutionary theory (ET) is autonomously indeterministic. In the concluding section we contrast the arguments we have mounted against a deterministic hidden variable account of ET with the proof of the impossibility of such an account of QM. (shrink)
Millstein [Bio. Philos. 17 (2002) 33] correctly identies a serious problem with the view that natural selection and random drift are not conceptually distinct. She offers a solution to this problem purely in terms of differences between the processes of selection and drift. I show that this solution does not work, that it leaves the vast majority of real biological cases uncategorized. However, I do think there is a solution to the problem she raises, and I offer it here. My (...) solution depends on solving the biological analogue of the reference class problem in probability theory and on the reality of individual fitnesses. (shrink)
Richard Lewontin's (1970) early work on the units of selection initiated the conceptual and theoretical investigations that have led to the hierarchical perspective on selection that has reached near consensus status today. This paper explores other aspects of his work, work on what he termed continuity and quasi-independence, that connect to contemporary explorations of modularity in development and evolution. I characterize such modules and argue that they are the true units of selection in that they are what evolution by natural (...) selection individuates, selects among, and transforms. (shrink)
In this paper Wimsatt's analysis of units of selection is taken as defining the units of selection question. A definition of levels of selection is offered and it is shown that the levels of selection question is quite different from the units of selection question. Some of the relations between units and levels are briefly explored. It is argued that the levels of selection question is the question relevant to explanatory concerns, and it is suggested that it is the question (...) relevant to ontological concerns. (shrink)
Robert Brandon is one of the most important and influential of contemporary philosophers of biology. This collection of his recent essays covers all the traditional topics in the philosophy of evolutionary biology and as such could serve as an introduction to the field. There are essays on the nature of fitness, teleology, the structure of the theory of natural selection, and the levels of selection. The book also deals with newer topics that are less frequently discussed but are of growing (...) interest, for example the evolution of human language and the role of experimentation in evolutionary biology. A special feature of the collection is that it avoids jargon and is written in a style that will appeal to working evolutionary biologists as well as philosophers. (shrink)
Barrett et al. present four puzzles for the ZFEL-view of evolution that we present in our 2010 book, Biology’s First Law: The Tendency for Diversity and Complexity to Increase in Evolutionary Systems. Our intent in writing this book was to present a radically different way to think about evolution. To the extent that it really is radical, it will be easy to misunderstand. We think Barrett et al. have misunderstood several crucial points and so we welcome the opportunity to clarify.
Darwin's theory of evolution by natural selection provided the first, and only, causal-mechanistic account of the existence of adaptations in nature. As such, it provided the first, and only, scientific alternative to the “argument from design”. That alone would account for its philosophical significance. But the theory also raises other philosophical questions not encountered in the study of the theories of physics. Unfortunately the concept of natural selection is intimately intertwined with the other basic concepts of evolutionary theory—such as the (...) concepts of fitness and adaptation —that are themselves philosophically controversial. Fortunately we can make considerable headway in getting clear on natural selection without solving all of those outstanding problems. (shrink)
Genic selectionists (Williams 1966; Dawkins 1976) defend the view that genes are the (unique) units of selection and that all evolutionary events can be adequately represented at the genic level. Pluralistic genic selectionists (Sterelny and Kitcher 1988; Waters 1991; Dawkins 1982) defend the weaker view that in many cases there are multiple equally adequate accounts of evolutionary events, but that always among the set of equally adequate representations will be one at the genic level. We describe a range of cases (...) all involving stable equilibria actively maintained by selection. In these cases genotypic models correctly show that selection is active at the equilibrium point. In contrast, the genic models have selection disappearing at equilibrium. For deterministic models this difference makes no difference. However, once drift is added in, the two sets of models diverge in their predicted evolutionary trajectories. Thus, contrary to received wisdom on this matter, the two sets of models are not empirically equivalent. Moreover, the genic models get the facts wrong. (shrink)
The principle of natural selection is stated. It connects fitness values (actual reproductive success) with expected fitness values. The term 'adaptedness' is used for expected fitness values. The principle of natural selection explains differential fitness in terms of relative adaptedness. It is argued that this principle is absolutely central to Darwinian evolutionary theory. The empirical content of the principle of natural selection is examined. It is argued that the principle itself has no empirical biological content, but that the presuppositions of (...) its applicability are empirical. They form the empirical biological core of evolutionary theory. (shrink)
There is a worry that the ‘major transitions in evolution’ represent an arbitrary group of events. This worry is warranted, and we show why. We argue that the transition to a new level of hierarchy necessarily involves a nonselectionist chance process. Thus any unified theory of evolutionary transitions must be more like a general theory of fortuitous luck, rather than a rigid formulation of expected events. We provide a systematic account of evolutionary transitions based on a second-order regularity of chance (...) events, as stipulated by the ZFEL (Zero Force Evolutionary Law). And in doing so, we make evolutionary transitions explainable and predictable, and so not entirely contingent after all. (shrink)
Population-level theories of evolution—the stock and trade of population genetics—are statistical theories par excellence. But what accounts for the statistical character of population-level phenomena? One view is that the population-level statistics are a product of, are generated by, probabilities that attach to the individuals in the population. On this conception, population-level phenomena are explained by individual-level probabilities and their population-level combinations. Another view, which arguably goes back to Fisher but has been defended recently, is that the population-level statistics are sui (...) generis, that they somehow emerge from the underlying deterministic behavior of the individuals composing the population. Walsh et al. label this the statistical interpretation. We are not willing to give them that term, since everyone will admit that the population-level theories of evolution are statistical, so we will call this the emergentist statistical interpretation. Our goals are to show that: This interpretation is based on gross factual errors concerning the practice of evolutionary biology, concerning both what is done and what can be done; its adoption would entail giving up on most of the explanatory and predictive projects of evolutionary biology; and finally a rival interpretation, which we will label the propensity statistical interpretation succeeds exactly where the emergentist interpretation fails. (shrink)
In this paper the common association between ontological reductionism and a methodological position called 'Mechanism' is discussed. Three major points are argued for: (1) Mechanism is not to be identified with reductionism in any of its forms; in fact, mechanism leads to a non-reductionist ontology. (2) Biological methodology is thoroughly mechanistic. (3) Mechanism is compatible with at least one form of teleology. Along the way the nature and value of scientific explanations, some recent controversies in biology and why reductionism has (...) proven to be such an attractive position are discussed. (shrink)
Clatterbuck et al. (Biol Philos 28: 577–592, 2013) argue that there is no fact of the matter whether selection dominates drift or vice versa in any particular case of evolution. Their reasons are not empirically based; rather, they are purely conceptual. We show that their conceptual presuppositions are unmotivated, unnecessary and overly complex. We also show that their conclusion runs contrary to current biological practice. The solution is to recognize that evolution involves a probabilistic sampling process, and that drift is (...) a deviation from probabilistic expectation. We conclude that conceptually, there are no problems with distinguishing drift from selection, and empirically—as modern science illustrates—when drift does occur, there is a quantifiable fact of the matter to be discovered. (shrink)
Reciprocal altruism was originally formulated in terms of individual selection and most theorists continue to view it in this way. However, this interpretation of reciprocal altruism has been challenged by Sober and Wilson (1998). They argue that reciprocal altruism (as well as all other forms of altruism) evolves by the process of group selection. In this paper, we argue that the original interpretation of reciprocal altruism is the correct one. We accomplish this by arguing that if fitness attaches to (at (...) minimum) entire life cycles, then the kind of fitness exchanges needed to form the group-level in such situations is not available. Reciprocal altruism is thus a result of individual selection and when it evolves, it does so because it is individually advantageous. (shrink)
Sober (1992) has recently evaluated Brandon's (1982, 1990; see also 1985, 1988) use of Salmon's (1971) concept of screening-off in the philosophy of biology. He critiques three particular issues, each of which will be considered in this discussion.
These days 'evolution' is usually defined as any change in the relative frequencies of genes in a population over time. This definition and some obvious alternatives are examined and rejected. The criticism of these definitions points out the need for a more holistic analysis of genotypes. I attempt such analysis by introducing measures of similarity of whole genotypes and then by grouping genotypes into similarity classes. Three sorts of measures of similarity are examined: a measure of structural similarity, a measure (...) of functional similarity and one of relational or historical similarity. The functional approach is shown to be superior and a definition of 'evolution' is suggested. (shrink)
This paper proposes a revision of our understanding of causation that is designed to address what Hartry Field has suggested is the central problem in the metaphysics of causation today: reconciling Bertrand Russell’s arguments that the concept of causation can play no role in the advanced sciences with Nancy Cartwright’s arguments that causal concepts are essential to a scientific understanding of the world. The paper shows that Russell’s main argument is, ironically, very similar to an argument that Cartwright has put (...) forward against the truth of universal laws of nature. The paper uses this insight to develop an account of causation that does justice to traditional views yet avoids the arguments of Russell. (shrink)
Christopher Hitchcocks discussion of my use of screening-off in analyzing the causal process of natural selection raises some interesting issues to which I am pleased to reply. The bulk of his article is devoted to some fairly general points in the theory of explanation. In particular, he questions whether or not my point that phenotype screens off genotype from reproductive success (in cases of organismic selection) supports my claim that the explanation of differential reproductive success should be in terms of (...) phenotypic differences, not genotypic differences. I will respond to this and show why the two supposed counter-examples to my position fail. (shrink)
Kary (1990) defends the view that evolution by natural selection can be adequately explained in terms of a theory incorporating only a single level of selection. Here I point out some of the inherent inadequacies of such a theory.
Christopher Hitchcock‘s discussion of my use of screening-off in analyzing the causal process of natural selection raises some interesting issues to which I am pleased to reply. The bulk of his article is devoted to some fairly general points in the theory of explanation. In particular, he questions whether or not my point that phenotype screens off genotype from reproductive success supports my claim that the explanation of differential reproductive success should be in terms of phenotypic differences, not genotypic differences. (...) I will respond to this and show why the two supposed counter-examples to my position fail. (shrink)
In this Element, we extend our earlier treatment of biology's first law. The law says that in any evolutionary system in which there is variation and heredity, there is a tendency for diversity and complexity to increase. The law plays the same role in biology that Newton's first law plays in physics, explaining what biological systems are expected to do when no forces act, in other words, what happens when nothing happens. Here we offer a deeper explanation of certain features (...) of the law, develop a quantitative version of it, and explore its consequences for our understanding of diversity and complexity. (shrink)