The ultimate source of explanation in biology is the principle of natural selection. Natural selection means differential reproduction of genes and gene combinations. It is a mechanistic process which accounts for the existence in living organisms of end-directed structures and processes. It is argued that teleological explanations in biology are not only acceptable but indeed indispensable. There are at least three categories of biological phenomena where teleological explanations are appropriate.

This article presents a challenge that those philosophers who deny the causal interpretation of explanations provided by population genetics might have to address. Indeed, some philosophers, known as statisticalists, claim that the concept of natural selection is statistical in character and cannot be construed in causal terms. On the contrary, other philosophers, known as causalists, argue against the statistical view and support the causal interpretation of natural selection. The problem I am concerned with here arises for the statisticalists because the (...) debate on the nature of natural selection intersects the debate on whether mathematical explanations of empirical facts are genuine scientific explanations. I argue that if the explanations provided by population genetics are regarded by the statisticalists as non-causal explanations of that kind, then statisticalism risks being incompatible with a naturalist stance. The statisticalist faces a dilemma: either she maintains statisticalism but has to renounce naturalism; or she maintains naturalism but has to content herself with an account of the explanations provided by population genetics that she deems unsatisfactory. This challenge is relevant to the statisticalists because many of them see themselves as naturalists. (shrink)

Taxonomists in biology have traditionally been concerned to delimit and classify actual (or previously actual) biological forms orkinds. But not all useful classification schemes are of actualisedforms. This paper focuses on the need to delimit and classifynon‐actual forms when offering contrastive explanations in evolutionary biology. Such a classification scheme sorts actual and nonfactual forms according to their modal status. Such a sorting has been offered by theoretical morphologists, but these efforts havepaid insufficient attention to the metaphysics of (...) modality. Contemporary approaches to the metaphysics and epistemology of modalityare also found wanting. The paper ends by arguing that the needed intellectual resources are to be found in the imaginative use of Aristotle. (shrink)

Taxonomists in biology have traditionally been concerned to delimit and classify actual biological forms or kinds. But not all useful classification schemes are of actualised forms. This paper focuses on the need to delimit and classify non‐actual forms when offering contrastive explanations in evolutionary biology. Such a classification scheme sorts actual and non‐actual forms according to their modal status. Such a sorting has been offered by theoretical morphologists, but these efforts have paid insufficient attention to the metaphysics (...) of modality. Contemporary approaches to the metaphysics and epistemology of modality are also found wanting. The paper ends by arguing that the needed intellectual resources are to be found in the imaginative use of Aristotle. (shrink)

Historical explanations in evolutionary biology are commonly characterized as narrative explanations. Examples include explanations of the evolution of particular traits and explanations of macroevolutionary transitions. In this paper I present two case studies of explanations in accounts of pathogen evolution and host-pathogen coevolution, respectively, and argue that one of them is captured well by established accounts of time-sequenced narrative explanation. The other one differs from narrative explanations in important respects, even though it shares some characteristics with them (...) as it is also a population-level historical explanation. I thus argue that the second case represents a different kind of explanation that I call historical explanation of type phenomena. The main difference between the two kinds of explanation is the conceptualization of the explanandum phenomena as particulars or type phenomena, respectively. Narrative explanations explain particulars but also deal with generalization, regularities and type phenomena. Historical explanations of type phenomena, on the other hand, explain multiply realizable phenomena but also deal with particulars. The two kinds of explanation complement each other because they explain different aspects of evolution. (shrink)

I consider recent uses of the notion of neutrality in evolutionary biology and ecology, questioning their relevance to the kind of explanation recently labeled ‘topological explanation’. Focusing on fitness landscapes and genotype-phenotype maps, I explore the explanatory uses of neutral subspaces, as modeled in two perspectives: hyperdimensional fitness landscapes and RNA sequence-structure maps. I argue that topological properties of such spaces account for features of evolutionary systems: respectively, capacity for adaptive evolution toward global optima and (...) mutational robustness of genotypes. Thus many models appealing to “neutral” manifolds provide topological alternatives to hypothetical mechanisms. (shrink)

Knives, birds' wings, and mountain slopes are used for certain purposes: cutting, flying, and climbing. A bird's wings have in common with knives that they have been 'designed' for the purpose they serve, which purpose accounts for their existence, whereas mountain slopes have come about by geological processes independently of their uses for climbing. A bird's wings differ from a knife in that they have not been designed or produced by any conscious agent; rather, the wings, like the slopes, are (...) outcomes of natural processes without any intentional causation. Evolutionary biologists use teleological language and teleological explanations. I propose that this use is appropriate, because teleological explanations are hypotheses that can be subject to empirical testing. The distinctiveness of teleological hypotheses is that they account for the existence of a feature in terms of the function it serves; for example, wings have evolved and persist because flying is beneficial to birds by increasing their chances of surviving and reproducing. Features of organisms that are explained with teleological hypotheses include structures, such as wings; processes, such as development from egg to adult; and behaviours, such as nest building. A proximate explanation of these features is the function they serve; an ultimate explanation that they all share is their contribution to the reproductive fitness of the organisms. I distinguish several kinds of teleological explanations, such as natural and artificial, as well as bounded and unbounded, some of which but not others apply to biological explanations. (shrink)

: Models that fail to satisfy the Markov condition are unstable in the sense that changes in state variable values may cause changes in the values of background variables, and these changes in background lead to predictive error. This sort of error arises exactly from the failure of non-Markovian models to track the set of causal relations upon which the values of response variables depend. The result has implications for discussions of the level of selection: under certain plausible conditions the (...) models of selection presented in such debates will not satisfy the Markov condition when fit to data from real populations. Since this is true both for group and individual level models, models of neither sort correctly represent the causal structure generating, nor correctly explain, the phenomena of interest. (shrink)

Recently, Estes and Arnold claimed to have “solved” the paradox of evolutionary stasis; they claim that stabilizing selection, and only stabilizing selection, can explain the patterns of evolutionary divergence observed over “all timescales.” While Estes and Arnold clearly think that they have identified the processes that produce evolutionary stasis, they have not. Instead, Estes and Arnold identify a particular evolutionary pattern but not the processes that produce that pattern. This mistake is important; the slippage between pattern (...) and process is common in population and quantitative genetics and contributes to a persistent misunderstanding of the nature of explanations in evolutionary biology. †To contact the author, please write to: Philosophy Department, 208 Hovland Hall, Oregon State University, Corvallis, OR 97331‐3902; e‐mail: [email protected]. (shrink)

Evolutionary biology is striking for its ability to explain a large and diverse range of empirical phenomena on the basis of a few general theoretical principles. This article offers a philosophical perspective on the way that evolutionary biology has come to achieve such impressive generality, by focusing on “the strategy of endogenization”. This strategy involves devising evolutionary explanations for biological features that were originally part of the background conditions, or scaffolding, against which such explanations take (...) place. Where successful, the strategy moves biology a step closer to the ideal of explaining as much as possible from evolutionary first principles. The strategy of endogenization is illustrated through a series of biological examples, historical and recent, and its philosophical implications are explored. (shrink)

The ontological dependence of one domain on another is compatible with the explanatory autonomy of the less basic domain. That autonomy results from the fact that the relationship between two domains can be very complex. In this paper I distinguish two different types of complexity, two ways the relationship between domains can fail to be transparent, both of which are relevant to evolutionary biology. Sometimes high level explanations preserve a certain type of causal or counterfactual information which would (...) be lost at the lower level; I argue that this is central to the proper understanding of the adaptationist program. Sometimes high level kinds are multiply realised by lower level kinds: I argue that this is central to the understanding of macroevolution. (shrink)

Evolutionary biology distinguishes differences in survival and reproduction rates due to selection from those due to drift. The distinction is usually thought to be founded in probabilistic facts: a difference in (say) two variants' average lifespans over some period of time that is due to selection is explained by differences in the probabilities relevant to survival; in the purest cases of drift, by contrast, the survival probabilities are equal and the difference in lifespans is a matter of chance. (...) When there is a difference in actual average lifespans there is always a difference in causal histories, but in drift, the causal differences make no contribution to the relevant probabilities. Some writers have claimed that the framework that determines which causes contribute to the probabilities, and so the framework that determines when the relevant probabilities differ and when they are equal, is imposed by modelers rather than being an objective fact of nature, and so that the distinction between selection and drift, however practically useful, is unreal. This paper uses my work on biological probabilities (Bigger than Chaos) and probabilistic explanation (Depth) to argue for the objectivity of, and the importance of the objectivity of, the distinction between selection and drift. (shrink)

Evolutionary ethics has recently become popular again. Some of its representatives elaborate new attempts to derive ethics from evolutionary biology. The attempts, like previous ones, fail because they commit the naturalistic fallacy. Premises from evolutionary biology together with normative premises also do not justify ethical principles. Other representatives argue that evolutionary considerations imply that ethics cannot be justified at all. Their arguments presuppose an unacceptable form of foundationalism. In principle, evolutionary biology might (...) explain some aspects of morality, but in practice explanations are hard to come by. All this does not imply that evolutionary theory is irrelevant in normative settings. To the contrary, it may help us devise guidelines in environmental policy and health care policy. It is to be hoped that evolutionary ethicists will divert their research efforts to the elaboration of such guidelines. (shrink)

Evolutionary epistemologists aim to explain the evolution of cognitive capacities underlying human knowledge and also the processes that generate knowledge, for example in science. There can be no doubt that our cognitive capacities are due in part to our evolutionary heritage. But this is an uninformative thesis. All features of organism have indeed been shaped by evolution. A substantive evolutionary explanation of cognition would have to provide details about the evolutionary processes involved. Evolutionary epistemology (...) has not provided any details. Considering progress of theorizing in science, evolutionary epistemologists have proposed many different analogies between natural selection and selection in science. As yet, the analogies have not been fruitful. The entire program of evolutionary epistemology is programmatic. Evolutionary epistemologists have also moved beyond explanation to justification, the primary issue in traditional epistemology. It turns out that their program presupposes that we can justify knowledge claims in traditional ways. Evolutionary biology is not a proper tool for the justification of beliefs. (shrink)

Kenneth Schaffner has argued that evolutionary theory, strictly understood, cannot support the functional ascriptions used in adaptational functional explanations. Although the causal ascription clause in these ascriptions is supported, the goal-ascription clause cannot be, since it imports anthropocentric features deriving from a vulgar understanding of evolutionary theory. I argue that an etiological interpretation of selectional explanations sanctions both the causal and goal-ascription clauses of functional ascriptions and provides a way to understand teleological explanation within evolutionary (...) class='Hi'>biology. (shrink)

Biology cannot accommodate all aspects of culture. Aspects of culture that a biological approach can take into account can be covered by the biological categories of phenotype and environment. There is no need to treat culture as a separate category. Attempts to elaborate biological explanations of cultural variation will meet with success only if biologists expand theories of development, and integrate them in evolutionary biology. The alternative — elaborating the idea of so-called cultural inheritance — makes little (...) sense from a biological point of view. (shrink)

Explanation in biology has long been characterized as being very different from explanation in other scientific disciplines, very much so from explanation in physics. One of the reasons was the existence in biology of explanation types that were unheard of in the physical sciences: teleological explanations (e.g. Hull 1974), evolutionary explanations (e.g. Mayr 1988), or even functional explanations (e.g. Neander 1991). More recently, and owing much to the rise of molecular biology, biological (...) explanations have been depicted as mechanisms (e.g; Machamer, Darden and Craver 2000). The aim of this volume is to shed some new light on the diversity of explanation types in biology. What are the different types of explanation that occur in biology? Are these types of explanation specific to particular sub-disciplines of biology, or to particular types of problems across biology? How do they relate to each another? Do they compete with one another for answering the same questions? Or do they complement each other, providing insights to different questions? What are the reasons for such diversity? Can this diversity be overcome by a broader unifying model of explanation or is it more profound and irreducible? Why? This volume aims at making sense of this diversity of types of explanations that are found in biology, of their relationship with one another. After all, explanation in biology may prove not only different from explanation in the physical sciences, but also much more diverse than originally anticipated. (shrink)

In recent years, the explanatory term “scaffold” has been gaining prominence in evolutionary biology. This notion has a long history in other areas, in particular, developmental psychology. In this paper, we connect these two traditions and identify a specific type of explanatory strategy shared between them, namely scaffolding explanations. We offer a new definition of “scaffold” anchored in the explanatory practices of evolutionary biologists and developmental psychologists that has yet to be clearly articulated. We conclude by offering (...) a systematic overview of the various dimensions of scaffolding explanations that further suggests both their usefulness and range of application. (shrink)

Biology and history are often viewed as closely related disciplines, with biology informed by history, especially in its task of charting our evolutionary past. Maximizing the opportunities for cross-fertilization in these two fields requires an accurate reckoning of their commonalities and differences-precisely what this volume sets out to achieve. Specially commissioned essays by a team of recognized international researchers cover the full panoply of topics in these fields and include notable contributions on the correlativity of evolutionary (...) and historical explanations, applying to history the latest causal-mechanical approach in the philosophy of biology, and the question of generalized laws that might pertain across the two subjects. The collection opens with a vital interrogation of general issues on explanation that apart from potentially fruitful areas of interaction (could the etiology of the causal-mechanical perspective in biology account for the historical trajectory of the Roman Empire?) this volume also seeks to chart relative certainties distinguishing explanations in biology and history. It also assesses techniques such as the use of probabilities in biological reconstruction, deployed to overcome the inevitable gaps in physical evidence on early evolution. Methodologies such as causal graphs and semantic explanation receive in-depth analysis. Contributions from a host of prominent and widely read philosophers ensure that this new volume has the stature of a major addition to the literature. (shrink)

The pervasive use of computer simulations in the sciences brings novel epistemological issues discussed in the philosophy of science literature since about a decade. Evolutionary biology strongly relies on such simulations, and in relation to it there exists a research program (Artificial Life) that mainly studies simulations themselves. This paper addresses the specificity of computer simulations in evolutionary biology, in the context (described in Sect. 1) of a set of questions about their scope as explanations, the (...) nature of validation processes and the relation between simulations and true experiments or mathematical models. After making distinctions, especially between a weak use where simulations test hypotheses about the world, and a strong use where they allow one to explore sets of evolutionary dynamics not necessarily extant in our world, I argue in Sect. 2 that (weak) simulations are likely to represent in virtue of the fact that they instantiate specific features of causal processes that may be isomorphic to features of some causal processes in the world, though the latter are always intertwined with a myriad of different processes and hence unlikely to be directly manipulated and studied. I therefore argue that these simulations are merely able to provide candidate explanations for real patterns. Section 3 ends up by placing strong and weak simulations in Levins’ triangle, that conceives of simulations as devices trying to fulfil one or two among three incompatible epistemic values (precision, realism, genericity). (shrink)

Darwinian evolutionary biology has often been criticized for appealing to the notion of 'chance' in its explanations. According to some critics, such appeals exhibit the explanatory poverty of evolutionary theory. In response, defenders of Darwinism sometimes downplay the importance of 'chance' in evolution. I believe that both of these approaches are mistaken. The main thesis of this paper is that the term 'chance' encompasses a number of distinct concepts, and that at least some of these concepts serve (...) essential explanatory functions in evolutionary biology. This claim is defended by way of an historical survey of the major concepts of 'chance' in the history of evolutionary biology, especially the concepts used by Jean Baptiste Lamarck, Charles Darwin, and Sewall Wright. An examination of their biologies shows how the concepts of 'chance' used cohere with their major scientific objectives and methods. These concepts survive and continue to function as important explanatory factors in contemporary evolutionary biology. Examples of such usage are given, and the explanatory status of 'chance' assessed. (shrink)

Variational evolutionary theory as advocated by Darwin is not a single theory, but a bundle of related but independent theories, namely: (a) variational evolution; (b) gradualism rather than large leaps; (c) processes of phyletic evolution and of speciation; (d) causes for the formation of varying individuals in populations and for the action of selective agents; and (e) all organisms evolved from a common ancestor. The first four are nomological-deductive explanations and the fifth is historical-narrative. Therefore evolutionary theory must (...) be divided into nomological and historical theories which are both testable against objective empirical observations. To be scientific, historical evolutionary theories must be based on well corroborated nomological theories, both evolutionary and functional. Nomological and general historical evolutionary theories are well tested and must be considered as strongly corroborated scientific theories. Opponents of evolutionary theory are concerned only with historical evolutionary theories, having little interest in nomological theory. Yet given a well corroborated nomological evolutionary theory, historical evolutionary theories follow automatically. If understood correctly, both forms of evolutionary theories stand on their own as corroborated scientific theories and should not be labeled as facts. (shrink)

This paper uses the framework of Formal Darwinism (FD) to evaluate organism-centric critiques of the Modern Synthesis (MS). The first section argues that the FD project reconciles two kinds of selective explanations in biology. Thus it is not correct to say that the MS neglects organisms—instead, it explains organisms’ design, as argued in the second section. In the third section I employ a concept of the organism derived from Kant that has two aspects: the parts presupposing the whole, and (...) the productivity of the parts in relation to the whole. The first aspect corresponds to the “design” that FD explains, whereas the second aspect is something about which the MS is largely silent. (shrink)

It is clear from the above discussion that if I had wished to do so I could have truthfully presented every paper as either testing a prediction, presenting evidence needed in the test of a prediction, or presentin a D-N explanation. (I would not have been able to do this if I had not been sufficiently familiar with the evolutionary literature to recognize what hypotheses were at stake in several of the papers; even when the authors mention the (...) hypotheses they frequently do so only in enough detail to put their paper in context for the knowledgeable biologist.) Since these biologists are working in a period of normal science under the paradigm of the modern synthetic theory of evolution, none of these papers is presented as a test of the modern synthetic theory; but since this theory was used in the derivation of each prediction, each one is a test of it as well as of the hypothesis mentioned. Thus, once we learn to recognize the predictions beneath their cloaks of invisibility, we discover that prediction testing is not, as philosophers have claimed, at best peripheral to evolutionary biology; it is central to evolutionary biology. (shrink)

Robustness analysis is widespread in science, but philosophers have struggled to justify its confirmatory power. We provide a positive account of robustness by analysing some explicit and implicit uses of within and across-model robustness in evolutionary theory. We argue that appeals to robustness are usually difficult to justify because they aim to increase the likeliness that a phenomenon obtains. However, we show that robust results are necessary for explanations of phenomena with specific properties. Across-model robustness is necessary for how-possibly (...) explanations of multiply instantiated phenomena, while within-model robustness is necessary for explanations of phenomena with multiple evolutionary starting points. In such cases, the appeal of robustness is explanatory rather than confirmatory. (shrink)

Evolutionary systems biology (ESB) aims to integrate methods from systems biology and evolutionary biology to go beyond the current limitations in both fields. This article clarifies some conceptual difficulties of this integration project, and shows how they can be overcome. The main challenge we consider involves the integration of evolutionary biology with developmental dynamics, illustrated with two examples. First, we examine historical tensions between efforts to define general evolutionary principles and articulation of (...) detailed mechanistic explanations of specific traits. Next, these tensions are further clarified by considering a recent case from another field focused on developmental dynamics: stem cell biology. In the stem cell case, incompatible explanatory aims block integration. Experimental approaches aim at mechanistic explanation while dynamical system models offer explanation in terms of general principles. We then discuss an ESB case in which integration succeeds: search for general attractors using a dynamical systems framework synergizes with the experimental search for detailed mechanisms. Contrasts between the positive and negative cases suggest general lessons for achieving an integrated understanding of developmental and evolutionary dynamics. The key integrative move is to acknowledge two complementary aims, both relevant to explanation: identifying the space of possible dynamic states and trajectories, and mechanistic understanding of causal interactions underlying a specific phenomenon of interest. These two aims can support one another in a joint project characterizing dynamic aspects of evolving lineages. This more inclusive project can lead to insights that cannot be reached by either approach in isolation. (shrink)

The scope of this paper can be clarified by means of a well-known phenomenon that is usually called ‘industrial melanism’: the fact that the melanic form of the peppered moth became dominant in industrial areas in England in the second half of the nineteenth century. Such changes in relative phenotype frequencies are important explananda for population biologists. Apart from trying to explain such changes over time, population biologists also often try to explain differences between populations, e.g. why yellow shell colour (...) is dominant in certain colonies of land snails and almost absent in other colonies. The causal explanations that are given to address such explananda are the objects of analysis in this paper. Our primary aim is to explicate their structure: we want to capture the typical ingredients of causal explanations in population biology, and their organisation. Based on this explication, we discuss how natural selection fits into recent mechanical philosophy of science, and engage in the debate on the nature of evolutionary theory. (shrink)

My contribution to this Symposium focuses on the links between sexuality and reproduction from the evolutionary point of view.' The relation between women's sexuality and reproduction is particularly importantb ecause of a vital intersectionb etweenp olitics and biology feminists have noticed, for more than a century, that women's identity is often defined in terms of her reproductive capacity. More recently, in the second wave of the feminist movement in the United States, debates about women'si dentityh ave explicitlyi ncludeds (...) exuality;m uch feminist argument in the late 1960's and early 1970's involved an attempt to separate out an autonomous female sexuality from women's reproductive functions. It is especially relevant, then, to examine biological arguments, particularlye volutionarya rgumentst, o see what they say about whether and how women's sexuality is related to reproduction. We shall find that many evolutionarya rgumentss eem to supportt he direct linkingo f female sexualitya nd reproductionY. et I will argue that this supporti s not well-groundedI. n fact, I think evolutionarye xplanationso f female sexuality exemplify how social beliefs and social agendas can influence very basic biological explanations of fundamental physiological processes. In this paper, I shall spend some time spelling out a few examples in which assumptions about the close link between reproduction and sexuality yield misleading results, then I shall conclude with a discussion of the consequences of this case study for issues in the philosophy of science. (shrink)

The design argument for the existence of God took a probabilistic turn in the 17 th and 18 th centuries. Earlier versions, such as Thomas Aquinas' 5 th way, usually embraced the premise that goal-directed systems (things that "act for an end" or have a function) must have been created by an intelligent designer. This idea – which we might express by the slogan "no design without a designer" – survived into the 17 th and 18 th centuries, 1 and (...) it is with us still in the writings of many creationists. The new version of the argument, inspired by the emerging mathematical theory of probability, removed the premise of necessity. It begins with the thought that goal-directed systems might have arisen by intelligent design or by chance; the problem is to discern which hypothesis is more plausible. With the epistemic concept of plausibility characterized in terms of the mathematical concept of probability, the design argument was given a new direction. The new probabilistic perspective did not extinguish the older idea of "no design without a designer." The two conflicting approaches coexisted, often with less than perfect clarity about their fundamental difference. At the same time, the details of how the probabilistic perspective ought to be articulated were slow in emerging. These characteristics of uneven development are exemplified in a debate that took place in the 18 th century among three probabilists – John Arbuthnot, Nicholas Bernoulli, and Abraham DeMoivre – on the proper explanation of human sex ratio. Arbuthnot proposed a probabilistic version of the design argument, claiming that it is intelligent design, not chance, that provides the better explanation of why slightly more boys than girls are born each year. Bernoulli rejected Arbuthnot's argument. DeMoivre defended Arbuthnot against Bernoulli's criticisms. The problem of explaining sex ratio, both in human populations and in the rest of nature, experienced another transformation after 1859 --it became a problem for the theory of evolution by natural selection. Darwin (1871) addressed the question in the first edition of The Descent of Man but withdrew his suggestion in the second (Darwin 1874). Carl Düsing (1884) provided a mathematical model that moved beyond the explanation Darwin offered. Fisher (1930) added the new idea of parental expenditure. Williams (1966) argued that the sex ratios found in nature provide the opportunity to test hypotheses of group selection against hypotheses of individual selection. Hamilton (1967) constructed a model that generalizes Fisher's approach and represents the effects of both group and individual selection. The theory of natural selection gradually developed the ability to predict sex ratios, not just explain them post hoc. (shrink)

Adaptationist accounts of morality attempt to explain the evolution of morality in terms of the selective advantage that judging in moral terms secured for our ancestors (e.g. Ruse 1998; Joyce 2006; Street 2006). So-called by-product explanations of morality have been presented as an alternative to adaptationist accounts (e.g. Prinz 2009; Ayala 2010; cf. Darwin 2004/1871). In assessing the relationship between adaptationist and by-product accounts, care must be taken to distinguish several related but importantly different notions: innateness, adaptation, exaptation, spandrel, and (...) by-product. (shrink)

In recent years, an increasing number of medical books and papers attempting to analyse the concepts of health and disease from the perspective of evolutionary biology have been published.This paper introduces the evolutionary approach to health and disease in an attempt to illuminate the premisses and the framework of Darwinian medicine. My primary aim is to analyse to what extent evolutionary theory provides for a biological definition of the concept of disease. This analysis reveals some important (...) differences between functional explanations in the field of evolutionary biology and functional explanations in the field of medicine. Moreover, I shall argue that the biological functions relevant to the health of an organism cannot be determined on the basis of evolutionary theory. Accordingly, it seems that Darwinian medicine does not provide for the definition of a biological concept of disease. Still,Darwinian medicine may suggest why we are susceptible to certain diseases; it might also prove a suggestive heuristic on the basis of which new hypotheses concerning relevant treatments of various diseases might be advanced. (shrink)

The notion of how-possibly explanations emerged with William Dray in response to Carl Hempel’s influential deductive-nomological model of scientific explanation. Dray’s aim was to distinguish explanations of states of affairs that might occur, in contrast to the aim of D-N explanations working to establish that states of affairs must actually occur. More recently, interest in how-possibly explanations has been particularly keen among philosophers of biology. One of the concerns philosophers of biology have focused on is whether how-possibly (...) explanations are “complete” explanations. Dray considered how-possibly explanations to be complete explanations, but the view that they are incomplete explanations became prominent with Robert Brandon’s articulation of successful adaptation explanation in evolutionary biology. According to Brandon, how-possibly adaptation explanations are incomplete, since they lack the requisite empirical evidence. Moreover, Brandon’s characterization of how-possibly explanation can be seen as having set the stage for thinking broadly about how-possibly explanations in biology. Echoing Brandon’s account for adaptation explanations, for example, David Resnik contends that how-possibly explanations are inherently incomplete, and yet they serve an important heuristic role throughout biology by setting out an agenda for future research. (shrink)

Evolutionary psychology is put forward by its defenders as an extension of evolutionary biology, bringing psychology within the integrated causal chain of the hard sciences. It is extolled as a new paradigm for integrating psychology with the rest of science. We argue that such claims misrepresent the methods and explanations of evolutionary biology, and present a distorted view of the consequences that might be drawn from evolutionary biology for views of human nature. General (...) theses about adaptation in biology are empty schemata, not laws of nature allowing the subsumption of mind under biology. Functional thinking is an indispensable tool for psychology, mostly of value in abstractive unification and as a heuristic, but it gains little from association with evolutionary notions of selection. Thus, we argue, the cherished integrative causal model evaporates, and evolutionary phraseology serves no more than rhetorical purposes. Moreover, the universality of human nature and the evolutionary irrelevance of individual variation are presented as biological truths that psychologists should respect in their approach to mind. On closer inspection, this turns out to be rather dubious biology. Psychology might conceivably be better off as a continuation of biology by different means, but evolutionary psychology does not provide the conceptual integration leading to such a happy union. (shrink)

Until recently, the notions of function and multiple realization were supposed to save the autonomy of psychological explanations. Furthermore, the concept of supervenience presumably allows both dependence of mind on brain and non-reducibility of mind to brain, reconciling materialism with an independent explanatory role for mental and functional concepts and explanations. Eliminativism is often seen as the main or only alternative to such autonomy. It gladly accepts abandoning or thoroughly reconstructing the psychological level, and considers reduction if successful as equivalent (...) with elimination. In comparison with the philosophy of mind, the philosophy of biology has developed more subtle and complex ideas about functions, laws, and reductive explanation than the stark dichotomy of autonomy or elimination. It has been argued that biology is a patchwork of local laws, each with different explanatory interests and more or less limited scope. This points to a pluralistic, domain-specific and multi-level view of explanations in biology. Explanatory pluralism has been proposed as an alternative to eliminativism on the one hand and methodological dualism on the other hand. It holds that theories at different levels of description, like psychology and neuroscience, can co-evolve, and mutually influence each other, without the higher-level theory being replaced by, or reduced to, the lower-level one. Such ideas seem to tally with the pluralistic character of biological explanation. In biological psychology, explanatory pluralism would lead us to expect many local and non-reductive interactions between biological, neurophysiological, psychological and evolutionary explanations of mind and behavior. This idea is illustrated by an example from behavioral genetics, where genetics, physiology and psychology constitute distinct but interrelated levels of explanation. Accounting for such a complex patchwork of related explanations seems to require a more sophisticated and precise way of looking at levels than the existing ideas on (reductive and non-reductive) explanation in the philosophy of mind. (shrink)

Evolutionary biology – or, more precisely, two (purported) applications of Darwin's theory of evolution by natural selection, namely, evolutionary psychology and what has been called human behavioral biology – is on the cusp of becoming the new rage among legal scholars looking for interdisciplinary insights into the law. We argue that as the actual science stands today, evolutionary biology offers nothing to help with questions about legal regulation of behavior. Only systematic misrepresentations or lack (...) of understanding of the relevant biology, together with far-reaching analytical and philosophical confusions, have led anyone to think otherwise. Evolutionary accounts are etiological accounts of how a trait evolved. We argue that an account of causal etiology could be relevant to law if (1) the account of causal etiology is scientifically well-confirmed, and (2) there is an explanation of how the well-confirmed etiology bears on questions of development (what we call the Environmental Gap Objection). We then show that the accounts of causal etiology that might be relevant are not remotely well-confirmed by scientific standards. We argue, in particular, that (a) evolutionary psychology is not entitled to assume selectionist accounts of human behaviors, (b) the assumptions necessary for the selectionist accounts to be true are not warranted by standard criteria for theory choice, and (c) only confusions about levels of explanation of human behavior create the appearance that understanding the biology of behavior is important. We also note that no response to the Environmental Gap Objection has been proffered. In the concluding section of the article, we turn directly to the work of Owen Jones, a leading proponent of the relevance of evolutionary biology to law, and show that he does not come to terms with any of the fundamental problems identified in this article. (shrink)

In this article I consider the challenges for exporting causal knowledge raised by complex biological systems. In particular, James Woodward’s interventionist approach to causality identified three types of stability in causal explanation: invariance, modularity, and insensitivity. I consider an example of robust degeneracy in genetic regulatory networks and knockout experimental practice to pose methodological and conceptual questions for our understanding of causal explanation in biology. †To contact the author, please write to: Department of History and Philosophy of (...) Science, University of Pittsburgh, 1017 Cathedral of Learning, Pittsburgh, PA 15260; e‐mail: [email protected]. (shrink)

In this article, I argue that distinguishing ‘evolutionary’ from ‘Darwinian’ medicine will help us assess the variety of roles that evolutionary explanations can play in a number of medical contexts. Because the boundaries of evolutionary and Darwinian medicine overlap to some extent, however, they are best described as distinct ‘research traditions’ rather than as competing paradigms. But while evolu- tionary medicine does not stand out as a new scientific field of its own, Darwinian medicine is united by (...) a number of distinctive theoretical and methodological claims. For example, evolutionary medicine and Darwinian medicine can be distinguished with respect to the styles of evolutionary explanations they employ. While the former primarily involves ‘forward looking’ explanations, the latter depends mostly on ‘backward looking’ explanations. A forward looking explanation tries to predict the effects of ongoing evolutionary processes on human health and disease in contem- porary environments (e.g., hospitals). In contrast, a backward looking explanation typically applies evolutionary principles from the vantage point of humans’ distant biological past in order to assess present states of health and disease. Both approaches, however, are concerned with the prevention and control of human diseases. In con- clusion, I raise some concerns about the claim that ‘nothing in medicine makes sense except in the light of evolution’. (shrink)

Different types of explanations coexist in present-day biology. Functional explanations describe mechanisms, whereas evolutionary explanations provide answers to the question “why?” mostly by appealing to the past and present action of natural selection. But the relations between these two types of explanations, as well as the relative insights they offer, vary from one domain of research to another. We will illustrate this complex landscape of biological explanations with three examples involving aging, the sex ratio, and the phenomenon of (...) genomic imprinting. We will show that the two types of explanations have recently often progressed towards each other. In consequence, they cease to be “pure” functional or evolutionary explanations and become explanations that may be alternatively considered as functional or evolutionary. (shrink)

Human propensities that are the products of Darwinian evolution may combine to generate a form of social behavior that is not itself a direct result of such pressure. This possibility may provide a satisfying explanation for the origin of socially transmitted rules such as the incest taboo. Similarly, the regulatory processes of development that generated adaptations to the environment in the circumstances in which they evolved can produce surprising and sometimes maladaptive consequences for the individual in modern conditions. These (...) combinatorial aspects of social and developmental dynamics leave a subtle but not wholly uninteresting role for evolutionary biology in explaining the origins of human morality. (shrink)

Chance comes into plays at many levels of the explanation of the evolutionary process; but the unity of sense of this category is problematic. The purpose of this talk is to clarify the meaning of chance at various levels in evolutionary theory: mutations, genetic drift, genetic revolutions, ecosystems, macroevolution. Three main concepts of chance are found at these various levels: luck (popular concept), randomness (probabilistic concept), and contingency relative to a given theoretical system (epistemological concept). After identifying (...) which concept(s) of chance fit(s) with these levels, the question is raised whether these concepts can be reduced to a smaller number, and whether chance in evolutionary theory has a subjective or an objective sense. (shrink)

Evo-devo is a multidisciplinary field that investigates the interplay between evolutionary and developmental processes and brings together different kinds of explanatory strategies. This chapter examines the structure of paradigmatic explanations in evo-devo (e.g., the explanation of the origin of an evolutionary novelty) and raises philosophical questions about explanation in evo-devo. Much research in evo-devo is concerned with studying the developmental mechanisms that constrain and facilitate phenotypic evolution, which suggests that a distinctive feature of evo-devo is that (...) it constructs mechanistic explanations. In this chapter, I discuss three major challenges for thinking about evo-devo as providing mechanistic explanations. First, an explanation of an evolutionary novelty consists of several mechanistic explanations, rather than being a single one. Second, developmental mechanisms are ontogenetically and phylogenetically dynamic and thus difficult to individuate. Third, an explanation of an evolutionary novelty also has a non-mechanistic, historical part. Finally, I discuss whether evo-devo’s emphasis on mechanistic explanation promotes explanatory integration or results in a reductionist view of evolution. (shrink)

Recently, two research traditions that bring together evolutionary biology and medicine, that is to say, Darwinian medicine and evolutionary medicine, have been identified. In this paper, I analyse these two research traditions with respect to explanatory and interdisciplinary integration. My analysis shows that Darwinian medicine does not integrate medicine and evolutionary biology in any strong sense but does incorporate evolutionary concepts into medicine. I also show that backward-looking explanations in Darwinian medicine are not integrated (...) proximate-and-ultimate explanations but functional explanations that include reference to evolutionary concepts. Nevertheless, explanations in Darwinian medicine have heuristic roles as they potentially contribute to conceptual change and tie pieces of knowledge from different fields of medical research together. I argue that Darwinian medicine is an “interfield” that fosters cross-disciplinary exchange between evolutionary biologists and medical researchers and practitioners based on division of labour and separation, rather than unity. Research in evolutionary medicine, on the other hand, happens at the intersection of evolutionary biology and medicine where the two disciplines are already integrated and is designed to produce entangled proximate-evolutionary explanations. My analysis thus adds another important aspect to the philosophical discussion on the distinction between Darwinian medicine and evolutionary medicine. (shrink)

It seems that the above account of explanation-strategy in the area of temperature adaptation underscores many of the points made earlier. First, it discloses the fruitful interaction of classical, evolutionary, and molecular approaches. Secondly, it indicates that biological characterizations are not rival accounts to chemical ones. Thirdly, it stresses the importance of the DNA sequence order in chemical explanations of biological organisms.One feature which this area does not seem to reveal, which genetics does, is the development of a (...) biological (that is, non-chemical) theory which would explain temperature adaptation in nonchemical terms. What this shows is that one should not always expect systematization at the biological level, in the sense of being able to refer many phenomena to a small number of basic principles. The future development of laws and theories in biological terms in this area is, of course, not precluded by the fact that none have yet been discovered. The case does indicate that physical and chemical language and theories are extremely useful in biological investigations, and the physicochemical approach may well be the best approach in this area. In any event, ultimate reduction of the biological to the chemical seems to be a foregone non-controversial conclusion here as elsewhere. (shrink)

The aim of this dissertation is to provide an analysis of central concepts in philosophy of science from the perspective of current molecular and developmental research. Each chapter explores the ways in which particular phenomena or discoveries in molecular biology influences our philosophical understanding of the nature of scientific knowledge. The introductory prologue draws some general connections between the various threads, which revolve around two central themes: causation and explanation. Chapter Two identifies a particular type of causal relation (...) which is widespread across the sciences, but cannot be straightforwardly accommodated by extant accounts of causation and causal explanation. Chapter Three explores how the form of redundant causality identified in the previous chapter plays an important role in causal explanation, by making the effect stable and robust. Chapter Four offers a novel perspective on the debate over biological reductionism by distinguishing between different paradigms of molecular explanation. Chapter Five provides a philosophical analysis of the so-called "Developmental Synthesis" of evolutionary and developmental biology, and suggests a general account of scientific unification grounded in the notion of explanatory relevance. Chapter Six offers an account of dispositional properties inspired by mechanisms of gene regulation, according to which dispositions are not properties of entities, but properties that describe the behavior of abstract idealized models. Finally, Chapter Seven scrutinizes the concept of the molecular ecosystem, a metaphor frequently employed by biologists to describe cellular interactions, but seldom articulated in detail. (shrink)

Evolutionary explanations are not only common in the biological sciences, but also widespread outside biology. But an account of how evolutionary explanations perform their explanatory work is still lacking. This paper develops such an account. I argue that available accounts of explanations in evolutionary science miss important parts of the role of history in evolutionary explanations. I argue that the historical part of evolutionary science should be taken as having genuine explanatory force, and that (...) it provides how‐possibly explanations sensu Dray. I propose an account of evolutionary explanations as comparative‐composite explanations consisting of two distinct kinds of explanations, one processual and one historical, that are connected via the explanandum's evolvability to show how the explanandum is the product of its evolutionary past. The account is both a reconstruction of how evolutionary explanations in biology work and a guideline specifying what kind of explanations evolutionary research programs should develop. (shrink)