Some recent cognitive-scientific research suggests that a considerable amount of intelligent action is generated not by the systematic activity of internal representations, but by complex interactions involving neural, bodily, and environmental factors. Following an analysis of this threat to representational explanation, we pursue an analogy between the role of genes in the production of biological form and the role of neural states in the production of behaviour, in order to develop a notion of genic representation. In both cases an (...) appeal to normal ecological context is used to balance multi-factoral, interactive causal determination against the intuition that certain aspects of the causal nexus play a special role in promoting adaptive success. Certain worries abut this vision help us to get a better grip on the concept of genic representation itself. We end with a puzzle concerning the relation between cognition and representation. (shrink)

I clarify the difference between pluralist and monist interpretations of levels of selection disputes. Lloyd has challenged my claim that a plurality of models correctly accounts for situations such as maintenance of the sickle-cell trait, and I revisit this example to show that competing theories don’t disagree about the existence of ‘high-level’ or ‘lowlevel’ causes; rather, they parse these causes differently. Applying Woodward’s theory of causation, I analyze Sober’s distinction between ‘selection of’ versus ‘selection for’. My analysis shows that this (...) distinction separates true causes from pseudocauses, but it also reveals that the distinction is irrelevant to the levels debate; it makes no sense to say true causes are at higher levels and not lower levels. The levels debate is not about separating real causes from pseudocauses; it’s about finding useful ways to parse and disentangle causes. (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)

A recent debate concerning the representational content of DNA in developmental processes has opposed “dynamicists” and “computationalists.” I review the arguments in favor of a representational interpretation of the role of genes, and show that they are inconclusive. There is a very restricted sense in which genes can be said to represent something, and stronger claims about DNA being a program for the construction of an organism are overstatements. I also show that arbitrariness, taken by representationalists to be a central (...) criterion for identifying representational vehicles, is neither a sufficient nor a necessary condition to qualify as a representation. Finally, I propose a relatively new way to define what programs are, which implies that genetic regulatory networks shouldn’t be thought of as being programs. As a consequence, insofar as cognition and development share similar mechanisms, any computational account of cognition should be significantly weakened. (shrink)

Several evolutionary biologists have used a parsimony argument to argue that the single gene is the unit of selection. Since all evolution by natural selection can be represented in terms of selection coefficients attaching to single genes, it is, they say, "more parsimonious" to think that all selection is selection for or against single genes. We examine the limitations of this genic point of view, and then relate our criticisms to a broader view of the role of causal concepts (...) and the dangers of reification in science. (shrink)

Since the fundamental challenge that I laid at the doorstep of the pluralists was to defend, with nonderivative models, a strong notion of genic cause, it is fatal that Waters has failed to meet that challenge. Waters agrees with me that there is only a single cause operating in these models, but he argues for a notion of causal ‘parsing’ to sustain the viability of some form of pluralism. Waters and his colleagues have some very interesting and important ideas (...) about the sciences, involving pluralism and parsing or partitioning causes, but they are ideas in search of an example. He thinks he has found an example in the case of hierarchical and genic selection. I think he has not. (shrink)

Since the fundamental challenge that I laid at the doorstep of the pluralists was to defend, with nonderivative models, a strong notion of genic cause, it is fatal that Waters has failed to meet that challenge. Waters agrees with me that there is only a single cause operating in these models, but he argues for a notion of causal `parsing' to sustain the viability of some form of pluralism. Waters and his colleagues have some very interesting and important ideas (...) about the sciences, involving pluralism and parsing or partitioning causes, but they are ideas in search of an example. He thinks he has found an example in the case of hierarchical and genic selection. I think he has not. (shrink)

Fussend auf der Quantentheorie und Wellenmechanik, sowie unter Berücksichtigung der „Topik” desAristoteles und der SystemeDrieschs undWhiteheads studiert der Autor die Resultate welche die biologische Forschung bis jetzt bezüglich der Erscheinungen der biologischen Induktion, der Stimulation und der Vererbung geliefert hat und umreisst schliesslich eine allgemeine Theorie dieser Erscheinungen, welche sie durch interne, normative Beziehungen zwischen verschiedenen Ganzheiten erklärt. Diese Ganzheiten haben als solche keine Existenz im Raum, sondern nur in der Zeit in derselben Weise wie bei einem grammatikalischen, esthetischen oder (...) ethischen Gesetz. Diese Gesetze äussern sich mittels Symbolen, welche ihren Sinn repräsentieren und die Substanzen, welche Induktion, Stimulation oder Vererbung bewirken, werden als solche Symbole aufgefasst, welche ihre Wirkung nicht produzieren, sondern sie nur in einer andern Ganzheit induzieren, einer Ganzheit, welche auf das betreffende Symbol anspricht und welche dem Gesetz, das durch das Symbol repräsentiert wird, gehorcht.Se basant sur la théorie des quanta et sur la mécanique des ondes, ainsi que sur la „Topique” d'ARistote et les systèmes philosophiques deDriesch et deWhitehead, l'auteur examine les résultats biologiques relatives aux phénomènes de l'induction, de la stimulation et de l'activité des gènes acquis jusqu'à présent et propose en conclusion l'esquisse d'une théorie générale de ces phénomènes qui les explique par des relations internes et normatives ayant lieu entre différentes entités. Ces entités ont une existence non spatiale, mais temporelle, semblablement à des lois grammaticales, esthétiques ou éthiques. Ces lois s'expressent par le moyen de symboles qui représentent leur sens et les substances inducteurs, stimulateurs ou géniques sont interprêtées comme étant des symboles semblables qui ne produisent pas leurs effets mais les induisent seulement dans une autre entité qui répond au symbole et obéit à la loi normative que ce dernier représente. (shrink)

Rosenberg (1983), in his comments on our article (Sober and Lewontin 1982) concerning the units of selection controversy, has matters precisely backwards. We suggest Rosenberg alludes to a quite different view of the units of selection controversy, one that he never shows to have mattered to any biologists engaged in the dispute. We also reject Rosenberg's remark that the hypothesis of genic selection is currently predictively vacuous.

In a recent paper, Brandon and Nijhout argue against genic selectionism—the thesis, roughly, that evolutionary processes are best understood from the gene’s-eye point of view—by presenting a case in which genic models of selection allegedly make predictions that conflict with the (correct) predictions of higher-level genotypic selection models. Their argument, if successful, would refute the widely held belief that genic models and higher-level models are predictively equivalent. Here, I argue that Brandon and Nijhout fail to demonstrate that (...) the models make incompatible predictions. (shrink)

This paper compares two well-known arguments in the units of selection literature, one due to , the other due to . Both arguments concern the legitimacy of averaging fitness values across contexts and making inferences about the level of selection on that basis. The first three sections of the paper shows that the two arguments are incompatible if taken at face value, their apparent similarity notwithstanding. If we accept Sober and Lewontin's criterion for when averaging genic fitnesses across diploid (...) genotypes is illegitmate, we cannot accept Sober and Wilson's criterion for when averaging individual fitnesses across groups is illegitimate, and vice versa. The final section suggests a possible way of reconciling the two arguments, by invoking an ambiguity in the concept of genic selection. (shrink)

This chapter offers a review of standard views about the requirements for natural selection to shape evolution and for the sorts of ‘units’ on which selection might operate. It then summarizes traditional arguments for genic selectionism, i.e., the view that selection operates primarily on genes (e.g., those of G. C. Williams, Richard Dawkins, and David Hull) and traditional counterarguments (e.g., those of William Wimsatt, Richard Lewontin, and Elliott Sober, and a diffuse group based on life history strategies). It then (...) offers a series of responses to the arguments, based on more contemporary considerations from molecular genetics, offered by Carmen Sapienza. A key issue raised by Sapienza concerns the degree to which a small number of genes might be able to control much of the variation relevant to selection operating on such selectively critical organs as hearts. The response to these arguments suggests that selection acts on many levels at once and that sporadic selection, acting with strong effects, can act successively on different key traits (and genes) while maintaining a balance among many potentially conflicting demands faced by organisms within an evolving lineage. (shrink)

My aim in this paper is to quickly sketch a teleological approach to the problem of isolating the impact of genes on phenotypic characters. I begin by arguing that it is a mistake to think that there will be only one analysis of genetic input suitable for all theoretical interests. My principle focus is Richard Dawkins' argument for genic selectionism. I argue that a teleological analysis of genetic input is what Dawkins requires to establish the right kind of mapping (...) of gene onto phenotype. This comes at a certain cost, however. Accepting the analysis will threaten Dawkins' claims about the teleogogical priority of gene over phenotype. (shrink)

The beanbag genetics controversy can be traced from the dispute between Fisher and Wright, through Mayr''s influential promotion of the issue, to the contemporary units of selection debate. It centers on the claim that genic models of natural selection break down in the face of epistatic interactions among genes during phenotypic development. This claim is explored from both a conceptual and a quantitative point of view, and is shown to be defective on both counts.Firstly, an analysis of the controversy''s (...) theoretical origins demonstrates that this claim derives from a misinterpretation of the conceptual foundations of Fisher''s genetical theory of natural selection, and confounds his fundamentally different concepts of the average excess and average effect of a gene. Secondly, an extension of the genic approach is proposed which models the dynamics of selection among epistatically interacting complexes of many genes. Paradoxically, this preliminary, but fundamentally genic model provides quantitative support for some controversial qualitative claims regarding the evolutionary consequences of strong gene interactions made by opponents of genic selectionism, including Mayr''s theory of peripartric speciation. These findings foster hope that the proposed approach may eventually nudge the beanbag controversy out of its conceptual trenches into a more empirically oriented dialogue. (shrink)

Genic selectionism holds that all selection can be understood as operating on particular genes. Critics (and conventional biological wisdom) insist that this misrepresents the actual causal structure of selective phenomena at higher levels of biological organization, but cannot convincingly defend this intuition. I argue that the real failing of genic selectionism is pragmatic – it prevents us from adopting the most efficient corpus of causal laws for predicting and intervening in the course of affairs – and I offer (...) a Pragmatic account of causation itself which ultimately bears out the claim that genic selectionism misrepresents the causal structure of selective contexts. (shrink)

Proponents of genic selectionism have claimed that evolutionary processes normally viewed as selection on individuals can be "represented" as selection on alleles. This paper discusses the relationship between mathematical questions about the formal requirements upon state spaces necessary for the representation of different types of evolutionary processes and causal questions about the units of selection in such processes.

Contemporary biologists are not agreed on the question of whether there are any human races, despite the widespread scientific consensus on the underlying genetics. For most purposes, however, we can reasonably treat this issue as terminological. What most people in most cultures ordinarily believe about the significance of “racial” difference is quite remote, I think, from what the biologists are agreed on. Every reputable biologist will agree that human genetic variability between the populations of Africa or Europe or Asia is (...) not much greater than that within those populations; though how much greater depends, in part, on the measure of genetic variability the biologist chooses. If biologists want to make interracial difference seem relatively large, they can say that “the proportion of genic variation attributable to racial differences is … 9 – 11%.”1 If they want to make it seem small, they can say that, for two people who are both Caucasoid, the chances of difference in genetic constitution at one site on a given chromosome are currently estimated at about 14.3 percent, while for any two people taken at random from the human population, they are estimated at about 14.8 percent. The statistical facts about the distribution of variant characteristics in human populations and subpopulations are the same, whichever way the matter is expressed. Apart from the visible morphological characteristics of skin, hair, and bone, by which we are inclined to assign people to the broadest racial categories—black, white, yellow—there are few genetic characteristics to be found in the population of England that are not found in similar proportions in Zaire or in China; and few too which are found in Zaire but not in similar proportions in China or in England. All this, I repeat, is part of the consensus . A more familiar part of the consensus is that the differences between peoples in language, moral affections, aesthetic attitudes, or political ideology—those differences which most deeply affect us in our dealings with each other—are not biologically determined to any significant degree.[…]In this essay, I want to discuss the way in which W. E. B. Du Bois—who called his life story the “autobiography of a race concept”—came gradually, though never completely, to assimilate the unbiological nature of races. I have made these few prefatory remarks partly because it is my experience that the biological evidence about race is not sufficiently known and appreciated but also because they are important in discussing Du Bois. Throughout his life, Du Bois was concerned not just with the meaning of race but with the truth about it. We are more inclined at present, however, not to express our understanding of the intellectual development of people and cultures as a movement toward the truth; I shall sketch some of the reasons for this at the end of the essay. I will begin, therefore, by saying what I think the rough truth is about race, because, against the stream, I am disposed to argue that this struggle toward the truth is exactly what we find in the life of Du Bois, who can claim, in my view, to have thought longer, more engagedly, and more publicly about race than any other social theorist of our century. 1. Masatoshi Nei and Arun K. Roychoudhury, “Genetic Relationship and Evolution of Human Races,” Evolutionary Biology 14 : 11; all further references to this work, abbreviated “GR,” will be included in the text. Anthony Appiah is associate professor of philosophy, African studies, and Afro-American studies at Yale. He is the author of Assertion and Conditionals and For Truth in Semantics . In addition, he is at work on African Reflections: Essays in the Philosophy of Culture. (shrink)

Darwinians are realists about the force of selection, but there has been surprisingly little discussion about what form this realism should take. Arguments about the units of selection in general and genic selectionism in particular reveal two realist assumptions: (1) for any selection process, there is a uniquely correct identification of the operative selective forces and the level at which each impinges; and (2) selective forces must satisfy the Pareto-style requirement of probabilistic causation. I argue that both assumptions are (...) false; we must temper realism about the force of selection and revise the way we think about probabilistic causation. (shrink)

Health care is transitioning from genetics to genomics, in which single-gene testing for diagnosis is being replaced by multi-gene panels, genome-wide sequencing, and other multi-genic tests for disease diagnosis, prediction, prognosis, and treatment. This health care transition is spurring a new set of increased or novel liability risks for health care providers and test laboratories. This article describes this transition in both medical care and liability, and addresses 11 areas of potential increased or novel liability risk, offering recommendations to (...) both health care and legal actors to address and manage those liability risks. (shrink)

Sightings of the revolutionary comet that appeared in the skies of evolutionary biology in 1976—the selfish gene—date back to the 19th and early 20th centuries. It became generally recognized that genes were located on chromosomes and compete with each other in a manner consistent with the later appellation “selfish.” Chromosomes were seen as disruptable by the apparently random “cut and paste” process known as recombination. However, each gene was only a small part of its chromosome. On a statistical basis a (...) gene should escape disruption for many generations. This led George Williams and Richard Dawkins to a new definition of the gene, differing from conventional biochemical definitions in that there were no consistent genic boundaries. There had been no previous sightings of another revolutionary, albeit less verbally spectacular, comet that appeared in 1975—the homostability principle of Akiyoshi Wada. Each gene has a base composition “accent” that distinguishes it from its neighbors. We now see that recombination can be triggered by the shift in base composition at genic boundaries. Hence, the Williams-Dawkins definition approaches the conventional definitions. (shrink)

We may now ask the question: In what historical perspective should we place the work of Richard Goldschmidt? There is no doubt that in the period 1910–1950 Goldschmidt was an important and prolific figure in the history of biology in general, and of genetics in particular. His textbook on physiological genetics, published in 1938, was an amazing compendium of ideas put forward in the previous half-century about how genes influence physiology and development. His earlier studies on the genetic and geographic (...) distribution of the various species and races of Lymantria contributed soundly to an understanding of the inheritance and development of sex, as well as the genetics of speciation. He was a curious mixture of the experimentalist, empiricist, and theorizer, who could grasp both the large and the small at once and wrap them into the same integrated and coherent package.In insisting on trying to relate genetics to development, Goldschmidt was continually forced to speculate and to forsake experimental fact for generalized theory. In refusing to reconcile a physiological and developmental conception with a corpuscular theory of the gene, he forced himself to substitute for a large body of experimentally verified evidence, vague and general speculations which did not lead in any precise direction. L. C. Dunn summarizes succinctly the effect of Goldschmidt's thinking on the development of genetic theory: Although Goldschmidt's ideas had a considerable influence in directing attention to the developmental processes intervening between genes and characters, they did not lead to the establishment of a general theory of development in genetical terms. In fact, at the end of the period, as signalized by Goldschmidt's book of 1938 [Physiological Gentics] doubt remained whether there was a field with a defined problem which could be identified as developmental genetics.Yet the frequency with which Goldschmidt is cited by later writers suggests that there is a more positive side to his contribution than this. The early Mendelians had recognized the genic constitution of organisms and the Drosophila workers had uncovered in detail the chromosomal mechanism of heredity. These great discoveries were of classical character, solidly based on a multitude of well established facts. By themselves, however, they would not have been sufficient to place genetics in the central position within biology which it was to assume. Beyond the “static” analysis of gene transmission an insight was needed into the dynamic role of genes in cellular physiology, biochemistry, and development. Goldschmidt recognized this aspect and outlined in brilliant generalizations a physiological theory of genetics. Necessarily the prophetic nature of this achievement — romantic in the sense of Ostwald's classification of great scientists and their discoveries — transcended its factual basis. It was the audacity of the theoretician unimpeded by the still scanty data which gave a new focus to biological thought.Some have called Goldschmidt an “obstructionist” in the history of genetics—one whose efforts were largely directed toward useless and continual criticism — challenge for the sake of challenge. As this line of argument goes, time wasted answering Goldschmidt's poorly conceived criticisms could have been better used to pursue new lines of thought within the classical gene theory. Sometimes historians are upbraided for studying the work of such “obstructionists,” or even the work of those whose ideas have later proved to be inadequate. This argument misses the point of history and the lessons which it can teach. Perhaps Goldschmidt did take the time of a number of the classical geneticists who tried to answer his objections to the gene theory; and perhaps many of his own ideas about genes were, by today's view, “wrong.” These are always easier judgments to make by hindsight than at the moment. But that is not the point. Goldschmidt had a considerable influence on his contemporaries, and to dismiss him as an obstructionist because his opponents later proved to be more nearly right, distorts history and obscures significant questions which we might well be asking. It might be valuable to know why Goldschmidt felt compelled to be an iconoclast —and how that impulse, psychological in orgin, led him to overlook critical items of evidence which his opponents considered more carefully. It might also be valuable to try and understand how a contemporary of Goldschmidt or. Morgan really viewed the gene theory — what were its strong and weak point? Such questions are not readily answered by studying the work of only those men who were correct by later standards.Answers to some of the above questions can be gleaned from this study of Goldschmidt — though the first, and most psychologically oriented, question is largely untouched here.On the one hand, Goldschmidt forced classical geneticists to reexamine the foundation of their ideas about the nature, inviolability, and even physical dimensions of genes. He also kept alive the very real problems of gene physiology and its relations to development — a relationship that was given less attention by the Drosophila school in their pursuit of the transmission process. On a broader level he emphasized to the biological community a principle that was in danger of being lost in the enthusiasm surrounding the expansion of the Mendelian-chromosome theory. The point was that all theories in science are transient, logical constructs which should not be held as sacred. Time and again, as the history of science has shown, theories become rigid structures which retard new modes of thought. From Goldschmidt's perspective, the gene theory was in danger of performing just that function, for it was preventing workers from viewing the gene in a functional as well as a structural light.On the other hand, examining the work of critics (or even of outright “obstructionists”) gives the historian an opportunity to observe how the more established community of scholars at some point in time reacts to challenges of its cherished ideas. The fact that many workers in his own day (such as Beadle, Luria, Delbruck, Sturtevant, Bridges, and others), as well as most geneticists today, saw Goldschmidt as having been largely “obstructionist” is useful historical (and/or sociological) data. Clearly, as this paper has tried to show, Goldschmidt's ideas were not all obstructionist, and his viewpoint that genes must be considered functionally was one which was clearly valid, premature as it may have been from an experimental and technique point of view. Perhaps Goldschmidt's major fault was that he developed alternative theories which were not easily testable. Nonetheless, his challenge to a fundamental and established idea brought forth a reaction from many members of the genetic community which indicates how unwilling they were to reconsider the formalized theory on which their work was based. While many of Goldschmidt's criticisms — and particularly his way of making them — arose out of his own idiosyncrasies, they were also a product of his times. His view of the nature of theory-construction, and his rejection of old-style reductionism and mechanism, were part of a growing awareness within the world scientific community that explanations based on reducing complex phenomena to ultimate particles or units were clearly inadequate. The success of the Mendelian-chromosome theory had obscured that fact for many geneticists, but to Goldschmidt it was a point that could not be allowed to pass unnoticed. (shrink)

On the basis of distinctions between those properties of entities that can be defined without reference to other entities and those that (in different ways) cannot, this note argues that non-trivial forms of frequency-dependent selection of entities should be interpreted as selection occurring at a level higher than that of those entities. It points out that, except in degenerately simple cases, evolutionary game-theoretic models of selection are not models of individual selection. Similarly, models of genotypic selection such as heterosis cannot (...) be legitimately interpreted as models of genic selection. The analysis presented here supports the views that: (i) selection should be viewed as a multi-level process; (ii) upper-level selection is ubiquitous; (iii) kin selection should be viewed as a type of group selection rather than individual selection; and (iv) inclusive fitness is not an individual property. (shrink)

Sightings of the revolutionary comet that appeared in the skies of evolutionary biology in 1976—the selfish gene—date back to the 19th and early 20th centuries. It became generally recognized that genes were located on chromosomes and compete with each other in a manner consistent with the later appellation “selfish.” Chromosomes were seen as disruptable by the apparently random “cut and paste” process known as recombination. However, each gene was only a small part of its chromosome. On a statistical basis a (...) gene should escape disruption for many generations. This led George Williams and Richard Dawkins to a new definition of the gene, differing from conventional biochemical definitions in that there were no consistent genic boundaries. There had been no previous sightings of another revolutionary, albeit less verbally spectacular, comet that appeared in 1975—the homostability principle of Akiyoshi Wada. Each gene has a base composition “accent” that distinguishes it from its neighbors. We now see that recombination can be triggered by the shift in base composition at genic boundaries. Hence, the Williams-Dawkins definition approaches the conventional definitions. (shrink)

Sober and Lewontin's critique of genic selectionism is based upon the principle that a unit of selection should make a context‐independent contribution to fitness. Critics have effectively shown that this principle is flawed. In this paper I show that the context independence principle is an instance of a more general principle for characterizing causes,called the contextual unanimity principle. I argue that this latter principle, while widely accepted, is erroneous. What is needed is to replace the approach to causality characterized (...) by the contextual unanimity criterion with an approach based on the concept of causal mechanism. After sketching such an approach, I show how it can be used to shed light on the units of selection problem. (shrink)

It is tempting to invoke organismal selection as perpetually optimizing the function of any given gene. However, natural selection can drive genic functional change without improvement of biochemical activity, even to the extinction of gene activity. Detrimental mutations can creep in owing to linkage with other selectively favored loci. Selection can promote functional degradation, irrespective of genetic drift, when adaptation occurs by loss of gene function. Even stabilizing selection on a trait can lead to divergence of the underlying molecular (...) constituents. Selfish genetic elements can also proliferate independent of any functional benefits to the host genome. Here we review the logic and evidence for these diverse processes acting in genome evolution. This collection of distinct evolutionary phenomena – while operating through easily understandable mechanisms – all contribute to the seemingly counterintuitive notion that maintenance or improvement of a gene's biochemical function sometimes do not determine its evolutionary fate. (shrink)

Uniformitarianism is a dual concept. Substantive uniformitarianism (a testable theory of geologic change postulating uniformity of rates or material conditions) is false and stifiqng to hypothesis formation. Methodological uniformitarianism (a procedural principle asserting spatial and temporal invariance of natural laws) belongs to the definition of science and is not unique to genic~~. Methodological uniformitarianism enabled Lyell to exclude the miraculous from geologic explanation; its invocation today is anachronistic since the question of divine intervention is no longer an issue in (...) science. Substantive uniformitarianism, an incorrect theory, should be abandoned. Methodological uniformitarianism, now a superfiuous term, is best confined to the past history of geology. (shrink)

In a recent article, Kim Sterelny and Philip Kitcher5 defend a version of genic selectionism and attempt to refute the criticisms I made of that doctrine. Their defense has two components. First, they find fault with the account I gave of the units-of-selection controversy-an account which uses the idea of probabilistic causality as a tool of explication. Second, they provide a positive account of their own of what that controversy concerns, one which they think allows genic selectionism to (...) emerge as a successful thesis. I believe that the position they sketch is mistaken, both in its general orientation and in its details. I believe that the Sterelny/ Kitcher position misunderstands what the biological question of the units of selection is about and that their criticisms of my own proposal are mistaken as well. (shrink)

Cracks in the one‐gene, one‐band paradigm for polytene chromosome organization are widening. At the same time evidence is accumulating suggesting that decondensed regions of the chromosomes (puffs, diffuse bands, interbands and possibly vacuoles within some bands) are generally associated with gene transcription. A model, now on the ascendancy, is based on the proposal that the band‐interband pattern is primarily a reflection of local transcriptional state, rather than the distribution of genic and non‐genic material.

The greatest diversity of butterflies and their host plants occurs in tropical regions. Some groups of butterflies in the tropics exhibit monophagous feeding in the larval stage, exploiting only one family of plants; others are polyphagous, feeding on plants in two or more distinct families. The two major types of tropical habitats for butterflies, namely primary and secondary forests, offer very different evolutionary opportunities for the exploitation of plants as larval food. Butterflies are faced with the major logistical problem, as (...) are many other herbivorous insects, of depositing eggs on the correct plant for successful larval feeding. This paper, using the concepts of phenotype set and spatial patchiness of resources, attemps to make some predictions as to the optimal phenotypic systems for monophagous and polyphagous feeding in tropical butterflies, as related to the spatial patchiness of larval host plants in primary and secondary forests. In addition to the secondary compound chemistry of larval host plants as playing a role in the evolution of monophagy and polyphagy, the assumption is made that the spatial patchiness of host plants within and among different families also acts as a major factor in determining optimal ranges of phenotypes for different patterns of larval feeding. Owing to the high spatial patchiness of primary forest species of canopy trees and vines, it is predicted that butterflies exploiting these will be mostly polyphagous, whereas secondary forests having stable formations of fewer plant species and larger patches of these plants, will have mostly monophagous species. Forest understories may have both monophagous and polyphagous species, depending upon the layer of forest and the general type of understory (i.e. palmaceous or dicotyledonous). Field data on some groups of butterflies from tropical America support these predictions. Polyphagous butterflies are predicted to possess a genetic system of mixed morphs with a population being polymorphic as a whole; monophagous butterflies are predicted to have individuals all more or less similar genetically, and with a high amount of genic variation within individuals. Other forms of monophagy may evolve in species that are essentially monomorphic but with various mechanisms (physiological, developmental, behavioral) of phenotypic flexibility at the individual level. Although the environment is essentially coarse-grained for larvae since most are sedentary and polymorphism is an optimal adaptive strategy, the oviposition strategy of the adult must also be considered and some situations (i.e. forest canopy) have resources (host plants) distributed in a fine-grained fashion. Other forms of limited polyphagy may result from monomorphic genetic systems in which there is considerable phenotypic flexibility. (shrink)

Four years after the death of Charles Darwin, his research associate, George Romanes, invoked a mysterious process—“physiological selection”—that could often have secured reproductive isolation independently of, and prior to, natural selection, so leading to an origin of species. This postulate of two sequential selection modes can now be regarded as leading to modern “chromosomal,” as opposed to “genic,” speciation theories. Romanes’ abstractions—which confounded many, but not all, of his contemporaries—equate with divergences in parental DNA sequences that impede meiotic pairing (...) in their hybrid offspring, so rendering that offspring sterile. Unlike Darwin, Romanes saw hybrid sterility as a parental, rather than offspring, phenotype that would, within a species, reproductively isolate certain parents from each other while not impeding their crossing with other parents. This group selection would have empowered natural selection to act more advantageously than in its absence. Given suitable conditions, there could then be divergence from one species into two. The present essay introduces Romanes’ “Physiological Selection; an Additional Suggestion on the Origin of Species” 19:337–411; available as supplementary material in the online version of this essay) for the journal’s “Classics in Biological Theory” collection. (shrink)

I discuss two subjects in Samir Okasha’s excellent book, Evolution and the Levels of Selection. In consonance with Okasha’s critique of the conventionalist view of the units of selection problem, I argue that conventionalists have not attended to what realists mean by group, individual, and genic selection. In connection with Okasha’s discussion of the Price equation and contextual analysis, I discuss whether the existence of these two quantitative frameworks is a challenge to realism.

Wim van der Steen charts conceptual foundations of evolutionary biology and, on the basis of this, he evaluates applications of evolutionary theory outside biology. Philosophical analysis shows that key notions of the theory such as fitness, adaptation, selection, and optimality are empty place-holder concepts that call for context-dependent specifications of meaning. For example, as he points out, the notion of optimality is empty without a specification of constraints. Hence, the controversial thesis that animals perform optimal behaviors as a result of (...) natural selection is meaningless rather than true or false. Analysis shows that many other controversies in evolutionary biology are spurious. Thus, the thesis of genic selectionism, which puts genes at center stage in evolutionary theory, is best reconstructed as an arbitrary conceptualization without substance. Disagreements over the thesis are futile. They reflect preferences for different conceptualizations which are ultimately equivalent. As concepts are properly specified, van der Steen asserts evolutionary theory turns out to be a body of interesting natural history at a low level of generality. General laws of evolution do not exist. Hence, evolutionary approaches do not allow sweeping claims about human nature. Unfortunately, in disciplines outside biology such claims are often defended with evolutionary approaches. Evolutionary theory also cannot serve as a foundation for normative views in ethics or epistemology. This is an important and controversial work for scholars and advanced researchers in biology and the philosophy of biology. (shrink)

This chapter surveys the philosophical problems raised by the two Darwinian claims of the existence of a Tree of a life, and the explanatory power of natural selection. It explores the specificity of explanations by natural selection, emphasizing the high context-dependency of any process of selection. Some consequences are drawn about the difficulty of those explanations to fit a nomological model of explanation, and the irreducibility of their historic-narrative dimension. The paper introduces to the debates about units of selection, stating (...) the compelling force of genic selectionnism but highlighting some critiques. Then it addresses the limits of selectionist explanations : the compared status of selection, drift and phylogenetic inertia are investigated, and the debates over adaptationism are presented, with the aim of defining the varieties of adaptationisms as research programs. In order to assess the scope of natural selection, the chapter addresses weak and strong challenges to the Synthetic theory of evolution, both from paleontology (punctuated equilibria, Gould’s contingency thesis) and evolutionary theory of development. We finally sketch some consequences of evolutionary theory concerning philosophical questions about human nature, on the basis of the hypothesis of the universality of selectionist explanations: this part deals mostly with epistemology and psychology. (shrink)

Since the fundamental challenge that I laid at the doorstep of the pluralists was to defend, with nonderivative models, a strong notion of genic cause, it is fatal that Waters has failed to meet that challenge. Waters agrees with me that there is only a single cause operating in these models, but he argues for a notion of causal ‘parsing’ to sustain the viability of some form of pluralism. Waters and his colleagues have some very interesting and important ideas (...) about the sciences, involving pluralism and parsing or partitioning causes, but they are ideas in search of an example. He thinks he has found an example in the case of hierarchical and genic selection. I think he has not. (shrink)

I argue that four of the fundamental claims of those calling themselves `genic pluralists'Philip Kitcher, Kim Sterelny, and Ken Watersare defective. First, they claim that once genic selectionism is recognized, the units of selection problems will be dissolved. Second, Sterelny and Kitcher claim that there are no targets of selection. Third, Sterelny, Kitcher, and Waters claim that they have a concept of genic causation that allows them to give independent genic causal accounts of all selection processes. (...) I argue that each one of these claims is either false or misleading. Moreover, the challenge that arises from the availability of genic causal accounts, namely, the inability to choose on rational grounds among genic and higher-level accounts, is unsupported. (shrink)

The discussion with Rao and Nanjundiah about the history of interactions between J. B. S. Haldane and Ernst Mayr is further extended in this note. The nature of the dispute about beanbag genetics is explicated as consisting of two separate issues, one about the role of mathematical analysis in evolutionary biology, and the other about the value of single-locus genic models.

Biologists often define evolution as a change in allele frequencies. Consideration of the evolution of the pocket mouse will show that it is possible to have evolution without any change in the allele frequencies in a population (through change in the genotype frequencies). The implications of this for genic selectionism are then discussed. Sober and Lewontin (1982) have constructed an example to demonstrate the blindness of genic selectionism in certain cases. Sterelny and Kitcher (1988) offer a defense against (...) these arguments which assumes a conventionalist approach to populations. The example considered here will be shown to offer a more plausible and far-reaching argument against the view that alleles can always be seen as the units of selection. (shrink)

Eugenics is commonly thought of as having endured as science and social movement only until 1945. With the advance of both reproductive and enhancement technologies, however, concern has arisen that eugenics has resurfaced in new forms. In particular, the eugenic potential of the Human Genome Project led to talk of the rise of ‘newgenics’ and of a backdoor to eugenics. This article focuses on such concerns deriving from the practice of prenatal screening and technologies that increase our ability to generate (...) information about the kinds of children we are likely to have. Given individual preferences and social norms concerning what traits are intergenerationally desirable, how should we act and what practices and policies should we endorse or scrutinise? This article will concentrate on key components of eugenic thinking present today and emphasise continuities between the eugenic past and new- genic present in the subhumanisation of people with cognitive or intellectual disabilities. (shrink)

Most models of generational succession in sexually reproducing populations necessarily move back and forth between genic and genotypic spaces. We show that transitions between and within these spaces are usually hidden by unstated assumptions about processes in these spaces. We also examine a widely endorsed claim regarding the mathematical equivalence of kin-, group-, individual-, and allelic-selection models made by Lee Dugatkin and Kern Reeve. We show that the claimed mathematical equivalence of the models does not hold. *Received January 2007; (...) revised April 2008. †To contact the authors, please write to: Elisabeth Lloyd, Department of History and Philosophy of Science, 130 Goodbody Hall, Indiana University, Bloomington, IN 47405; e-mail: [email protected]; Richard Lewontin, Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, MA 02138; Marcus Feldman, Department of Biological Sciences, Stanford University, Stanford, CA 94305; e-mail: [email protected]. (shrink)

Most models of generational succession in sexually reproducing populations necessarily move back and forth between genic and genotypic spaces. We show that transitions between and within these spaces are usually hidden by unstated assumptions about processes in these spaces. We also examine a widely endorsed claim regarding the mathematical equivalence of kin-, group-, individual-, and allelic-selection models made by Lee Dugatkin and Kern Reeve. We show that the claimed mathematical equivalence of the models does not hold.

One of the most interesting challenges facing paleobiologists is explaining the Cambrian explosion, the dramatic appearance of most metazoan animal phyla in the Early Cambrian, and the subsequent stability of these body plans over the ensuing 530 million years. We propose that because phenotypic variation decreases through geologic time, because microRNAs (miRNAs) increase genic precision, by turning an imprecise number of mRNA transcripts into a more precise number of protein molecules, and because miRNAs are continuously being added to metazoan (...) genomes through geologic time, miRNAs might be instrumental in the canalization of development. Further, miRNAs ultimately allow for natural selection to elaborate morphological complexity, because by reducing gene expression variability, miRNAs increase heritability, allowing selection to change characters more effectively. Hence, miRNAs might play an important role in shaping metazoan macroevolution, and might be part of the solution to the Cambrian conundrum. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:The Human Genome ProjectSharon J. Durfy (bio) and Amy E. Grotevant (bio)In recent years, scientists throughout the world have embarked upon a long-term biological investigation that promises to revolutionize the decisions people make about their lives and lifestyles, the way doctors practice medicine, how scientists study biology, and the way we think of ourselves as individuals and as a species. It is called the Human Genome Project, and its (...) ultimate goal is to map and determine the chemical sequence of the three billion nucleotide base pairs that comprise the human genome. The feat is expected to take about fifteen years (see General Surveys).These three billion base pairs include an estimated 50,000 to 100,000 genes. The rest of the genome—perhaps 95 percent of it—is nongenic sequences with unknown function, sometimes called "junk." Determining the order and organization of all this material has been likened to tearing six volumes of the Encyclopaedia Brittanica into pieces, then trying to put it all back together to read the information (Surveys: Hall 1990). The effort could be well worth it, many scientists say, because it is expected to yield major insights into many common and complex diseases, including cancer, cardiovascular disease, and Alzheimer's disease (Debate: Dulbecco 1986; Koshland 1989).The Human Genome Project is not without controversy, however (Debate: Davis 1990; Leder 1990; Rechsteiner 1990). Many scientists fear that funding for it will be diverted from other areas of research, rather than obtained from new funding sources. This has enlivened the debate about the relative value of "big" versus "small" science. Also, the value of undertaking a complete sequencing of the genome has been questioned, especially given the high proportion of non-genic sequences.Advocates of the effort converted many critics by making two alterations in the original plan. Plans were included to simultaneously determine the nucleotide sequence of the genomes of other organisms; this provides comparisons and points of reference for the human sequence (U.S.: NIH/DOE 1990). Second, in response to concerns about the high cost of developing technology to sequence the whole [End Page 347] genome, the focus moved from large-scale sequencing to mapping the genome, which would hasten the search for disease genes (U.S.: NIH/DOE 1990).The ideal map would be both genetic, locating DNA markers, or signposts, at closely spaced intervals along the chromosomes, and physical, indicating the exact distance between these markers (Map: McKusick 1991). Since 1973, Human Gene Mapping workshops (HGM) have been held at least every two years to locate, compare, and compile genetic markers. This information is published and is accessible through Genome Database at Johns Hopkins University (McKusick 1991). The most recent Human Genome Mapping workshop was held in August 1991, at which the Human Genome Organization (HUGO) began to assume increased responsibility for coordination of the international mapping effort (Surveys: Maddox 1991).Historical Background of the United States EffortThe first serious discussions about sequencing the entire human genome occurred at a workshop at the University of California at Santa Cruz in 1985 (U.S.: Sinsheimer 1989). A second workshop, organized by the U.S. Department of Energy (DOE) and held in March 1986, addressed the feasibility of an organized program (U.S.: DOE 1986). Shortly thereafter, DOE instituted its own genome project (U.S.: DOE 1987). Reports in early 1988 from both the National Research Council (NRC) of the National Academy of Sciences (NAS) and Congress' Office of Technology Assessment (OTA) (U.S.: NRC 1988; OTA 1988) served as catalysts, and in fiscal year 1988, the U.S. Congress officially launched the Human Genome Project by appropriating funds to both the Department of Energy and the National Institutes of Health (NIH).To avoid potential congressional "meddling" (U.S.: Roberts 1988), NIH and DOE drafted a memorandum of understanding for interagency coordination in October 1988 (U.S.: NIH/DOE 1990). The agencies then created both separate and joint committees, and working groups to administer the project. NIH established the Office of Human Genome Research in 1988 (directed by James D. Watson) to plan and coordinate NIH genome activities. That office has evolved into the National Center for Human Genome Research (NCHGR... (shrink)

In humans over 15% of X‐linked genes have been shown to ‘escape’ from X‐chromosome inactivation (XCI): they continue to be expressed to some extent from the inactive X chromosome. Mono‐allelic expression is anticipated within a cell for genes subject to XCI, but random XCI usually results in expression of both alleles in a cell population. Using a study of allelic expression from cultured lymphoblasts and fibroblasts, many of which showed substantial skewing of XCI, we recently reported that the expression of (...) genes lies on a contiunuum between those that are subject to inactivation, and those that escape. We now review allelic expression studies from mouse, and discuss the variability in escape seen in both humans and mice in genic expression levels, between X chromosomes and between tissues. We also discuss current knowledge of the heterochromatic features, DNA elements and three‐dimensional topology of the inactive X that contribute to the balance of expression from the otherwise inactive X chromosome. (shrink)

Invested with the capacity to reinstate physiological order, medicines are at the centre of contemporary health care. Their purpose and efficacy are generally seen as predictable and concrete: disease = therapy = outcome. These culturally specific understandings shape the practices and meanings of taking medicines. This article, however, queries what actually takes place when human bodies and medical drugs converge. Is it a solely therapeutic affair, a restoration of bodily normality, or one of multiple transformations? The ambivalent meaning of the (...) original Greek word for drug, pharmakon, intimates the potential of medicines to act as ‘remedy’ as well as ‘poison’. Using pharmakon as a conceptual tool, the article explores the complex, and often paradoxical corporeal effects of HIV combination therapy, with particular focus on lipodystrophy, a peculiar change in people‘s body shape. This unintended and frequently distressing iatro-genic phenomenon challenges common notions of therapeutic efficacy and causality and foregrounds the productive dimension of medical drugs - their capacity to reconfigure bodies, diseases and identities in multiple, unpredictable ways. (shrink)