Although epistasis is at the center of the Fisher-Wright debate, biologists not involved in the controversy are often unaware that there are actually two different formal definitions of epistasis. We compare concepts of genetic independence in the two theoretical traditions of evolutionary genetics, population genetics and quantitative genetics, and show how independence of gene action (represented by the multiplicative model of population genetics) can be different from the absence of gene interaction (represented by the linear additive model of quantitative genetics). (...) The two formulations converge with weak selection but not with strong selection or, for multiple loci, when the aggregated interaction terms are not negligible. As a result of the different formulations of gene interaction, the presence or absence of linkage disequilibrium,/D/, does not necessarily indicate the presence or absence of fitness epistasis. Indeed, linkage disequilibrium is generated in ‘additive’ models in quantitative genetics whenever two (or more) loci experience simultaneous selection. As a research strategy, it is often practical, for theoretical or experimental reasons, to minimize gene interaction by assuming independence of gene action in regard to fitness, or by assuming linear additive effects of multiple loci on a phenotype. However, minimizing the role of epistasis in theoretical investigations hinders our understanding of the origins of diversity and the evolution of complex phenotypes. (shrink)

We develop an account of laboratory models, which have been central to the group selection controversy. We compare arguments for group selection in nature with Darwin's arguments for natural selection to argue that laboratory models provide important grounds for causal claims about selection. Biologists get information about causes and cause-effect relationships in the laboratory because of the special role their own causal agency plays there. They can also get information about patterns of effects and antecedent conditions in nature. But to (...) argue that some cause is actually responsible in nature, they require an inference from knowledge of causes in the laboratory context and of effects in the natural context. This process, cause detection, forms the core of an analogical argument for group selection. We discuss the differing roles of mathematical and laboratory models in constructing selective explanations at the group level and apply our discussion to the units of selection controversy to distinguish between the related problems of cause determination and evaluation of evidence. Because laboratory models are at the intersection of the two problems, their study is crucial for framing a coherent theory of explanation for evolutionary biology. (shrink)

Gene drives are selfish genetic elements that use a variety of mechanisms to ensure they are transmitted to subsequent generations at greater than expected frequencies. Synthetic gene drives based on the clustered regularly interspersed palindromic repeats genome editing system have been proposed as a way to alter the genetic characteristics of natural populations of organisms relevant to the goals of public health, conservation, and agriculture. Here, we review the principles and potential applications of CRISPR drives, as well as means proposed (...) to prevent their uncontrolled spread. We also focus on recent work suggesting that factors such as natural genetic variation and inbreeding may represent substantial impediments to the propagation of CRISPR drives. CRISPR-based synthetic selfish genetic elements, or gene drives, have been proposed as a means by which to genetically alter natural populations to address issues in agriculture, conservation, and public health. We describe key concepts of CRISPR gene drives and limitations that must be addressed before their use in the wild. (shrink)

We address the controversy in the literature concerning the definition of holobionts and the apparent constraints on their evolution using concepts from community population genetics. The genetics of holobionts, consisting of a host and diverse microbial symbionts, has been neglected in many discussions of the topic, and, where it has been discussed, a gene-centric, species-centric view, based in genomic conflict, has been predominant. Because coevolution takes place between traits or genes in two or more species and not, strictly speaking, between (...) species, it may affect some traits but not others in either host or symbiont. Moreover, when interacting species pairs are embedded in a larger community, indirect ecological effects can alter the expected pairwise dynamics. Mode of symbiont transmission and the degree of host inbreeding both affect the extent of microbial mixing across host lineages and thereby the degree to which selection on one trait of either partner affects other aspects of a holobiont phenotype. We discuss several potential defining criteria for holobionts using community genetics and population genetics models, suggesting their application and limitations. Using community genetics models, we show how conflict between genomes can be self-limiting, while cooperation and mutualism tend to be self-accelerating. It is likely that this bias in the evolutionary dynamics of interaction between hosts and symbionts is an important feature of holobionts. This bias in the evolutionary dynamic could contribute to explaining the absence of cheaters from natural mutualisms, although cheaters are predicted by gene-centered conflict theory to cause the evolutionary instability of mutualisms. Additionally, it may help explain the more frequent origin of mutualisms from parasitic than from free-living systems, an evolutionary trajectory opposite to that predicted by genome conflict theory. (shrink)

Since Darwin, there has been a long and arduous struggle to understand the source and maintenance of natural genetic variation and its relationship to phenotype. The reason that this task is so difficult is that it requires integration of detailed, and as yet incomplete, knowledge from several biological disciplines, including evolutionary, population, and developmental genetics. In this ‘post‐genomic’ era, it is relatively easy to identify differences in the DNA sequence between individuals. However, the task remains to delineate how this abundant (...) genetic diversity actually contributes to phenotypic diversity. This necessitates tackling the problem of hidden genetic variation. Genetic polymorphisms can be conditionally cryptic, but have the potential to contribute to phenotypic variation in particular genetic backgrounds or under specific environmental conditions. A recent paper by Lauter and Doebley highlights the contribution of hidden genetic variation to traits characterizing the morphological evolution of modern maize from its wild grass‐like progenitor teosinte.1 This work is the first to demonstrate hidden variance for selected (agronomically ‘adaptive’) traits in a well‐characterized model for morphological evolution. BioEssays 24:685–689, 2002. © 2002 Wiley Periodicals, Inc. (shrink)

In a previous study, using experimental metapopulations of the flour beetle, Tribolium castaneum, we investigated phase III of Wright's shifting balance process (Wade and Griesemer 1998). We experimentally modeled migration of varying amounts from demes of high mean fitness into demes of lower mean fitness (as in Wright's characterization of phase III) as well as the reciprocal (the opposite of phase III). We estimated the meta-populational heritability for this level of selection by regression of offspring deme means on the (...) weighted parental deme means.Here we develop a Punnett Square representation of the inheritance of the group mean to place our empirical findings in a conceptual context similar to Mendelian inheritance of individual traits. The comparison of Punnett Squares for individual and group inheritance shows how the latter concept can be rigorously defined and extended despite the lack of explicitly formulated, simple Mendelian laws of inheritance at the group level. Whereas Wright's phase III combines both interdemic selection and meta-populational inheritance, our formulation separates the issue of meta-populational heritability from that of interdemic selection. We use this conceptual context to discuss the controversies over the levels of selection and the units of inheritance. (shrink)

Two controversies exist regarding the appropriate characterization of hierarchical and adaptive evolution in natural populations. In biology, there is the Wright-Fisher controversy over the relative roles of random genetic drift, natural selection, population structure, and interdemic selection in adaptive evolution begun by Sewall Wright and Ronald Aylmer Fisher. There is also the Units of Selection debate, spanning both the biological and the philosophical literature and including the impassioned group-selection debate. Why do these two discourses exist separately, and interact relatively little? (...) We postulate that the reason for this schism can be found in the differing focus of each controversy, a deep difference itself determined by distinct general styles of scientific research guiding each discourse. That is, the Wright-Fisher debate focuses on adaptive process, and tends to be instructed by the mathematical modeling style, while the focus of the Units of Selection controversy is adaptive product, and is typically guided by the function style. The differences between the two discourses can be usefully tracked by examining their interpretations of two contested strategies for theorizing hierarchical selection: horizontal and vertical averaging. (shrink)

Adaptive phenotypic plasticity allows organisms to cope with environmental variability, and yet, despite its adaptive significance, phenotypic plasticity is neither ubiquitous nor infinite. In this review, we merge developmental and population genetic perspectives to explore costs and limits on the evolution of plasticity. Specifically, we focus on the role of modularity in developmental genetic networks as a mechanism underlying phenotypic plasticity, and apply to it lessons learned from population genetic theory on the interplay between relaxed selection and mutation accumulation. We (...) argue that the environmental specificity of gene expression and the associated reduction in pleiotropic constraints drive a fundamental tradeoff between the range of plasticity that can be accommodated and mutation accumulation in alternative developmental networks. This tradeoff has broad implications for understanding the origin and maintenance of plasticity and may contribute to a better understanding of the role of plasticity in the origin, diversification, and loss of phenotypic diversity. (shrink)

Late in 1990, the Center for the Study of Ethics in the Professions at Illinois Institute of Technology (lIT) received a grant of more than $200,000 from the National Science Foundation to try a campus-wide approach to integrating professional ethics into its technical curriculum.! Enough has now been accomplished to draw some tentative conclusions. I am the grant's principal investigator. In this paper, I shall describe what we at lIT did, what we learned, and what others, especially philosophers, can learn (...) from us. We set out to develop an approach that others could profitably adopt. I believe that we succeeded. (shrink)

Moral sensitivity affects whether and how we see others, note moral concerns, respond with delicacy, and navigate complex social interactions. Scholars from a variety of fields explore the concept of moral sensitivity and how it develops, beginning with a natural moral capacity for sensitivity towards others that is shaped in a variety of ways through relationships, forms of teaching, and social institutions. Each of these influences alters the capacity as well as one’s responses in complex ways. The concept of moral (...) sensitivity deepens as progressive chapters demonstrate its increasing complexity through development within individuals, over time, as they mature, and as their relationships and social contexts expand. The chapters integrate research from philosophy, psychology, neuroscience, literature, education, and media and technology studies, with key chapters by Darcia Narváez, Nancy E. Snow, Michael S. Pritchard, and Stephen J. Thoma and a Foreword by Owen Flanagan. It is the only comprehensive presentation of interdisciplinary work on moral sensitivity that integrates a theoretical, methodological, and pedagogical analysis. This highly interdisciplinary approach provides a new way of thinking about the relationship of individuals to society and moral sensitivity as a social phenomenon, extending current research in ethics, moral psychology, and psychology toward situated, embodied, and contextual analyses. (shrink)

An Essay on Human Action seeks to provide a comprehensive, detailed, enlightening, and (in its detail) original account of human action. This account presupposes a theory of events as abstract, proposition-like entities, a theory which is given in the first chapter of the book. The core-issues of action-theory are then treated: what acting in general is (a version of the traditional volitional theory is proposed and defended); how actions are to be individuated; how long actions last; what acting intentionally is; (...) what doing one thing by doing another is; what basic action is; and what omitting to do something is. Attention is also given to the concepts of causation, intention, volition, deciding, choosing, and trying. Finally, a libertarian account of free action is tentatively proposed and defended. (shrink)

Every choice we make is set against a background of massive ignorance about our past, our future, our circumstances, and ourselves. Philosophers are divided on the moral significance of such ignorance. Some say that it has a direct impact on how we ought to behave - the question of what our moral obligations are; others deny this, claiming that it only affects how we ought to be judged in light of the behaviour in which we choose to engage - the (...) question of what responsibility we bear for our choices. Michael Zimmerman claims that our ignorance has an important bearing on both questions, and offers an account of moral obligation and moral responsibility that is sharply at odds with the prevailing wisdom. His book will be of interest to a wide range of readers in ethics. (shrink)

The principal aim of this book is to develop and defend an analysis of the concept of moral obligation. The analysis is neutral regarding competing substantive theories of obligation, whether consequentialist or deontological in character. What it seeks to do is generate solutions to a range of philosophical problems concerning obligation and its application. Amongst these problems are deontic paradoxes, the supersession of obligation, conditional obligation, prima facie obligation, actualism and possibilism, dilemmas, supererogation, and cooperation. By virtue of its normative (...) neutrality, the analysis provides a theoretical framework within which competing theories of obligation can be developed and assessed. This study is a major contribution to metaethics that will be of particular interest to all philosophers concerned with normative ethical theory. (shrink)

This superbly crafted account of the notion of moral responsibility and of its relations to freedom, control, ignorance, negligence, attempts, omissions, compulsion, mental disorders, virtues and vices, desert, and punishment fills that gap. The treatment of character and luck is particularly sophisticated and well-argued.

Michael J. Zimmerman explores whether and how our ignorance about ourselves and our circumstances affects what our moral obligations and moral rights are. He rejects objective and subjective views of the nature of moral obligation, and presents a new case for a 'prospective' view.

Intrinsic value has traditionally been thought to lie at the heart of ethics. Philosophers use a number of terms to refer to such value. The intrinsic value of something is said to be the value that that thing has “in itself,” or “for its own sake,” or “as such,” or “in its own right.” Extrinsic value is value that is not intrinsic.

What's wrong with designer children, bionic athletes, and genetic engineering.

Introduction: Doing the right thing -- Utilitarianism : Bentham and J.S. Mill -- Libertarianism -- John Locke -- Markets and morals -- Immanuel Kant -- John Rawls -- Affirmative action -- Aristotle -- Liberals and communitarians -- Conclusion: Reconnecting politics and morals.

In _The Immorality of Punishment_ Michael Zimmerman argues forcefully that not only our current practice but indeed any practice of legal punishment is deeply morally repugnant, no matter how vile the behaviour that is its target. Despite the fact that it may be difficult to imagine a state functioning at all, let alone well, without having recourse to punishing those who break its laws, Zimmerman makes a timely and compelling case for the view that we must seek and put (...) into practice alternative means of preventing crime and promoting social stability. (shrink)

Preface In these days, an anthology on the topic of possible worlds hardly needs justification. No issue has given rise to as much literature in the past ...

There is currently an explosion of interest in grounding. In this article we provide an overview of the debate so far. We begin by introducing the concept of grounding, before discussing several kinds of scepticism about the topic. We then identify a range of central questions in the theory of grounding and discuss competing answers to them that have emerged in the debate. We close by raising some questions that have been relatively neglected but which warrant further attention.

_Metaphysics: A Contemporary Introduction_ is for students who have already completed an introductory philosophy course and need a fresh look at the central topics in the core subject of metaphysics. It is essential reading for any student of the subject. This Fourth Edition is revised and updated and includes two new chapters on Parts and Wholes, and Metaphysical Indeterminacy or vagueness. This new edition also keeps the user-friendly format, the chapter overviews summarizing the main topics, concrete examples to clarify difficult (...) concepts, annotated further reading at the end of each chapter, endnotes, and a full bibliography. Topics addressed include: the problem of universals the nature of abstract entities the problem of individuation the nature of modality identity through time the nature of time the nature of parts and wholes the problem of metaphysical indeterminacy the Realism/anti-Realism debate. Wherever possible, Michael J. Loux and Thomas M. Crisp relate contemporary views to their classical sources in the history of philosophy. As experienced teachers of philosophy and important contributors to recent debates, Loux and Crisp are uniquely qualified to write this book. (shrink)

In this book, Michael Sandel takes up some of the hotly contested moral and political issues of our time, including affirmative action, assisted suicide, ...

At the heart of ethics reside the concepts of good and bad; they are at work when we assess whether a person is virtuous or vicious, an act right or wrong, a decision defensible or indefensible, a goal desirable or undesirable. But there are many varieties of goodness and badness. At their core lie intrinsic goodness and badness, the sort of value that something has for its own sake. It is in virtue of intrinsic value that other types of value (...) may be understood, and hence that we can begin to come to terms with questions of virtue and vice, right and wrong, and so on. This book investigates the nature of intrinsic value: just what it is for something to be valuable for its own sake, just what sort of thing can have such value, just how such a value is to be computed. In the final chapter, the fruits of this investigation are applied to a discussion of pleasure, pain, and displeasure and also of moral virtue and vice, in order to determine just what value lies within these phenomena. (shrink)

Problems of and explanations for evil -- Neo-cartesianism -- Animal suffering and the fall -- Nobility, flourishing, and immortality : animal pain and animal well-being -- Natural evil, nomic regularity, and animal suffering -- Chaos, order, and evolution -- Combining CDs.

In this paper we discuss ethical implications of the use of mobile phone apps in the control of the COVID-19 pandemic. Contact tracing is a well-established feature of public health practice during infectious disease outbreaks and epidemics. However, the high proportion of pre-symptomatic transmission in COVID-19 means that standard contact tracing methods are too slow to stop the progression of infection through the population. To address this problem, many countries around the world have deployed or are developing mobile phone apps (...) capable of supporting instantaneous contact tracing. Informed by the on-going mapping of ‘proximity events’ these apps are intended both to inform public health policy and to provide alerts to individuals who have been in contact with a person with the infection. The proposed use of mobile phone data for ‘intelligent physical distancing’ in such contexts raises a number of important ethical questions. In our paper, we outline some ethical considerations that need to be addressed in any deployment of this kind of approach as part of a multidimensional public health response. We also, briefly, explore the implications for its use in future infectious disease outbreaks. (shrink)

Both fairness and efficiency are important considerations in market design and regulation, yet many regulators have neither defined nor measured these concepts. We develop an evidencebased policy framework in which these are both defined and measured using a series of empirical proxies. We then build a systems estimation model to examine the 2003–2011 explosive growth in algorithmic trading on the London Stock Exchange and NYSE Euronext Paris. Our results show that greater AT is associated with increased transactional efficiency and reduced (...) information leakage in top quintile stocks. For less liquid stocks, manipulation at the close declines. We also document the tradeoff between reduced spreads and increased manipulation or information leakage following the introduction of MiFID1. (shrink)

_The Metaphysics of Perfect Beings_ addresses the problems an Anselmian perfect being faces in contexts involving unlimited options. Recent advances in the theory of vagueness, the metaphysics of multiverses and hyperspace, the theory of dynamic or sequential choice, the logic of moral and rational dilemmas, and metaethical theory provide the resources to formulate the new challenges and the Anselmian responses with an unusual degree of precision. Almeida shows that the challenges arising in the unusual contexts involving unlimited options sometimes produce (...) metaphysical surprise. (shrink)

Bringing together researchers from across the cognitive sciences, the book is valuable for philosophers of mind, developmental and comparative psychologists, and neuroscientists.

Michael J. Loux here presents a fresh reading of two of the most important books of the Metaphysics, Books Z and H, in which Aristotle presents his mature ...

This paper focuses on the inheritance of human handedness and cerebral lateralization within the more general context of structural biological asymmetries. The morphogenesis of asymmetrical structures, such as the heart in vertebrates, depends upon a complex interaction between information coded in the cytoplasm and in the genes, but the polarity of asymmetry seems to depend on the cytoplasmic rather than the genetic code. Indeed it is extremely difficult to find clear-cut examples in which thedirectionof an asymmetry is under genetic control. (...) As one possible case, there is some evidence that the direction, clockwise or counterclockwise, of rotation of the abdomen in certain mutant strains ofDrosophilais controlled by a particular gene locus, although there appears to be some degree of confusion on this point. By contrast, it is much easier to find examples in which thedegreebut not the direction of asymmetry is under genetic control. For instance, there is a mutant strain of mice in which half of the animals displaysitus inversusof the viscera. The proportion has remained at one half despite many years of inbreeding, suggesting that the mutant allele effectively cancels the normalsitusand allows the asymmetry to be specified in random fashion.Although this account does not deny that the right hemisphere of humans may be the more specialized for certain functions, it does attribute a leading or dominant role to the left hemisphere (at least in most individuals). We suggest that so-called “right-hemisphere” functions are essentially acquired by default, due to the left hemisphere's prior involvement with speech and skilled motor acts; we note, for instance, that these right-hemisphere functions include rather elementary perceptual processes. But perhaps the more critical prediction from our account is that the phenomenon of equipotentiality should be unidirectional: the right (lagging) hemisphere should be more disposed to take over left-hemisphere functions following early lesions than is the left (leading) hemisphere to take over right-hemisphere functions. We note preliminary evidence that this may be so. (shrink)