Lateral gene transfer, the exchange of genetic information between lineages, not only makes construction of a universal Tree of Life difficult to achieve, but calls into question the utility and meaning of any result. Here I review the science of prokaryotic LGT, the philosophy of the TOL as it figured in Darwin’s formulation of the Theory of Evolution, and the politics of the current debate within the discipline over how threats to the TOL should be represented outside it. We could (...) encourage a more realistic and supportive public understanding of evolution by admitting that what we believe in is not a unified meta-theory but a versatile and well-stocked explanatory toolkit. (shrink)

This paper, like many before it, aims to solve the “species problem” by declaring it a non-problem. It borrows its title from an earlier article by Jeff Lawrence and its philosophical concepts from Marc Ereshefsky, John Dupré, Peter Godfrey-Smith, Ken Waters, and Jody Hey. The emphasis is on bacteria, but my pragmatic species anti-realist conclusion may be a general one.

To date, no definition of life has been unequivocally accepted by the scientific community. In frustration, some authors advocate alternatives to standard definitions. These include using a list of characteristic features, focusing on life’s effects, or categorizing biospheres rather than life itself; treating life as a fuzzy category, a process or a cluster of contingent properties; or advocating a ‘wait-and-see’ approach until other examples of life are created or discovered. But these skeptical, operational, and pluralistic approaches have intensified the debate, (...) rather than settled it. Given the failure of even these approaches, we advocate a new strategy. In this paper, we reverse the usual line of reasoning and argue that the “life problem” arises from thinking incorrectly about the nature of life. Scientists most often conceptualize life as a class or kind, with earthly life as a single instance of it. Instead, we advocate thinking about Earth’s Life as an individual, in the way that species are now thought to be. In this view, Life is a monophyletic clade that originated with a last universal common ancestor, and includes all its descendants. We can continue to use the category ‘life’ pragmatically to refer to similarities between various phenomena and Life. But the relevant similarities are a matter of interest and preference, not a matter of fact. The search for other life in the Universe, then, is merely a search for entities that resemble parts of Life in whatever sense astrobiologists find most appealing. This does not mean that the search for evolved complexity elsewhere in the universe or its creation in the lab are futile endeavors, but that debates over whether they count as ‘life’ are. Ironically, finally abandoning the concept ‘life’ may make our searches for evolved complexity more fruitful. We explain why. (shrink)

This work aims to describe how developments in thinking on evolutionary biology require re-assessment of initial rejection of the relevance and applicability of neo-Darwinian evolution to the Gaia hypothesis.

That holobionts are units of selection squares poorly with the observation that microbes are often recruited from the environment, not passed down vertically from parent to offspring, as required for collective reproduction. The taxonomic makeup of a holobiont’s microbial community may vary over its lifetime and differ from that of conspecifics. In contrast, biochemical functions of the microbiota and contributions to host biology are more conserved, with taxonomically variable but functionally similar microbes recurring across generations and hosts. To save what (...) is of interest in holobiont thinking, we propose casting metabolic and developmental interaction patterns, rather than the taxa responsible for them, as units of selection. Such units need not directly reproduce or form parent-offspring lineages: their prior existence has created the conditions under which taxa with the genes necessary to carry out their steps have evolved in large numbers. These taxa or genes will reconstruct the original interaction patterns when favorable conditions occur. Interaction patterns will vary in ways that affect the likelihood of and circumstances under which such reconstruction occurs. Thus, they vary in fitness, and evolution by natural selection will occur at this level. It is on the persistence, reconstruction, and spread of such interaction patterns that students of holobiosis should concentrate, we suggest. This model also addresses other multi-species collectively beneficial interactions, such as biofilms or biogeochemical cycles maintaining all life. (shrink)

'China, by her resources and her population, is capable of being the greatest power in the world after the United States.' Bertrand Russell, The Problem of China In 1920 the philosopher Bertrand Russell spent a year in China as Professor of Philosophy at the University of Beijing, where his lectures on mathematical logic enthralled students and listeners, including Mao Tse Tung, who attended some of Russell's talks. Written at a time when China was largely regarded by the (...) West as backward and weak, The Problem of China sees Russell rise above the prejudices of his era and presciently assess China's past, present and future. Russell brings his analytical and insightful eye to bear on some fundamental aspects of China's history and politics, cautioning China against adopting a purely Western model of social and economic development, which he regarded as characterized by a combination of greed and militarism. Beginning with an overview of nineteenth-century Chinese history and considering China's relations with Japan and Russia, Russell then contrasts Chinese civilization with Western. He devotes a fascinating chapter to the character of the Chinese, which he argues is complex but ultimately defined by a 'pacific temper'. With uncanny foresight, Russell predicts China's resurgence, but only if it is able to establish an orderly government, promote industrial development under Chinese control and foster the spread of education. This Routledge Classics edition includes a new introduction by Bernard Linsky. (shrink)

Studies on rational conjecture, inference, and reckoning.

Clade selection is unpopular with philosophers who otherwise accept multilevel selection theory. Clades cannot reproduce, and reproduction is widely thought necessary for evolution by natural selection, especially of complex adaptations. Using microbial evolutionary processes as heuristics, I argue contrariwise, that (1) clade growth (proliferation of contained species) substitutes for clade reproduction in the evolution of complex adaptation, (2) clade-level properties favoring persistence – species richness, dispersal, divergence, and possibly intraclade cooperation – are not collapsible into species-level traits, (3) such properties (...) can be maintained by selection on clades, and (4) clade selection extends the explanatory power of the theory of evolution. (shrink)

Here I advance two related evolutionary propositions. (1) Natural selection is most often considered to require competition between reproducing “individuals”, sometimes quite broadly conceived, as in cases of clonal, species or multispecies-community selection. But differential survival of non-competing and non-reproducing individuals will also result in increasing frequencies of survival-promoting “adaptations” among survivors, and thus is also a kind of natural selection. (2) Darwinists have challenged the view that the Earth’s biosphere is an evolved global homeostatic system. Since there is only (...) one biosphere, reproductive competition cannot have been involved in selection for such survival-promoting adaptations, they claim. But natural selection through survival could reconcile Gaia with evolutionary theory. (shrink)

Our understanding of what microbes are and how they evolve has undergone many radical shifts since the late nineteenth century, when many still believed that bacteria could be spontaneously generated and most thought microbial “species” (if any) to be unstable and interchangeable in form and function (pleomorphic). By the late twentieth century, an ontology based on single cells and definable species with predictable properties, evolving like species of animals or plants, was widely accepted. Now, however, genomic and metagenomic data show (...) that lateral gene transfer compromises this picture of stability and predictability, and refocuses our attention on multilineage communities. Treating such communities as unstable but identifiable evolving “individuals” makes us again pleomorphists, of a sort. (shrink)

Bernard Williams identifies Hume as “in some ways an archetypal reconciler” who, nevertheless, displays “a striking resistance to some of the central tenets of what [Williams calls] ‘morality’”. This assessment, it is argued, is generally correct. There are, however, some significant points of difference in their views concerning moral responsibility. This includes Williams’s view that a naturalistic project of the kind that Hume pursues is of limited value when it comes to making sense of “morality’s” illusions about responsibility and blame. (...) It is, Williams maintains, only when we consider moral responsibility in genealogical terms, which gives attention to the importance of culture and history, that we can find a way of exposing the various prejudices and illusions of “the morality system”. Nevertheless, despite these differences, what Hume and Williams share is a fundamental commitment to provide a more “truthful” and “realistic” understanding of moral responsibility and our human ethical predicament. (shrink)

The origin and prevalence of transposable elements may best be understood as resulting from “selfish” evolutionary processes at the within-genome level, with relevant populations being all members of the same TE family or all potentially mobile DNAs in a species. But the maintenance of families of TEs as evolutionary drivers, if taken as a consequence of selection, might be better understood as a consequence of selection at the level of species or higher, with the relevant populations being species or ecosystems (...) varying in their possession of TEs. In 2015, Brunet and Doolittle made the case for legitimizing claims for an evolutionary role for TEs by recasting such claims as being about species selection. Here I further develop this “how possibly” argument. I note that with a forgivingly broad construal of evolution by natural selection we might come to appreciate many aspects of Life on earth as its products, and TEs as—possibly—contributors to the success of Life by selection at several levels of a biological hierarchy. Thinking broadly makes this proposition a testable Darwinian one. (shrink)

Eukaryogenesis is widely viewed as an improbable evolutionary transition uniquely affecting the evolution of life on this planet. However, scientific and popular rhetoric extolling this event as a singularity lacks rigorous evidential and statistical support. Here, we question several of the usual claims about the specialness of eukaryogenesis, focusing on both eukaryogenesis as a process and its outcome, the eukaryotic cell. We argue in favor of four ideas. First, the criteria by which we judge eukaryogenesis to have required a genuinely (...) unlikely series of events 2 billion years in the making are being eroded by discoveries that fill in the gaps of the prokaryote:eukaryote “discontinuity.” Second, eukaryogenesis confronts evolutionary theory in ways not different from other evolutionary transitions in individuality; parallel systems can be found at several hierarchical levels. Third, identifying which of several complex cellular features confer on eukaryotes a putative richer evolutionary potential remains an area of speculation: various keys to success have been proposed and rejected over the five-decade history of research in this area. Fourth, and perhaps most importantly, it is difficult and may be impossible to eliminate eukaryocentric bias from the measures by which eukaryotes as a whole are judged to have achieved greater success than prokaryotes as a whole. Overall, we question whether premises of existing theories about the uniqueness of eukaryogenesis and the greater evolutionary potential of eukaryotes have been objectively formulated and whether, despite widespread acceptance that eukaryogenesis was “special,” any such notion has more than rhetorical value. (shrink)

Constructive Neutral Evolution is an evolutionary mechanism that can explain much molecular inter-dependence and organismal complexity without assuming positive selection favoring such dependency or complexity, either directly or as a byproduct of adaptation. It differs from but complements other non-selective explanations for complexity, such as genetic drift and the Zero Force Evolutionary Law, by being ratchet-like in character. With CNE, purifying selection maintains dependencies or complexities that were neutrally evolved. Preliminary treatments use it to explain specific genetic and molecular structures (...) or processes, such as retained gene duplications, the spliceosome, and RNA editing. Here we aim to expand the scope of such explanation beyond the molecular level, integrating CNE with Multi-Level Selection theory, and arguing that several popular higher-level selection scenarios are in fact instances of CNE. Suitably contextualized, CNE occurs at any level in the biological hierarchy at which natural selection as normally construed occurs. As examples, we focus on modularity in protein–protein interaction networks or “interactomes,” the origin of eukaryotic cells and the evolution of co-dependence in microbial communities—a variant of the “Black Queen Hypothesis” which we call the “Gray Queen Hypothesis”. (shrink)

Iris Murdoch offers a distinctive conception of moral psychology. She suggests that to develop a moral psychology is to develop what she calls a soul-picture; different philosophical moral psychologies are, as she puts it, “rival soul-pictures.” In this paper I clarify Murdoch’s generic notion of “soul-picture,” the genus of which, for example, Aristotle’s, Kant’s, Nietzsche’s, and Murdoch’s constitute rival species. Are all philosophical moral psychologies soul-pictures? If not, what are the criteria that a moral psychology must meet in order to (...) qualify as a soul-picture? I propose five key dimensions. A soul-picture provides a picture of the soul or self that is 1) holistic, 2) value-rich and psychologically realistic (for Murdoch these are intertwined), 3) reflexive, 4) therapeutic and 5) the articulation of which makes use of imaginative language. (shrink)

The Scottish philosopher David Hume (1711-1776) is widely regarded as the greatest and most significant English-speaking philosopher and often seen as having had the most influence on the way philosophy is practiced today in the West. His reputation is based not only on the quality of his philosophical thought but also on the breadth and scope of his writings, which ranged over metaphysics, epistemology, morals, politics, religion, and aesthetics. The Handbook's 38 newly commissioned chapters are divided into six parts: Central (...) Themes; Metaphysics and Epistemology; Passion, Morality and Politics; Aesthetics, History, and Economics; Religion; Hume and the Enlightenment; and After Hume. The volume also features an introduction from editor Paul Russell and a chapter on Hume's biography. (shrink)

Bertrand Russell was one of the greatest logicians since Aristotle, and one of the most important philosophers of the past two hundred years. As we approach the 125th anniversary of the Nobel laureate's birth, his works continue to spark debate, resounding with unmatched timeliness and power. The Problems of Philosophy, one of the most popular works in Russell's prolific collection of writings, has become core reading in philosophy. Clear and accessible, this little book is an intelligible and stimulating (...) guide to those problems of philosophy which often mistakenly lead to its status as too lofty and abstruse for the lay mind. Focusing on problems he believes will provoke positive and constructive discussion, Russell concentrates on knowledge rather than metaphysics, steering the reader through his famous 1910 distinction between "knowledge by acquaintance and knowledge by description," and introducing important theories of Descartes, Kant, Hegel, Hume, Locke, Plato, and others to lay the foundation for philosophical inquiry by general readers and scholars alike.With a new introduction by John Perry, this valuable work is a perfect introduction to the field and will continue to stimulate philosophical discussion as it has done for nearly forty years. (shrink)

Biological science uses multiple species concepts. Order can be brought to this diversity if we recognize two key features. First, any given species concept is likely to have a patchwork structure, generated by repeated application of the concept to new domains. We illustrate this by showing how two species concepts (biological and ecological) have been modified from their initial eukaryotic applications to apply to prokaryotes. Second, both within and between patches, distinct species concepts may interact and hybridize. We thus defend (...) a semantic picture of the species concept as a collection of interacting patchwork structures. Thus, although not all uses of the term pick out the same kind of unit in nature, the diversity of uses reflects something more than mere polysemy. We suggest that the emphasis on the use of species to pick out natural units is itself problematic, because that is not the term’s sole function. In particular, species concepts are used to manage inquiry into processes of speciation, even when these processes do not produce clearly delimited species. (shrink)

In fact, nearly every scientist who has written on the general subject of evolution has felt compelled to show how deftly he can skate toward the abyss of teleology without falling in.J.H. Campbell, 163Molecular biology has as its primary objective the elucidation of the coupling between genotype and phenotype. This goal has so far been pursued within a neoDarwinian theoretical framework which is relatively limited. Within this framework we can indeed understand remarkably well the mechanisms of replication and expression of (...) genes and the means by which replication and expression are regulated in cells; we know how genotype determines phenotype at the molecular level, in single cells. We are also close to an understanding of the relationship between genes and development in muticellular animals and plants. (shrink)

The art of rational conjecture.--The art of drawing inferences.--The art of reckoning.

In fact, nearly every scientist who has written on the general subject of evolution has felt compelled to show how deftly he can skate toward the abyss of teleology without falling in.J.H. Campbell, 163Molecular biology has as its primary objective the elucidation of the coupling between genotype and phenotype. This goal has so far been pursued within a neoDarwinian theoretical framework which is relatively limited. Within this framework we can indeed understand remarkably well the mechanisms of replication and expression of (...) genes and the means by which replication and expression are regulated in cells; we know how genotype determines phenotype at the molecular level, in single cells. We are also close to an understanding of the relationship between genes and development in muticellular animals and plants. (shrink)

Bertrand Russell is concerned in this book with the foundations of knowledge. He approaches his subject through a discussion of language, the relationships of truth to experience and an investigation into how knowledge of the structure of language helps our understanding of the structure of the world. This edition includes a new introduction by Thomas Baldwin, Clare College, Cambridge.

The Problems of Philosophy is a 1912 book by Bertrand Russell, in which Russell attempts to create a brief and accessible guide to the problems of philosophy. Focusing on problems he believes will provoke positive and constructive discussion, Russell concentrates on knowledge rather than metaphysics: If it is uncertain that external objects exist, how can we then have knowledge of them but by probability. There is no reason to doubt the existence of external objects simply because of (...) sense data. Russell guides the reader through his famous 1910 distinction between knowledge by acquaintance and knowledge by description and introduces important theories of Plato, Aristotle, René Descartes, David Hume, John Locke, Immanuel Kant, Georg Wilhelm Friedrich Hegel and others to lay the foundation for philosophical inquiry by general readers and scholars alike. "In the following pages I have confined myself in the main to those problems of philosophy in regard to which I thought it possible to say something positive and constructive, since merely negative criticism seemed out of place. For this reason, theory of knowledge occupies a larger space than metaphysics in the present volume, and some topics much discussed by philosophers are treated very briefly, if at all. (shrink)

This anthology is a thorough introduction to classic literature for those who have not yet experienced these literary masterworks. For those who have known and loved these works in the past, this is an invitation to reunite with old friends in a fresh new format. From Shakespeare's finesse to Oscar Wilde's wit, this unique collection brings together works as diverse and influential as The Pilgrim's Progress and Othello. As an anthology that invites readers to immerse themselves in the masterpieces of (...) the literary giants, it is must-have addition to any library. (shrink)

This brilliant and controversial work investigates the relationship between 'individual' and 'scientific' knowledge.

An unabridged edition with updated footnotes and layout, to include: Recent Criticisms of "Consciousness" - Instinct and Habit - Desire and Feeling - Influence of Past History on Present Occurrences in Living Organisms - Psychological and Physical Causal Laws - Introspection - The Definition of Perception - Sensations and Images - Memory - Words and Meaning - General Ideas and Thought - Belief - Truth and Falsehood - Emotions and Will - Characteristics of Mental Phenomena.

Academic literature addressing the topic of business ethics has paid little attention to cross-cultural studies of business ethics. Uncertainty exists concerning the effect of culture on ethical beliefs. The purpose of this research is to compare the ethical beliefs of managers operating in South Africa and Australia. Responses of 52 managers to a series of ethical scenarios were sought. Results indicate that despite differences in socio-cultural and political factors there are no statistically significant differences between the two groups regarding their (...) own ethical beliefs. Results thus support the view that culture has little or no impact on ethical beliefs. (shrink)

On a remarkably thin base of evidence – largely the spectral analysis of points of light – astronomers possess, or appear to possess, an abundance of knowledge about the structure and history of the universe. We likewise know more than might even have been imagined a few centuries ago about the nature of physical matter, about the mechanisms of life, about the ancient past. Enormous theoretical and methodological ingenuity has been required to obtain such knowledge; it does not invite easy (...) discovery by the untutored. It may seem odd, then, that we have so little scientific knowledge of what lies closest at hand, apparently ripe for easy discovery, and of greatest importance for our quality of life: our own conscious experience – our sensory experiences and pains, for example, our inner speech and imagery, our felt emotion. Scientists know quite a bit about human visual capacities and the brain processes involved in vision, much less about the subjective experience of seeing; a fair bit about the physiology of emotion, almost nothing about its phenomenology. Philosophers began in earnest in the seventeenth and eighteenth centuries to describe and classify our patterns of conscious experience. John Locke, for instance, divided experienced “ideas” into those that arise from sensation and those that arise from reflection, and he began to classify them into. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Deceit, Desire, and The Dunciad:Mimetic Theory and Alexander PopeAllan Doolittle (bio)Anxiety expressed over what is often termed "information overload"1 is by no means solely a phenomenon of our electronic age. Recent scholarship has traced this concern as far back as the early modern period. The increased production and dissemination of books in the sixteenth and seventeenth centuries was a source of "wonder and anxiety"2 for authors and prompted (...) the need for a "substantial reorganization of the intellectual world."3 Seventeenth-century French scholar and critic Adrien Baillet gave warning of an impending barbarism unless there was a "separating [of] those books which we must throw out or leave in oblivion from those which one should save."4 The most recognizable expression of this imperative to sort the printed wheat from the chaff comes from the voices of some of eighteenth-century England's most studied, most admired, yet also detested authors, the Scriblerians. From this celebrated literary group came "the three great Tory satires, Jonathan Swift's Gulliver's Travels, John Gay's Fables and Alexander Pope's The Dunciad."5Christian Thorne, in his discussion of these works in relation to the rise of the public sphere in early modern England, defines the Scriblerian rallying cry as a protest against "the rise of print culture... in which signification will [End Page 1] run amok, flooding the polity with an undifferentiated mass of contradictory opinions and arguments and thus corroding traditional forms of citizenship or civic virtue."6 Pope saw the deluge of aspiring authors and their printed output as a destructive force, a force that had a leveling effect on what he perceived as the traditional structure of the cultural hierarchy. In this article, I will look specifically at the career of Alexander Pope and his lifelong struggle against all but a small number of those who populated what Samuel Johnson called the "Age of Authors."Pope's career is indelibly marked with conflict. This conflict stemmed from Pope's untiring efforts to regulate the field in which he worked, to promote himself and his friends, and to do everything at his disposal to thwart the efforts of those whom he saw as threatening his literary endeavors. His adversaries, most often the professional ranks of Grub Street writers and publishers, served as fodder for Pope's satire and were deeply entwined in Pope's literary output. However, the adversaries he most wanted to be rid of—the primary target of his purposeful and brilliant satire—were not the "hackney scribblers" typical of Grub Street but those most threatening to Pope's professional writing career: "verbal critics" or literary scholars.7 The threat came in the form of the newly emerging critical techniques of philological scholarship. It is my contention that the literary scholars possessed knowledge that Pope showed himself to be desirous of, but that he was incapable of attaining.In this paper I will apply René Girard's mimetic theory both to Pope's relationships with these scholars and to his depiction of them in The Dunciad. The application of Girard's theory helps to explain Pope's motivation in writing, expanding, and obsessing over a poem that was seemingly more trouble than it was worth. The publication history of the poem, which is "exceedingly complicated,"8 "cost [Pope] as much pains as anything [he] ever wrote"9 and brought down an avalanche of ridicule and abuse on him, prompting many to wonder "what can possibly have impelled him to do what he did?"10 This article will go some distance toward answering this question and will also provide insight into the way The Dunciad operated in the service of Pope's attempt to shape the literary culture of early-eighteenth-century England. I will do what no critic to date has yet attempted: I will use Girard's theory to clarify the relationship between Pope's work with the classics and that of his rival classical scholars, and to show how these two threads are woven into his magnum opus, The Dunciad.René Girard's insightful and controversial theory of the nature and origin of human culture may be grouped into three... (shrink)

Birdsong is widely analysed and discussed by people coming from both musical and scientific backgrounds. Both approaches provide valuable insight, but I argue that it is only through combining musical and scientific points of view, as well as perspectives from more tangentially related fields, that we can obtain the best possible understanding of birdsong. In this paper, I discuss how my own training as a musician, and in particular as a composer, affects how I listen to and parse birdsong. I (...) identify nine areas of overlap between human music and birdsong, which may serve as starting points both for musical and scientific analysis, as well as for interdisciplinary analysis as practiced in the developing field of “zoomusicology.” Using the hermit thrush (Catharus guttatus) as an example, I discuss how the song of a single species has been described by writers from a variety of disciplines, including music, literature, and the sciences, as well as how we can contextualise these varied perspectives in terms of broader cultural thought trends. I end with discussion of how combining approaches from multiple fields can help us to figure out new questions to ask, can help us identify how our own cultural biases may affect how we hear birdsong, and ultimately can help us develop richer and more nuanced understandings of the songs themselves. (shrink)

Native food production in the Eastern Woodlands of North America before, and at the time of, European contact has been described by several writers as “slash-and-burn agriculture,” “shifting cultivation,” and even “swidden.” Select quotes from various early explorers, such as John Smith of Pocahontas fame, have been used out of context to support this position. Solid archaeological evidence of such practices is next to non-existent, as are ethnographic parallels from the region. In reality, the best data are documentary. Unlike previous (...) assessments, this paper evaluates sixteenth and seventeenth century ethnohistorical references to anything that can be even remotely construed as supportive of previous claims. Analyzed as a group these sources reveal something completely different from what common knowledge would have us believe. References to the slashing, the burning, and the shifting of fields are reasonably abundant. Rarely, however, are all three activities mentioned in a single passage, or by one chronicler. Furthermore, subtleties often overlooked in these quotes reveal great insight into native practices. This paper assesses explorers' and early settlers' descriptions in the context of the larger body of literature dealing with the ecology of swidden agriculture today. Indigenous fields in the Eastern Woodlands tended to be large, numerous, contiguous, and cleared of roots and stumps. Fields previously cleared of trees were covered with grass prior to preparation for planting. They were permanently cultivated. This condition stands in marked contrast to present-day swidden fields in other parts of the world that tend to be small, few, scattered, partially cleared of trees, and cultivated for only a year or two before being abandoned. Slash-and-burn shifting cultivation became common only after European settlers introduced steel axes. It was then practiced on uplands, not the formerly cultivated floodplains that were usurped by interlopers. (shrink)

The genome contains elements which are most easily understood as the products of selection operating at the level of the genome, without regard to phenotypic effect. The properties of such elements, and more general implications of molecular biological data, are discussed.

Understanding community-level selection using Lewontin’s criteria requires both community-level inheritance and community-level heritability, and in the discipline of community and ecosystem genetics, these are often conflated. While there are existing studies that show the possibility of both, these studies impose community-level inheritance as a product of the experimental design. For this reason, these experiments provide only weak support for the existence of community-level selection in nature. By contrast, treating communities as interactors (in line with Hull’s replicator-interactor framework or Dawkins’s idea (...) of the “extended phenotype”) provides a more plausible and empirically supportable model for the role of ecological communities in the evolutionary process. (shrink)

The first complete sequence of an archaebacterial genome, that of Methanococcus jannaschii, has recently been published(1). Less than half of the open reading frames (ORFs) can be assigned a function based on similarity to known sequences in databases. These assignable ORFs fall into two general classes; those involved in transcription, translation and replication are more similar to eukaryotic homologs, while those determining metabolic processes are more similar to eubacterial versions. The immense but very rewarding task of making biological and evolutionary (...) sense of all this information has only just begun. (shrink)

Here we endorse Hull’s replicator/interactor framework as providing the overarching understanding sought by MacCord and Maienschein. We suggest that difficulties in seeing the regeneration of limbs by salamanders and of forest ecosystems after fires as similar evolutionary processes can be overcome in this framework. In generalizing Dawkins’s “selfish gene” perspective, Hull defined natural selection as “a process in which the differential extinction and proliferation of interactors causes the differential perpetuation of the replicators that produced them”. Although genes and bacteria are (...) simultaneously both replicators and interactors, communities and ecosystems are generally only interactors. As reproducers, members of sexual species are intermediate. Within such species, organisms are indeed the interactors whose “differential extinction and proliferation” causes the “differential perpetuation” of replicators. But sexually-reproducing organisms do not individually replicate, persist, or recur as interactors, and in consequence it is only those genes causing an interactor differential that are specifically perpetuated in the long run. Higher-level interactors may seldom if ever reproduce, but their recurrence does enable the “differential perpetuation” of replicators specifically responsible for their “differential extinction and proliferation”. In offering answers to the question “What are the replicators specifically responsible for the differential extinction and proliferation of such higher-level entities?” we hope to unify adaptive regeneration across scales, from organisms to ecosystems. (shrink)

Diverse living systems possess the capacity for regeneration; that is, they can under some circumstances repair, re-produce, and maintain themselves in the face of disturbance or damage. Think of systems as diverse as forests, microbial biofilms, corals, salamanders, hydra, and human skin cells. This capacity is fundamental to life—without it, many biological systems would be too fragile to cope with stress and would frequently collapse—but because it is multiply realized in wildly different living systems at many scales, finding a common (...) understanding may seem futile, and in fact research has proceeded along independent lines. For example, the sciences of organismal regeneration and ecological regeneration appear to have little more than a nominal relationship. Progress towards unification can be made, we think, by turning to evolutionary theory, specifically by synthesizing recent discussions of the evolution of individuals versus collectives with older literature about replicators versus interactors. This allows us to provide a partial answer in response to MacCord and Maienschein’s call for “basic units and mechanisms” of regeneration, relevant when that process is “adaptive.” We argue that the basics of adaptive regeneration can be understood and generalized through a modification of David Hull’s replicator-interactor framework. (shrink)

This editorial introduces a series of review articles concerning the ways in which recent work on microbial evolution has both deepened and challenged the modern synthesis. The authors develop a framework for thinking about theory change in biology.

Focus on the evolutionary origins of musicality has been neglected relative to attention on language, so these new proposals are welcome stimulants. We argue for a broad comparative approach to understanding how the elements of musicality evolved, and against the use of overly simplistic evolutionary accounts.