Jean Gayon’s encounters with American evolutionary biologists and philosophers of biology affected his project of justifying the Darwinian research tradition. He challenged entrenched views about evolution in France by showing how the population-genetic theory of natural selectionSelection removed conceptual blockages that had thwarted the Darwinian research tradition. He taught his American colleagues how important French physiological genetics was to the DarwinismDarwinism of the modern evolutionary synthesis and, with Richard BurianBurian, Richard, stressed the compatibility of the (...) class='Hi'>Synthesis with postwar French molecular geneticsMolecular genetics. His seamless integration of history and philosophy of biology helped create an international learned society in which historians and philosophers of biology work together (ISSHSPB). (shrink)

Using the evolution of the stickleback family of subarctic fish as a touchstone, we explore the effect of new discoveries about regulatory genetics, developmental plasticity, and epigenetic inheritance on the conceptual foundations of the Modern Evolutionary Synthesis. Identifying the creativity of natural selection as the hallmark of the Modern Synthesis, we show that since its inception its adherents have pursued a variety of research projects that at first seemed to conflict with its principles, but were (...) accommodated. We situate challenges coming from developmental biology in a dialectic between innovation and tradition, suggesting on the basis of past episodes that even if developmental plasticity and epigenetic inheritance are aligned with its principles the Modern Synthesis will be significantly affected. (shrink)

In 2011, Peterson suggested that the main reason why C.H. Waddington was essentially ignored by the framers of the modern evolutionary synthesis in the 1950s was because they were Cartesian reductionists and mathematical population geneticists while he was a Whiteheadian organicist and experimental geneticist who worked with Drosophila. This paper suggests a further reason that can only be seen now. The former defined genes and their alleles by their selectable phenotypes, essentially the Mendelian view, while Waddington defined (...) a gene through its functional role as determined by genetic analysis, a view that foresaw the modern view that a gene is a DNA sequence with some function. The former were interested in selection, while Waddington focused on variation. The differences between the two views of a gene are briefly considered in the context of systems biology. (shrink)

Welch :263–279, 2017) has recently proposed two possible explanations for why the field of evolutionary biology is plagued by a steady stream of claims that it needs urgent reform. It is either seriously deficient and incapable of incorporating ideas that are new, relevant and plausible or it is not seriously deficient at all but is prone to attracting discontent and to the championing of ideas that are not very relevant, plausible and/or not really new. He argues for the second (...) explanation. This paper presents a twofold critique of his analysis: firstly, the main calls for reform do not concern the field of evolutionary biology in general but rather, or more specifically, the modern evolutionary synthesis. Secondly, and most importantly, these calls are not only inspired by the factors, enumerated by Welch, but are also, and even primarily, motivated by four problematic characteristics of the modern synthesis. This point is illustrated through a short analysis of the latest reform challenge to the modern synthesis, the so-called extended evolutionary synthesis. We conclude with the suggestion that the modern synthesis should be amended, rather than replaced. (shrink)

Recent debates between proponents of the modern evolutionary synthesis (the standard model in evolutionary biology) and those of a possible extended synthesis are a good example of the fascinating tangle among empirical, theoretical, and conceptual or philosophical matters that is the practice of evolutionary biology. In this essay, we briefly discuss two case studies from this debate, highlighting the relevance of philosophical thinking to evolutionary biologists in the hope of spurring further constructive cross-pollination (...) between the two fields. (shrink)

The Extended Evolutionary Synthesis (EES) debate is gaining ground in contemporary evolutionary biology. In parallel, a number of philosophical standpoints have emerged in an attempt to clarify what exactly is represented by the EES. For Massimo Pigliucci, we are in the wake of the newest instantiation of a persisting Kuhnian paradigm; in contrast, Telmo Pievani has contended that the transition to an EES could be best represented as a progressive reformation of a prior Lakatosian scientific research program, (...) with the extension of its Neo-Darwinian core and the addition of a brand-new protective belt of assumptions and auxiliary hypotheses. Here, we argue that those philosophical vantage points are not the only ways to interpret what current proposals to ‘extend’ the Modern Synthesis-derived ‘standard evolutionary theory’ (SET) entail in terms of theoretical change in evolutionary biology. We specifically propose the image of the emergent EES as a vast network of models and interweaved representations that, instantiated in diverse practices, are connected and related in multiple ways. Under that assumption, the EES could be articulated around a paraconsistent network of evolutionary theories (including some elements of the SET), as well as models, practices and representation systems of contemporary evolutionary biology, with edges and nodes that change their position and centrality as a consequence of the co-construction and stabilization of facts and historical discussions revolving around the epistemic goals of this area of the life sciences. We then critically examine the purported structure of the EES—published by Laland and collaborators in 2015—in light of our own network-based proposal. Finally, we consider which epistemic units of Evo-Devo are present or still missing from the EES, in preparation for further analyses of the topic of explanatory integration in this conceptual framework. (shrink)

The Modern Synthesis (MS) is the current paradigm in evolutionary biology. It was actually built by expanding on the conceptual foundations laid out by its predecessors, Darwinism and neo-Darwinism. For sometime now there has been talk of a new Extended Evolutionary Synthesis (EES), and this article begins to outline why we may need such an extension, and how it may come about. As philosopher Karl Popper has noticed, the current evolutionary theory is a theory (...) of genes, and we still lack a theory of forms. The field began, in fact, as a theory of forms in Darwin’s days, and the major goal that an EES will aim for is a unification of our theories of genes and of forms. This may be achieved through an organic grafting of novel concepts onto the foundational structure of the MS, particularly evolvability, phenotypic plasticity, epigenetic inheritance, complexity theory, and the theory of evolution in highly dimensional adaptive landscapes. (shrink)

To approach the issue of the recent proposal of an Extended Evolutionary Synthesis (EES) put forth by Massimo Pigliucci and Gerd Müller, I suggest to consider the EES as a metascientific view: a description of what’s new in how evolutionary biology is carried out, not only a description of recently learned aspects of evolution. Knowing ‘what is it to do research’ in evolutionary biology, today versus yesterday, can aid training, research and career choices, establishment of relationships (...) and collaborations, decision of funding and research policies, in order to make the field advance for the better. After reviewing the concepts associated to the EES proposal (categorized for convenience as mechanisms, measures, fields, perspectives and applications), I show their transience, and sketch out ongoing disagreements about the EES. Then I examine the deep difficulties, i.e., the enormity and complexity of the covered field, affecting the achievement of trusted metascientific views; the insufficiency of conceptual analysis to capture the substance of scientific research; the entanglement between empirical and metascientific concepts, between multiple chronologies, and between descriptive and normative intentions; and the ineliminable stakeholding of any reviewer involved in the reviewed field. I propose that disciplines such as scientometrics, ethnography, sociology, economics and history, combined with conceptual analysis, inspire a more rigorous approach to the evolutionary biology scientific community, more grounded and shared, confirming or transforming claims for ‘synthesis’ while preserving their maintenance goals. (shrink)

In this paper I propose a new interpretation of the British evolutionary synthesis. The synthetic work of J. B. S. Haldane, R. A. Fisher and J. S. Huxley was characterized by both an integration of Mendelism and Darwinism and the unification of different biological subdisciplines within a coherent framework. But it must also be seen as a bold and synthetic Darwinian program in which the biosciences served as a utopian blueprint for the progress of civilization. Describing the futuristic (...) visions of these three scientists in their synthetic heydays, I show that, despite a number of important divergences, their biopolitical ideals could be biased toward a controlled and regimented utopian society. Their common ideals entailed a social order where liberal and democratic principles were partially or totally suspended in favor of bioscientific control and planning for the future. Finally, I will argue that the original redefinition of Darwinism that modern synthesizers proposed is a significant historical example of how Darwinism has been used and adapted in different contexts. The lesson I draw from this account is a venerable one: that, whenever we wish to define Darwinism, we need to recognize not only its scientific content and achievements but expose the other traditions and ideologies it may have supported. (shrink)

Contemporary evolutionary biology comprises a plural landscape of multiple co-existent conceptual frameworks and strenuous voices that disagree on the nature and scope of evolutionary theory. Since the mid-eighties, some of these conceptual frameworks have denounced the ontologies of the Modern Synthesis and of the updated Standard Theory of Evolution as unfinished or even flawed. In this paper, we analyze and compare two of those conceptual frameworks, namely Niles Eldredge’s Hierarchy Theory of Evolution (with its extended ontology (...) of evolutionary entities) and the Extended Evolutionary Synthesis (with its proposal of an extended ontology of evolutionary processes), in an attempt to map some epistemic bridges (e.g. compatible views of causation; niche construction) and some conceptual rifts (e.g. extra-genetic inheritance; different perspectives on macroevolution; contrasting standpoints held in the “externalism–internalism” debate) that exist between them. This paper seeks to encourage theoretical, philosophical and historiographical discussions about pluralism or the possible unification of contemporary evolutionary biology. (shrink)

One central tenet of the Modern Evolutionary Synthesis , and the consensus view among biologists until now, is that all genetic mutations occur by “chance” or at “random” with respect to adaptation. However, the discovery of some molecular mechanisms enhancing mutation rate in response to environmental conditions has given rise to discussions among biologists, historians and philosophers of biology about the “chance” vs “directed” character of mutations . In fact, some argue that mutations due to a particular (...) kind of mutator mechanisms challenge the Modern Synthesis because they are produced when and where needed by the organisms concerned. This paper provides a defense of the Modern Synthesis’ consensus view about the chance nature of all genetic mutations by reacting to Jablonka and Lamb’s analysis of genetic mutations and the explicit Lamarckian flavor of their arguments. I argue that biologists can continue to talk about chance mutations according to what I call and define as the notion of “evolutionary chance,” which I claim is the Modern Synthesis’ consensus view and a reformulation of Darwin’s most influential idea of “chance” variation. Advances in molecular genetics are therefore significant but not revolutionary with respect to the Modern Synthesis’ paradigm. (shrink)

According to a classical narrative, early geneticists, failing to see how Mendelism provides the missing pieces of Darwin’s theory, rejected gradual changes and advocated an implausible yet briefly popular view of evolution-by-mutation; after decades of delay (in which synthesis was prevented by personal conflicts, disciplinary rivalries, and anti-Darwinian animus), Darwinism emerged on a new Mendelian basis. Based on the works of four influential early geneticists – Bateson, de Vries, Morgan and Punnett –, and drawing on recent scholarship, we offer (...) an alternative that turns the classical view on its head. For early geneticists, embracing discrete inheritance and the mutation theory (for the origin of hereditary variation) did not entail rejection of selection, but rejection of Darwin’s non-Mendelian views of heredity and variation, his doctrine of natura non facit saltum, and his conception of “natural selection” as a creative force that shapes features out of masses of infinitesimal differences. We find no evidence of a delay in synthesizing mutation, rules of discrete inheritance, and selection in a Mendelian-Mutationist Synthesis. Instead, before 1918, early geneticists had conceptualized allelic selection, the Hardy–Weinberg equilibrium, the evolution of a quantitative trait under selection, the probability of fixation of a new mutation, and other key innovations. Contemporary evolutionary thinking seems closer to their more ecumenical view than to the restrictive mid-twentieth-century consensus known as the Modern Synthesis. (shrink)

What role does non-genetic inheritance play in evolution? In recent work we have independently and collectively argued that the existence and scope of non-genetic inheritance systems, including epigenetic inheritance, niche construction/ecological inheritance, and cultural inheritance—alongside certain other theory revisions—necessitates an extension to the neo-Darwinian Modern Synthesis (MS) in the form of an Extended Evolutionary Synthesis (EES). However, this argument has been challenged on the grounds that non-genetic inheritance systems are exclusively proximate mechanisms that serve the ultimate (...) function of calibrating organisms to stochastic environments. In this paper we defend our claims, pointing out that critics of the EES (1) conflate non-genetic inheritance with early 20th-century notions of soft inheritance; (2) misunderstand the nature of the EES in relation to the MS; (3) confuse individual phenotypic plasticity with trans-generational non-genetic inheritance; (4) fail to address the extensive theoretical and empirical literature which shows that non-genetic inheritance can generate novel targets for selection, create new genetic equilibria that would not exist in the absence of non-genetic inheritance, and generate phenotypic variation that is independent of genetic variation; (5) artificially limit ultimate explanations for traits to gene-based selection, which is unsatisfactory for phenotypic traits that originate and spread via non-genetic inheritance systems; and (6) fail to provide an explanation for biological organization. We conclude by noting ways in which we feel that an overly gene-centric theory of evolution is hindering progress in biology and other sciences. (shrink)

In this paper, we analyze the debate between the Modern Synthesis and the Extended Evolutionary Synthesis in light of the concept of incommensurability developed by Thomas Kuhn. In order to do so, first we briefly present both the Modern Synthesis and the Extended Evolutionary Synthesis. Then, we clarify the meaning and interpretations of incommensurability throughout Kuhn’s works, concluding that the version of this concept deployed in The Structure of Scientific Revolutions is the (...) best suited to the analysis of scientific disputes. After discussing incommensurability in Kuhn’s works, we address the question of whether the Modern Synthesis and the Extended Evolutionary Synthesis can be considered semantically, methodologically, and ontologically incommensurable, concluding that they can. Finally, we discuss three problems that arise from such a conclusion: firstly, what are the consequences of incommensurability; secondly, which mode of scientific change better explains this current dispute in evolutionary biology; and thirdly, whether rational theory comparison is possible given incommensurability. We suggest that the main consequence of incommensurability is profound disagreement, that the kind of scientific change that better explains the current dispute between the MS and the EES may be scientific specialization, and that incommensurability does not preclude rational theory comparison. (shrink)

The Modern Synthesis (MS) gene-centered population model of evolution is currently being challenged by the Extended Evolutionary Synthesis (ESS) organism-centered developmental model of evolution. The predictions of the EES are here examined with respect to the arguments of Edward Drinker Cope (1840–1897) for an organism-centered evolutionary process in which organisms both shape and are shaped by their environments such that the activities of the organisms themselves play a role in their own evolution.

Evolutionary epistemology has experienced a continuous rise over the last decades. Important new theoretical considerations and novel empirical findings have been integrated into the existing framework. In this paper, I would like to suggest three lines of research that I believe will significantly contribute to further advance EE: ontogenetic considerations, key ideas from cognitive biology, and the framework of the Extended Evolutionary Synthesis. EE, in particular the program of the evolution of epistemological mechanisms, seeks to provide a (...) phylogenetic account of the generation of cognitive processes underlying knowledge creation. Traditionally, EE and EEM have been oriented towards an account of evolutionary theory that mainly drew from the tenets of the Modern Synthesis. The Modern Synthesis largely dismisses ontogenetic processes and considers them irrelevant for evolutionary explanations. If anything, the role of development in evolution is believed to be that of a constraint. There is, however, ample evidence for a tight intertwinement of developmental and evolutionary processes. Organisms employ their cognitive apparatus to interact with the environment in order to achieve a fully functioning perceptual and cognitive nervous system. Also, ontogeny provides generative potentials to enable variations that natural selection can act upon. EEM’s agenda may, therefore, strongly benefit from bringing together ontogenetic and phylogenetic approaches. To grapple with this challenge, an alternative vision of the evolutionary theory termed Extended Evolutionary Synthesis could be used. This extended evolutionary theory explores relationships between the processes of individual development and phenotypic change during evolution and can provide a more suitable framework for EEM to draw from. In recent years, cognitive biology has gained momentum as an independent research field. Cognitive biology builds on the concepts of EEM and understands knowledge as a biogenic phenomenon. Its main objective is also the formulation of substantiated interrelations between cognition and evolution but it focuses on cognitive functionality at all levels of biological organization. It thus employs a “vertical” approach that encompasses nested hierarchies which span from single molecules, cells, and tissues to the organismal level, communities, and societies. In contrast to cognitive biology, EEM is here understood to adopt a “horizontal” approach that focuses on phylogenetic explanations of cognition and knowledge acquisition. Linking EEM with the key ideas of cognitive biology could make EEM’s research program stronger as it can more easily accommodate phylogenetic and ontogenetic questions within a hierarchical, multilevel perspective. This is of particular importance for a more comprehensive account of cognition since living systems are subject to context-dependent causal influences from different organizational levels. In addition to EEM, there is a second program of EE. This program has been labeled evolutionary epistemology of theories and understands the increase in human knowledge, such as scientific theories, as naturalistic accounts of evolution. Both, EEM and EET initially drew from the core concepts of the Modern Synthesis. Several scholars have severely criticized the analogies made between EET and the Neo-Darwinian key processes of evolution. In particular processes of random mutation, the rate of variation, natural selection as the unique driving force, and the adaptationist agenda are believed to reveal disanalogies. In contrast to the Modern Synthesis, the Extended Evolutionary Synthesis not only recognizes developmental processes but also ecological interactions and systems dynamics as well as social and cultural evolutionary reciprocity as important evolutionary processes. Concepts of the Extended Evolutionary Synthesis are therefore expected to be more fruitful for re-conceptualizing parallels between scientific theorizing and biological evolution. (shrink)

Current knowledge of the genetic, epigenetic, behavioural and symbolic systems of inheritance requires a revision and extension of the mid-twentieth-century, gene-based, 'Modern Synthesis' version of Darwinian evolutionary theory. We present the case for this by first outlining the history that led to the neo-Darwinian view of evolution. In the second section we describe and compare different types of inheritance, and in the third discuss the implications of a broad view of heredity for various aspects of evolutionary (...) theory. We end with an examination of the philosophical and conceptual ramifications of evolutionary thinking that incorporates multiple inheritance systems. (shrink)

In 1912, Julian Huxley published his first book The Individual in the Animal Kingdom which he dedicated to the then world-famous French philosopher Henri Bergson. Historians have generally adopted one of two attitudes towards Huxley’s early encounter with Bergson. They either dismiss it entirely as unimportant or minimise it, deeming it a youthful indiscretion preceding Huxley’s full conversion to Fisherian Darwinism. Close biographical study and new archive materials demonstrate, however, that neither position is tenable. The Bergsonian elements in play in (...) Julian Huxley’s early works fed into his first ideas about progress in evolution and even his celebrated theories of bird courtship. Furthermore, the view that Huxley rejected Bergson in his later years needs to be revised. Although Huxley ended up claiming that Bergson’s theory of evolution had no explanatory power, he never repudiated the descriptive power of Bergson’s controversial notion of the élan vital. Even into the Modern Synthesis period, Huxley represented his own synthesis as drawing decisively on Bergson’s philosophy. (shrink)

In this article I will analyze whether the so-called Extended Evolutionary Synthesis represents a synthesis and an extension with respect to its predecessor, Modern Synthesis. It will be argued that the MS proposes an externalist approach to evolution while the EES considers it necessary to overcome the internalism/externalism dichotomy by proposing more integrative approaches. It will be concluded that the EES cannot be considered an extension of MS and that the appeal to that extension is (...) related to sociological aspects and the epistemic value of theoretical unification that was always present in biological evolutionary thinking. (shrink)

In this article I will analyze whether the so-called Extended Evolutionary Synthesis represents a synthesis and an extension with respect to its predecessor, Modern Synthesis. It will be argued that the MS proposes an externalist approach to evolution while the EES considers it necessary to overcome the internalism/externalism dichotomy by proposing more integrative approaches. It will be concluded that the EES cannot be considered an extension of MS and that the appeal to that extension is (...) related to sociological aspects and the epistemic value of theoretical unification that was always present in biological evolutionary thinking. (shrink)

I propose we abandon the unit concept of "the evolutionary synthesis". There was much more to evolutionary studies in the 1920s and 1930s than is suggested in our commonplace narratives of this object in history. Instead, four organising threads capture much of evolutionary studies at this time. First, the nature of species and the process of speciation were dominating, unifying subjects. Second, research into these subjects developed along four main lines, or problem complexes: variation, divergence, isolation, (...) and selection. Some calls for 'synthesis' focused on these problem complexes (sometimes on one of these; other times, all). In these calls, comprehensive and pluralist compendia of plausibly relevant elements were preferred over reaching consensus about the value of particular formulae. Third, increasing confidence in the study of common problems coincided with methodological and epistemic changes associated with experimental taxonomy. Finally, the surge of interest in species problems and speciation in the 1930s is intimately tied to larger trends, especially a shifting balance in the life sciences towards process-based biologies and away from object-based naturalist disciplines. Advocates of synthesis in evolution supported, and were adapting to, these larger trends. (shrink)

Evolutionary biology is a field currently animated by much discussion concerning its conceptual foundations. On the one hand, we have supporters of a classical view of evolutionary theory, whose backbone is provided by population genetics and the so-called Modern Synthesis (MS). On the other hand, a number of researchers are calling for an Extended Synthe- sis (ES) that takes seriously both the limitations of the MS (such as its inability to incorporate developmental biology) and recent empirical (...) and theoretical research on issues such as evolvability, modularity, and self-organization. In this article, I engage in an in-depth commentary of an influential paper by population geneticist Michael Lynch, which I take to be the best defense of the MS-population genetics position published so far. I show why I think that Lynch’s arguments are wanting and propose a modification of evolutionary theory that retains but greatly expands on population genetics. (shrink)

One foundational question in contemporarybiology is how to `rejoin evolution anddevelopment. The emerging research program(evolutionary developmental biology or`evo-devo) requires a meshing of disciplines,concepts, and explanations that have beendeveloped largely in independence over the pastcentury. In the attempt to comprehend thepresent separation between evolution anddevelopment much attention has been paid to thesplit between genetics and embryology in theearly part of the 20th century with itscodification in the exclusion of embryologyfrom the Modern Synthesis. This encourages acharacterization of evolutionary (...) developmentalbiology as the marriage of evolutionary theoryand embryology via developmental genetics. Butthere remains a largely untold story about thesignificance of morphology and comparativeanatomy (also minimized in the ModernSynthesis). Functional and evolutionarymorphology are critical for understanding thedevelopment of a concept central toevolutionary developmental biology,evolutionary innovation. Highlighting thediscipline of morphology and the concepts ofinnovation and novelty provides an alternativeway of conceptualizing the `evo and the `devoto be synthesized. (shrink)

The extensive range and depth of the twenty commentaries on my target article confirms that something has gone deeply wrong in biology. A wide range of biologists has more than met my invitation for “others to pitch in and develop or counter my arguments.” The commentaries greatly develop those arguments. Also remarkably, none raise issues I would seriously disagree with. I will focus first on the more critical comments, summarise the other comments, and then point the way forward on what (...) I view as a necessary and long-overdue transition in the foundations of biology. (shrink)

Evolutionary theory is undergoing an intense period of discussion and reevaluation. This, contrary to the misleading claims of creationists and other pseudoscientists, is no harbinger of a crisis but rather the opposite: the field is expanding dramatically in terms of both empirical discoveries and new ideas. In this essay I briefly trace the conceptual history of evolutionary theory from Darwinism to neo-Darwinism, and from the Modern Synthesis to what I refer to as the Extended Synthesis, (...) a more inclusive conceptual framework containing among others evo–devo, an expanded theory of heredity, elements of complexity theory, ideas about evolvability, and a reevaluation of levels of selection. I argue that evolutionary biology has never seen a paradigm shift, in the philosophical sense of the term, except when it moved from natural theology to empirical science in the middle of the 19th century. The Extended Synthesis, accordingly, is an expansion of the Modern Synthesis of the 1930s and 1940s, and one that—like its predecessor—will probably take decades to complete. (shrink)

In the received view of the history of the Modern Evolutionary Synthesis, paleontology was given a prominent role in evolutionary biology thanks to the significant influence of paleontologist George Gaylord Simpson on both the institutional and conceptual development of the Synthesis. Simpson's 1944 Tempo and Mode in Evolution is considered a classic of Synthesis-era biology, and Simpson often remarked on the influence of other major Synthesis figures – such as Ernst Mayr and Theodosius (...) Dobzhansky – on his developing thought. Why, then, did paleontologists of the 1970s and 1980s – Stephen Jay Gould, Niles Eldredge, David M. Raup, Steven Stanley, and others – so frequently complain that paleontology remained marginalized within evolutionary biology? This essay considers three linked questions: first, were paleontologists genuinely welcomed into the Synthetic project during its initial stages? Second, was the initial promise of the role for paleontology realized during the decades between 1950 and 1980, when the Synthesis supposedly "hardened" to an "orthodoxy"? And third, did the period of organized dissent and opposition to this orthodoxy by paleontologists during the 1970s and 1980s bring about a long-delayed completion to the Modern Synthesis, or rather does it highlight the wider failure of any such unified Darwinian evolutionary consensus? (shrink)

We trace the history of the Modern Evolutionary Synthesis, and of genetic Darwinism generally, with a view to showing why, even in its current versions, it can no longer serve as a general framework for evolutionary theory. The main reason is empirical. Genetical Darwinism cannot accommodate the role of development (and of genes in development) in many evolutionary processes. We go on to discuss two conceptual issues: whether natural selection can be the “creative factor” in (...) a new, more general framework for evolutionary theorizing; and whether in such a framework organisms must be conceived as self-organizing systems embedded in self-organizing ecological systems. (shrink)

The question of whether the modern evolutionary synthesis requires an extension has recently become a topic of discussion, and a source of controversy. We suggest that this debate is, for the most part, not about the modern synthesis at all. Rather, it is about the extent to which genetic mechanisms can be regarded as the primary determinants of phenotypic characters. The modern synthesis has been associated with the idea that phenotypes are the result (...) of gene products, while supporters of the extended synthesis have suggested that environmental factors, along with processes such as epigenetic inheritance, and niche construction play an important role in character formation. We argue that the methodology of the modern evolutionary synthesis has been enormously successful, but does not provide an accurate characterization of the origin of phenotypes. For its part, the extended synthesis has yet to be transformed into a testable theory, and accordingly, has yielded few results. We conclude by suggesting that the origin of phenotypes can only be understood by integrating findings from all levels of the organismal hierarchy. In most cases, parts and processes from a single level fail to accurately explain the presence of a given phenotypic trait. The debate between the proponents of the modern and extended syntheses is somewhat reminiscent of the duck-rabbit illusion. The two sides are probably talking about the same thing, but from different perspectives. If not, then we argue that the challenge is to do an experiment that rules out the alternative view. (shrink)

Huxley coined the phrase, the “evolutionary synthesis” to refer to the acceptance by a vast majority of biologists in the mid-20th Century of a “synthetic” view of evolution. According to this view, natural selection acting on minor hereditary variation was the primary cause of both adaptive change within populations and major changes, such as speciation and the evolution of higher taxa, such as families and genera. This was, roughly, a synthesis of Mendelian genetics and Darwinian evolutionary (...) theory; it was a demonstration that prior barriers to understanding between various subdisciplines in the life sciences could be removed. The relevance of different domains in biology to one another was established under a common research program. The evolutionary synthesis may be broken down into two periods, the “early” synthesis from 1918 through 1932, and what is more often called the “modern synthesis” from 1936-1947. The authors most commonly associated with the early synthesis are J.B.S. Haldane, R.A. Fisher, and S. Wright. These three figures authored a number of important synthetic advances; first, they demonstrated the compatibility of a Mendelian, particulate theory of inheritance with the results of Biometry, a study of the correlations of measures of traits between relatives. Second, they developed the theoretical framework for evolutionary biology, classical population genetics. This is a family of mathematical models representing evolution as change in genotype frequencies, from one generation to the next, as a product of selection, mutation, migration, and drift, or chance. Third, there was a broader synthesis of population genetics with cytology, genetics, and biochemistry, as well as both empirical and mathematical demonstrations to the effect that very small selective forces acting over a relatively long time were able to generate substantial evolutionary change, a novel and surprising result to many skeptics of Darwinian gradualist views. The later “modern” synthesis is most often identified with the work of Mayr, Dobzhansky and Simpson. There was a major institutional change in biology at this stage, insofar as different subdisciplines formerly housed in different departments, and with different methodologies were united under the same institutional umbrella of “evolutionary biology.” Mayr played an important role as a community architect, in founding the Society for the Study of Evolution, and the journal Evolution, which drew together work in systematics, biogeography, paleontology, and theoretical population genetics. (shrink)

Since the 1940s, microbiologists, biochemists and population geneticists have experimented with the genetic mechanisms of microorganisms in order to investigate evolutionary processes. These evolutionary studies of bacteria and other microorganisms gained some recognition from the standard-bearers of the modern synthesis of evolutionary biology, especially Theodosius Dobzhansky and Ledyard Stebbins. A further period of post-synthesis bacterial evolutionary research occurred between the 1950s and 1980s. These experimental analyses focused on the evolution of population and genetic (...) structure, the adaptive gain of new functions, and the evolutionary consequences of competition dynamics. This large body of research aimed to make evolutionary theory testable and predictive, by giving it mechanistic underpinnings. Although evolutionary microbiologists promoted bacterial experiments as methodologically advantageous and a source of general insight into evolution, they also acknowledged the biological differences of bacteria. My historical overview concludes with reflections on what bacterial evolutionary research achieved in this period, and its implications for the still-developing modern synthesis. (shrink)

I argue that Darwinian evolutionary theory has a rhetorical dimension and that rhetorical criticism plays a role in how evolutionary science acquires knowledge. I define what I mean by rhetoric by considering Darwin’s Origin. I use the Modern Evolutionary Synthesis to show how rhetoric conceived as situated and addressed argumentation enters into evolutionary theorizing. Finally, I argue that rhetorical criticism helps judge the success, limits, and failures of these theories.

Ernst Mayr (1980) provided an influential picture of the nature of the Modern Evolutionary Synthesis and of the debate and changes occurring prior to its completion. Mayr intended his account to be applicable to comparable cases. Sociobiology should be evaluated both as a comparable case, an attempt to produce a synthesis which undergoes development of the sort Mayr described, and as an extension of the Modern Synthesis itself. Examination of what the explanatory goals and (...) development of the New Sociobiological Synthesis would be, if it is to achieve a fruitful synthesis which fits Mayr's account, undermines Richard Lewontin's critique of sociobiology. Although Lewontin speaks for many in viewing sociobiology as the latest historical manifestation of social Darwinism, genetic determinism, biological reductionism, and vulgar adaptationism, sociobiology's effort to produce a synthesis does not entail commitment to those positions. (shrink)

This paper uses formal Darwinism as elaborated by Alan Grafen to articulate an explanatory pluralism that casts light upon two strands of controversies running across evolutionary biology, viz., the place of organisms versus genes, and the role of adaptation. Formal Darwinism shows that natural selection can be viewed either physics-style, as a dynamics of alleles, or in the style of economics as an optimizing process. After presenting such pluralism, I argue first that whereas population genetics does not support optimization, (...) optimality can still be taken as a default hypothesis when modeling evolutionary processes; and second, that organisms have an explanatory role in evolutionary theory, since they are involved in the economic perspective of optimization. Finally, in order to ask whether the Modern Synthesis can indeed provide a theory of organisms, I apply a Kantian-inspired theoretical view of organisms (underlying much developmental modeling), according to which they are both designed entities and subjects of intrinsic circular processes involving the whole organism and its parts. I first show that the design aspect is accountable for in terms of the Modern Synthesis understood in the formal Darwinism framework. I then question whether the latter aspect of organisms can also be ultimately captured in the same framework, and to this purpose devise an empirical test relying on an assessment of the relative weight of genetic elements in developmental and functional gene regulatory networks. (shrink)

This paper locates the contributions of Kauffman and Ayala to this symposium in the context of recent discussions of the adequacy of the Modern Synthesis. The neglect of morphology and development described by Kauffman is understandable in view of the belief that selection is the most powerful evolutionary force. His idea that properties of order may be explained by nonselective mechanisms is also examined. The paper subsequently takes up Ayala's criticism of S.J. Gould's view that macroevolution is (...) a process "decoupled" from microevolution. It is argued that the idea of species selection makes Gould's antireductionism ontological in character; this contrasts with Ayala's contention that the decoupling is merely epistemological. (shrink)

The debate of nativisim versus empiricism is over the relative importance of evolutionary versus ontogenetic mechanisms. This is mostly seen today as a false dichotomy. The synthesis of these positions provides a modern viewpoint of grounded category formation. This combined view places equal importance on feedback between these levels in guiding development, and is more appropriately compared to culturalist positions.

The modern synthesis in evolutionary biology is taken to be that period in which a consensus developed among biologists about the major causes of evolution, a consensus that informed research in evolutionary biology for at least a half century. As such, it is a particularly fruitful period to consider when reflecting on the meaning and role of chance in evolutionary explanation. Biologists of this period make reference to “chance” and loose cognates of “chance,” such as: (...) “random,” “contingent,” “accidental,” “haphazard,” or “stochastic.” Of course, what an author might mean by “chance” in any specific context varies. -/- In the following, we first offer a historiographical note on the synthesis. Second, we introduce five ways in which synthesis authors spoke about chance. We do not take these to be an exhaustive taxonomy of all possible ways in which chance meaningfully figures in explanations in evolutionary biology. These are simply five common uses of the term by biologists at this period. They will serve to organize our summary of the collected references to chance and the analysis and discussion of the following questions: • What did synthesis authors understand by chance? • How did these authors see chance operating in evolution? • Did their appeals to chance increase or decrease over time during the synthesis? That is, was there a “hardening” of the synthesis, as Gould claimed (1983)? (shrink)

Darwin proposed that evolutionary novelties are environmentally induced in organisms “constitutionally” sensitive to environmental change, with selection effective owing to the inheritance of constitutional responses. A molecular theory of inheritance, pangenesis , explained the cross‐generational transmission of environmentally induced traits, as required for evolution by natural selection. The twentieth‐century evolutionary synthesis featured mutation as the source of novelty, neglecting the role of environmental induction. But current knowledge of environmentally sensitive gene expression, combined with the idea of genetic (...) accommodation of mutationally and environmentally induced change, supports a revival of Darwin's original theory that is consistent with modern molecular and population genetics. †To contact the author, please write to: Smithsonian Tropical Research Institute, c/o Escuela de Biología, Universidad de Costa Rica, Costa Rica; e‐mail: [email protected]. (shrink)

Since its origin in the early 20th century, the modern synthesis theory of evolution has grown to represent the orthodox view on the process of organic evolution. It is a powerful and successful theory. Its defining features include the prominence it accords to genes in the explanation of development and inheritance, and the role of natural selection as the cause of adaptation. Since the advent of the 21st century, however, the modern synthesis has been subject to (...) repeated and sustained challenges. In the last two decades, evolutionary biology has witnessed unprecedented growth in the understanding of those processes that underwrite the development of organisms and the inheritance of characters. The empirical advances usher in challenges to the conceptual foundations of evolutionary theory. Many current commentators charge that the new biology of the 21st century calls for a revision, extension, or wholesale rejection of the modern synthesis theory of evolution. Defenders of the modern synthesis maintain that the theory can accommodate the exciting new advances in biology, without forfeiting its central precepts. The original essays collected in this volume—by evolutionary biologists, philosophers of science, and historians of biology—survey and assess the various challenges to the modern synthesis arising from the new biology of the 21st century. Taken together, the essays cover a spectrum of views, from those that contend that the modern synthesis can rise to the challenges of the new biology, with little or no revision required, to those that call for the abandonment of the modern synthesis. (shrink)

A central reason that undergirds the significance of evo-devo is the claim that development was left out of the Modern synthesis. This claim turns out to be quite complicated, both in terms of whether development was genuinely excluded and how to understand the different kinds of embryological research that might have contributed. The present paper reevaluates this central claim by focusing on the practice of model organism choice. Through a survey of examples utilized in the literature of the (...) Modern synthesis, I identify a previously overlooked feature: exclusion of research on marine invertebrates. Understanding the import of this pattern requires interpreting it in terms of two epistemic values operating in biological research: theoretical generality and explanatory completeness. In tandem, these values clarify and enhance the significance of this exclusion. The absence of marine invertebrates implied both a lack of generality in the resulting theory and a lack of completeness with respect to particular evolutionary problems, such as evolvability and the origin of novelty. These problems were salient to embryological researchers aware of the variation and diversity of larval forms in marine invertebrates. In closing, I apply this analysis to model organism choice in evo-devo and discuss its relevance for an extended evolutionary synthesis. (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.

In this paper, I present an argument that quantitative behavioural analysis can be used in zoosemiotic studies to advance the field of biosemiotics. The premise is that signs and signals form patterns in space and time, which can be measured and analysed mathematically. Whole organism sign processing is an important component of the semiosphere, with individual organisms in their Umwelten deriving signs from, and contributing to, the semiosphere, and vice versa. Moreover, there is a wealth of data available in the (...) traditional ethology literature which can be reinterpreted semiotically and drawn together to make a cohesive biosemiotic whole. For example, isolated signals, such as structural elements of birdsong, are attributed meaning by an interpreter, thus generating new ideas and hypotheses in both biology and semiotics. Furthermore, animal behaviour science has developed numerous test paradigms that with careful adaptation, could be suitable for use within a Peircean tripartite model, and thus give valuable insights into Umwelten of other species. In my conclusion, I suggest that by bringing together traditional ethology and biosemiotics, it is possible to use the Modern Synthesis to provide context to biosemiosis, thus pragmatic meaning to animal signals. On this basis, I propose updating the Modern Synthesis to a Semiotic Modern Synthesis, which focuses on whole-organism signals and their contexts, the latter being derived from neo-Darwinian theory and the ‘Umwelt’. Thus, there need be no dichotomy; the Modern Synthesis can successfully be integrated with biosemiotics. (shrink)

This chapter contains sections titled: Introduction The Evolving Evolutionary Synthesis Population Genetics vs. Developmental Genetics Evo‐Devo's Central Target: The Study of Evolvability Origins? Conclusion Postscript: Counterpoint Acknowledgments References.

The Modern Synthesis has been receiving bad press for some time now. Back in 1983, in an article entitled “The Hardening of the Modern Synthesis” Stephen Jay Gould criticized the way the Modern Synthesis had developed since its inception in the 1930s and early 1940s (Gould 1983). Back then, those who would later become known as ‘architects’ of the synthesis were united in their call for explaining evolution at all levels in terms of (...) causation at one level: genetics. What drove changes in gene frequency remained an open question. It could be mainly selection, or drift, or some (other) form of constraint. But in the two decades that followed, the synthesis underwent a major change. By the late 1940s the synthesis had ‘hardened’ around adaptationism, according to Gould. Influential contributors like Dobzhansky, Simpson and Wright had increasingly expressed adaptationist views in the later editions of their landmark books. Not because evidence had piled up, showing that selection was in fact pervasive. Instead, Gould argued, adaptationist tendencies had been preserved by some kind of cultural inertia, and were now being revived. “Certain ‘national styles’ persisted from the eighteenth century, through Darwin’s era, and into our own time. Views on adaptation provide a good example” (Gould 1983). Gould did not just argue that some form of adaptationism had resurfaced. He became well-known for his efforts to intervene on this status quo by attempting to make evolutionary biology more ‘pluralistic’. In collaborative work with Richard Lewontin (Gould and Lewontin 1979), Elisabeth Vrba (Gould and Vrba 1982; Vrba and Gould 1986) and Niles Eldredge (Eldredge and Gould 1972; Gould and Eldredge 1977) he criticized the synthesis for its adaptationism and its lack of appreciation for hierarchical perspectives. Gould exerted his influence in a different way as well. Together with Eldredge, he had facsimiles reprinted of the first editions of two books that had shaped synthesis, but with their own critical introductions (Eldredge 1982; Gould 1982). Dobzhansky’s Genetics and the Origin of Species and Mayr’s Systematics and the Origin of Species appeared as reprints in the ‘Columbia Classics in Evolution’ series, sending an unambiguous message to the readers: these are foundational works, but they have been superseded. In the summer of 2008, some 25 years after Gould made his point about the hardening of the Modern Synthesis, a group of sixteen biologists and philosophers gathered at the Konrad Lorenz Institute for Evolution and Cognition Research (KLI) near Vienna, Austria, to discuss cutting-edge research that reaches beyond the synthesis framework. Before it even started, this workshop on the ‘Extended Synthesis’ had already attracted a fair share of attention in the blogosphere and had resulted in a news feature in Science (Pennisi 2008). After the meeting, Nature weighed in on the matter (Whitfield 2008). The results of over 3 days of presentations and extensive discussion have now been published as Evolution—The Extended Synthesis. 1 The publication of this collection of sixteen essays is accompanied by the republication of Julian Huxley’s Evolution: The Modern Synthesis; the book that introduced the term ‘Modern Synthesis’. Both books are introduced by the organizers of the KLI workshop, Massimo Pigliucci and Gerd Müller. Like Gould and Eldredge before them, Pigliucci and Müller did not reissue one of the canons of the Modern Synthesis without giving the readers some ‘guidance’. Starting with the cover, the editors proclaim boldly that this is ‘the definitive edition’ of Huxley’s book. In a new foreword, they sketch the context in which the book was written and assess some of its features. They voice some mild criticism of alleged ‘adaptationism’. But their tone is different from that of Gould and Eldredge. Pigliucci and Müller praise Huxley for his pluralistic outlook, which has again become essential in the forging of an Extended Synthesis. That makes Huxley’s book more than just an interesting but obsolete classic. Instead, it can teach valuable lessons about how to ‘soften up’ a synthesis that has become hardened over time. (shrink)

Noble rightly emphasizes that some modern evolutionary biologists´ neglect of agency is consequential with regard to our understanding of the natural world and real-world ecological developments. I elaborate on biosemiotic ideas on semiotic agency and explain how organisms can change the environment by way of semiotic causation. I also comment on the human language’s role in human Umwelten, and how our linguistically mediated reality can be self-deceptive – as if we lived in a bubble of our own making. (...) Finally, I indicate how we can make the Umwelt bubble of the Modern Synthesis burst. (shrink)

The development of modern evolutionary ethics began shortly after the publication of Charles Darwin's On the Origin of Species by Natural Selection. Early discussions were plagued by several problems. First, evolutionary ethical explanations were dependent on group-selection accounts of social behavior (especially the explanation of altruism). Second, they seem to violate the philosophical principle that “ought” statements cannot be derived from “is” statements alone (values cannot be derivedfrom facts alone). Third, evolutionary ethics appeared to be biologically (...) deterministic, deemed incompatible with the free will required for ethics to be possible. Fourth, social policies based on evolutionary theory (for example, eugenics in the early part of this century) seemed patently unethical. Sociobiology (which coalesced as a field of study with Edward O. Wilson's Sociobiology: The New Synthesis, 1975) addressed several of these problems and provided a rich framework and a new impetus for evolutionary ethics. The lingering problems were the philosophical is-ought barrier and biological determinism. After tracing the early and more recent development of evolutionary ethics, I argue that the remaining problems can be surmounted and an incipient evolutionary ethics can be defended. Thoroughgoing evolutionaryethics must await theoretical developments in neurobiology and cognitive science. (shrink)

This paper examines the history of animal behavior studies after the synthesis period. Three episodes are considered: the adoption of the theory of natural selection, the mathematization of ideas, and the spread of molecular methods in behavior studies. In these three episodes, students of behavior adopted practices and standards developed in population ecology and population genetics. While they borrowed tools and methods from these fields, they made distinct uses that set them relatively apart and led them to contribute, in (...) their own way, to evolutionary theory. These episodes also highlight some limitations of “conjunction narratives” centered on the relation between a discipline and the modern synthesis. A trend in conjunction narratives is to interpret any development related to evolution in a discipline as an “extension,” an “integration,” or as a “delayed” synthesis. I here suggest that this can lead to underestimate discontinuities in the history of evolutionary biology. (shrink)

In the six decades since the publication of Julian Huxley's Evolution: The Modern Synthesis, spectacular empirical advances in the biological sciences have been accompanied by equally significant developments within the core theoretical framework of the discipline. As a result, evolutionary theory today includes concepts and even entire new fields that were not part of the foundational structure of the Modern Synthesis. In this volume, sixteen leading evolutionary biologists and philosophers of science survey the conceptual (...) changes that have emerged since Huxley's landmark publication, not only in such traditional domains of evolutionary biology as quantitative genetics and paleontology but also in such new fields of research as genomics and EvoDevo. Most of the contributors to Evolution—The Extended Synthesis accept many of the tenets of the classical framework but want to relax some of its assumptions and introduce significant conceptual augmentations of the basic Modern Synthesis structure—just as the architects of the Modern Synthesis themselves expanded and modulated previous versions of Darwinism. This continuing revision of a theoretical edifice the foundations of which were laid in the middle of the nineteenth century—the reexamination of old ideas, proposals of new ones, and the synthesis of the most suitable—shows us how science works, and how scientists have painstakingly built a solid set of explanations for what Darwin called the "grandeur" of life. (shrink)