Phenotypic Evolution explicitly recognizes organisms as complex genetic-epigenetic systems developing in response to changing internal and external environments. As a key to a better understanding of how phenotypes evolve, the authors have developed a framework that centers on the concept of the Developmental Reaction Norm. This encompasses their views: (1) that organisms are better considered as integrated units than as disconnected parts (allometry and phenotypic integration); (2) that an understanding of ontogeny is vital for evaluating evolution (...) of adult forms (ontogenetic trajectories, epigenetics, and constraints); and (3) that environmental heterogeneity is ubiquitous and must be acknowledged for its pervasive role in phenotypic expression. (shrink)

A foundational idea of evo‐devo is that morphological variation is not isotropic, that is, it does not occur in all directions. Instead, some directions of morphological variation are more likely than others from DNA‐level variation and these largely depend on development. We argue that this evo‐devo perspective should apply not only to morphology but to evolution at all phenotypic levels. At other phenotypic levels there is no development, but there are processes that can be seen, in analogy (...) to development, as constructing the phenotype (e.g., protein folding, learning for behavior, etc.). We argue that to explain the direction of evolution two types of arguments need to be combined: generative arguments about which phenotypic variation arises in each generation and selective arguments about which of it passes to the next generation. We explain how a full consideration of the two types of arguments improves the explanatory power of evolutionary theory. Also see the video abstract here: https://youtu.be/Egbvma_uaKc. (shrink)

During the last two decades the role of quantitative genetics in evolutionary theory has expanded considerably. Quantitative genetic-based models addressing long term phenotypic evolution, evolution in multiple environments (phenotypic plasticity) and evolution of ontogenies (developmental trajectories) have been proposed. Yet, the mathematical foundations of quantitative genetics were laid with a very different set of problems in mind (mostly the prediction of short term responses to artificial selection), and at a time in which any details of (...) the genetic machinery were virtually unknown. In this paper we discuss what a model is in population biology, and what kind of model we need in order to address the complexities of phenotypic evolution. We review the assumptions of quantitative genetics and its most recent accomplishments, together with the limitations that such assumptions impose on the modelling of some aspects of phenotypic evolution. We also discuss three alternative appr oaches to the theoretical description of evolutionary trajectories (nonlinear dynamics, complexity theory and optimization theory), and their respective advantages and limitations. We conclude by calling for a new theoretical synthesis, including quantitative genetics and not necessarily limited to the other approaches here discussed. (shrink)

Phenotypic integration refers to the study of complex patterns of covariation among functionally related traits in a given organism. It has been investigated throughout the 20th century, but has only recently risen to the forefront of evolutionary ecological research. In this essay, I identify the reasons for this late flourishing of studies on integration, and discuss some of the major areas of current endeavour: the interplay of adaptation and constraints, the genetic and molecular bases of integration, the role of (...) phenotypic plasticity, macroevolutionary studies of integration, and statistical and conceptual issues in the study of the evolution of complex phenotypes. I then conclude with a brief discussion of what I see as the major future directions of research on phenotypic integration and how they relate to our more general quest for the understanding of phenotypic evolution within the neo-Darwinian framework. I suggest that studying integration provides a particularly stimulating and truly interdisciplinary convergence of researchers from fields as disparate as molecular genetics, developmental biology, evolutionary ecology, palaeontology and even philosophy of science. (shrink)

The study of phenotypic plasticity has progressed significantly over the past few decades. We have moved from variation for plasticity being considered as a nuisance in evolutionary studies to it being the primary target of investigations that use an array of methods, including quantitative and molecular genetics, as well as of several approaches that model the evolution of plastic responses. Here, I consider some of the major aspects of research on phenotypic plasticity, assessing where progress has been (...) made and where additional effort is required. I suggest that some areas of research, such the study of the quantitative genetic underpinning of plasticity, have been either settled in broad outline or superseded by new approaches and questions. Other issues, such as the costs of plasticity are currently at the forefront of research in this field, and are likely to be areas of major future development. (shrink)

A new voice in the nature-nurture debate can be heard at the interface between evolution and development. Phenotypic integration is a major growth area in research.

It is common in attempts to extend the theory of evolution to culture to generalize from the causal basis of biological evolution, so that evolutionary theory becomes the theory of copying processes. Generalizing from the formal dynamics of evolution allows greater leeway in what kinds of things cultural entities can be, if they are to evolve. By understanding the phenomenon of cultural transmission in terms of coordinated phenotypic variability, we can have a theory of cultural (...) class='Hi'>evolution which allows us to avoid the various difficulties with the elaboration of informational entities such as the cultural replicator, or meme. Such an account is a boon to the project of evolutionary epistemology since it confirms the presumption in favor of the general adaptiveness of culture, illuminating rather than obscuring the inherent intimacy of our relationship to (e.g.) our ideas. (shrink)

Mathematical modeling can ground communication and reciprocal enrichment among fields of knowledge whose domains are very different. We propose a new mathematical model applicable in biology, specified into ecology and evolutionary biology, and in cultural transmission studies, considered as a branch of economics. Main inspiration for the model are some biological concepts we call “eco-phenotypic” such as development, plasticity, reaction norm, phenotypic heritability, epigenetics, and niche construction. “Physiology” is a core concept we introduce and translate differently in the (...) biological and cultural domains. The model is ecological in that it aims at describing and studying organisms and populations that perform living, intended as a thermodynamic, matter-energy process concerning resources gathering, usage, and depletion in a spatiotemporal context with given characteristics, as well as with multiplication and space occupation. The model also supports evolution, intended as a dynamics including cumulative change in the features of unique organisms that are connected into breeding populations. The model is then applicable to the economics of cultural transmission in which individuals form their attitudes and patterns of behavior under a complex system of influences derived from their “cultural parents”, other members of the society, and the environment. On the side of biology, an innovative goal is to integrate in a single model all the eco-phenotypic concepts as well as both evolution and ecology. On the side of cultural transmission, eco-phenotypic modeling seems more appropriate in capturing some aspects of cultural systems which are modeled away in the earlier framework based on Mendelian population genetics. (shrink)

The paper describes the context and the origin of a particular debate that concerns the evolution of phenotypic plasticity. In 1965, British biologist A. D. Bradshaw proposed a widely cited model intended to explain the evolution of norms of reaction, based on his studies of plant populations. Bradshaw’s model went beyond the notion of the “adaptive norm of reaction” discussed before him by Dobzhansky and Schmalhausen by suggesting that “plasticity” the ability of a phenotype to be modified (...) by the environment should be genetically determined. To prove Bradshaw’s hypothesis, it became necessary for some authors to identify the pressures exerted by natural selection on phenotypic plasticity in particular traits, and thus to model its evolution. In this paper, I contrast two different views, based on quantitative genetic models, proposed in the mid-1980s: Russell Lande and Sara Via’s conception of phenotypic plasticity, which assumes that the evolution of plasticity is linked to the evolution of the plastic trait itself, and Samuel Scheiner and Richard Lyman’s view, which assumes that the evolution of plasticity is independent from the evolution of the trait. I show how the origin of this specific debate, and different assumptions about the evolution of phenotypic plasticity, depended on Bradshaw’s definition of plasticity and the context of quantitative genetics. (shrink)

Evolution by natural selection has been extended to several supraorganismic levels, but whether it can apply to ecosystems remains controversial on two main counts. First, local ecosystems are loosely individuated, so that it is unclear how they manifest heredity and fitness. Second, even if they did, the meta-ecosystem formed by this population of local ecosystems will also suffer from a very low degree of cohesion, which will jeopardize any ENS. We suggest a way to overcome both issues, focusing on (...) ecosystem properties rather than on ecosystemic individuals. First, we follow recent theoretical developments which deny the centrality of reproduction in ENS. This leads us to merge heredity and fitness in a single process, in which a local ecosystem causally influences its neighbors, in a way responsible for their phenotypic similarity. Second, we suggest that the resulting meta-ecosystem need not meet the criteria of individuality. Instead, the evolving meta-ecosystem is best understood as a homeostatic property cluster, i.e., a set of phenotypes that together evolve by ENS at the ecosystem level. We illustrate this conceptual framework with a hypothetical example of local ecosystems that vary in terms of stability, productivity, diversity, and complementarity between species. Finally, we stress that our property-based account of ecosystemic ENS can help understand evolution at other biological levels, such as early life evolution and holobionts. (shrink)

Against the neo-Darwinian assumption that genetic factors are the principal source of variation upon which natural selection operates, a phenotype-first hypothesis strikes us as revolutionary because development would seem to constitute an independent source of variability. Richard Watson and his co-authors have argued that developmental memory constitutes one such variety of phenotypic variability. While this version of the phenotype-first hypothesis is especially well-suited for the late metazoan context, where animals have a sufficient history of selection from which to draw, (...) appeals to developmental memory seem less plausible in the evolutionary context of the early metazoans. I provide an interpretation of Stuart Newman’s account of deep metazoan phylogenesis that suggests that spandrels are, in addition to developmental memory, an important reservoir of phenotypic variability. I conclude by arguing that Gerd Müller’s “side-effect hypothesis” is an illuminating generalization of the proposed non-Watsonian version of the phenotype-first hypothesis. (shrink)

I identify six types of phenotypic plasticity and categorize them with respect to their cognitive status. I look at differences and relations between some of these types of plasticity and then analyze how phenotypic outcomes are transmitted across generations. I engage with the relevant literature on developmental scaffolding and entrenchment in cultural evolution. I argue that that the typology I present here can be beneficial for such a debate and therefore instructive to better comprehend the evolution (...) and development of human cognition. (shrink)

Evolutionary biology is paying increasing attention to the mechanisms that enable phenotypic plasticity, evolvability, and extra‐genetic inheritance. Yet, there is a concern that these phenomena remain insufficiently integrated within evolutionary theory. Understanding their evolutionary implications would require focusing on phenotypes and their variation, but this does not always fit well with the prevalent genetic representation of evolution that screens off developmental mechanisms. Here, we instead use development as a starting point, and represent it in a way that allows (...) genetic, environmental and epigenetic sources of phenotypic variation to be independent. We show why this representation helps to understand the evolutionary consequences of both genetic and non‐genetic phenotype determinants, and discuss how this approach can instigate future areas of empirical and theoretical research. (shrink)

In addition to considerable debate in the recent evolutionary literature about the limits of the Modern Synthesis of the 1930s and 1940s, there has also been theoretical and empirical interest in a variety of new and not so new concepts such as phenotypic plasticity, genetic assimilation and phenotypic accommodation. Here we consider examples of the arguments and counter- arguments that have shaped this discussion. We suggest that much of the controversy hinges on several misunderstandings, including unwarranted fears of (...) a general attempt at overthrowing the Modern Synthesis paradigm, and some fundamental conceptual confusion about the proper roles of phenotypic plasticity and natural selection within evolutionary theory. (shrink)

An exploration of the nexus between ecology, evolutionary biology and molecular biology, via the concept of phenotypic plasticity.

In recent years philosophers have attempted to clarify the units of selection controversy in evolutionary biology by offering conceptual analyses of the term 'unit of selection'. A common feature of many of these analyses is an emphasis on the claim that units of selection are entities exhibiting heritable variation in fitness. In this paper I argue that the demand that units of selection be characterized in terms of heritability is unnecessary, as well as undesirable, on historical, theoretical, and philosophical grounds. (...) I propose a positive account of the proper referent of the term 'unit of selection', distinguishing between the processes of evolution and phenotypic selection. The main result of this analysis is greater clarity about the conceptual structure of evolutionary theory. (shrink)

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

Background: One of the all-time questions in evolutionary biology regards the evolution of organismal shapes, and in particular why certain forms appear repeatedly in the history of life, others only seldom and still others not at all. Recent research in this field has deployed the conceptual framework of constraints and natural selection as measured by quantitative genetic methods. Scope: In this paper I argue that quantitative genetics can by necessity only provide us with useful statistical sum- maries that may (...) lead researchers to formulate testable causal hypotheses, but that any inferential attempt beyond this is unreasonable. Instead, I suggest that thinking in terms of coordinates in phenotypic spaces, and approaching the problem using a variety of empirical methods (seeking a consilience of evidence), is more likely to lead to solid inferences regarding the causal basis of the historical patterns that make up most of the data available on phenotypic evolution. (shrink)

Phenotypic plasticity integrates the insights of ecological genetics, developmental biology, and evolutionary theory. Plasticity research asks foundational questions about how living organisms are capable of variation in their genetic makeup and in their responses to environmental factors. For instance, how do novel adaptive phenotypes originate? How do organisms detect and respond to stressful environments? What is the balance between genetic or natural constraints (such as gravity) and natural selection? The author begins by defining phenotypic plasticity and detailing its (...) history, including important experiments and methods of statistical and graphical analysis. He then provides extended examples of the molecular basis of plasticity, the plasticity of development, the ecology of plastic responses, and the role of costs and constraints in the evolution of plasticity. A brief epilogue looks at how plasticity studies shed light on the nature/nurture debate in the popular media. (shrink)

My aim in this paper is to demonstrate that a very simple learning rule based on imitation can help to sustain altruism as a culturally transmitted pattern or behaviour among agents playing a standard prisoner’s dilemma game. The point of this demonstration is not to prove that imitation is single-handedly responsible for existing levels of altruism (a thesis that is false), nor is the point to show that imitation is an important factor in explanations for the evolution of altruism (...) (a thesis already prominent in the existing literature). The point is to show that imitation contributes to the evolution of altruism in a particular way that is not always fairly represented by evolutionary game theory models. Specifically, the paper uses a simple model to illustrate that cultural transmission includes mechanisms that do not transmit phenotype vertically (i.e. from parent to related offspring) and that these mechanisms can promote altruism in the absence of any direct biological propensity favouring such behaviour. This is a noteworthy result because it shows that evolutionary models can be built to explicitly reflect the contribution of non-vertical transmission in our explanations for the evolution of altruism among humans and other social species. (shrink)

Is integrative biology a good idea, or even possible? There has been much interest lately in the unifica- tion of biology and the integration of traditionally separate disciplines such as molecular and develop- mental biology on one hand, and ecology and evolutionary biology on the other. In this paper I ask if and under what circumstances such integration of efforts actually makes sense. I develop by example an analogy with Aristotle’s famous four “causes” that one can investigate concerning any object (...) or phenomenon: material (what something is made of), formal (what distinguishes that particular object from others), efficient (how was the object made) and final (why was the object made). The example is provided by ongoing research on different aspects of flowering time in the model system Arabidop- sis, a small weed belonging to the mustard family. I show that understanding how flowering time is controlled is an epistemologically different sort of question from why and how it evolved, and that the two research agendas can be pursued largely independently of each other. Toward the end, I propose that the real goal of integrative biology is to understand the boundary layers between levels of biologi- cal analysis, something to which modern philosophy of science can contribute significantly. (shrink)

The current implementation of the Neo-Darwinian model of evolution typically assumes that the set of possible phenotypes is organized into a highly symmetric and regular space. Most conveniently, a Euclidean vector space is used, representing phenotypic properties by real-valued variables. Computational work on the biophysical genotype-phenotype model of RNA folding, however, suggests a rather different picture. If phenotypes are organized according to genetic accessibility, the resulting space lacks a metric and can be formalized only in terms of a (...) relatively unfamiliar structure. Patterns of phenotypic evolution—such as punctuation, irreversibility, and modularity—result naturally from the properties of the genotype-phenotype map, which, given the genetic accessibility structure, define accessibility in the phenotype space. The classical framework, however, addresses these patterns exclusively in terms of natural selection on suitably constructed fitness landscapes. Recent work has extended the explanatory level for phenotypic evolution from fitness considerations alone to include the topological structure of phenotype space as induced by the genotype-phenotype map. Lewontin’s notion of “quasi-independence” of characters can also be formalized in topological terms: it corresponds to the assumption that a region of the phenotype space is represented by a product space of orthogonal factors. In this picture, each character corresponds to a factor of a region of the phenotype space. We consider any region of the phenotype space that has a given factorization as a “type”, i.e., as a set of phenotypes that share the same set of phenotypic characters. Thus, a theory of character identity can be developed that is based on the correspondence of local factors in different regions of the phenotype space. (shrink)

Behavioral genetics and cultural evolution have both revolutionized our understanding of human behavior – largely independent of each other. Here, we reconcile these two fields under a dual inheritance framework, offering a more nuanced understanding of the interaction between genes and culture. Going beyond typical analyses of gene–environment interactions, we describe the cultural dynamics that shape these interactions by shaping the environment and population structure. A cultural evolutionary approach can explain, for example, how factors such as rates of innovation (...) and diffusion, density of cultural subgroups, and tolerance for behavioral diversity impact heritability estimates, thus yielding predictions for different social contexts. Moreover, when cumulative culture functionally overlaps with genes, genetic effects become masked, unmasked, or even reversed, and the causal effects of an identified gene become confounded with features of the cultural environment. The manner of confounding is specific to a particular society at a particular time, but a WEIRD (western, educated, industrialized, rich, and democratic) sampling problem obscures this boundedness. Cultural evolutionary dynamics are typically missing from models of gene-to-phenotype causality, hindering generalizability of genetic effects across societies and across time. We lay out a reconciled framework and use it to predict the ways in which heritability should differ between societies, between socioeconomic levels, and other groupings within some societies but not others, and over the life course. An integrated cultural evolutionary behavioral genetic approach cuts through the nature–nurture debate and helps resolve controversies in topics such as IQ. (shrink)

The paper aims at proposing an extended notion of epigenesis acknowledging an actual causal import to the phenotypic dimension for the evolutionary diversification of life forms. “Introductory remarks” section offers introductory remarks on the issue of epigenesis contrasting it with ancient and modern preformationist views. In “Transmutation of forms: phenotypic variation, diversification, and complexification” section we propose to intend epigenesis as a process of phenotypic formation and diversification dependent on environmental influences, independent of changes in the genomic (...) nucleotide sequence, and occurring during the whole life span. Then, “Evolvability and phenotypic evolution” section focuses on phenotypic plasticity and offers an overview of basic properties that allows biological systems to be evolvable—i.e. to have the potentiality of producing phenotypic variation. Successively, the emphasis is put on environmentally-induced modifications in the regulation of gene expression giving rise to phenotypic variation and diversification. After some brief considerations on the debated issue of epigenetic inheritance, the issue of culture is considered. The key point is that, in the case of humans and of the evolutionary history of the genus Homo at least, the environment is also, importantly, the cultural environment. Thus, “Bio-cultural feedback” section argues that a bio-cultural feedback should be acknowledged in the “epigenic” processes leading to phenotypic diversification and innovation in Homo evolution. Finally, “Brain plasticity and cultural neural reuse” section introduces the notion of “cultural neural reuse”, which refers to phenotypic/neural modifications induced by specific features of the cultural environment that are effective in human cultural evolution without involving genetic changes. Therefore, cultural neural reuse may be regarded as a key instance of the bio-cultural feedback and ultimately of the extended notion of epigenesis proposed in this work. (shrink)

Observing adaptive evolution is difficult. In the fossil record, phenotypic evolution happens much more slowly than in artificial selection experiments or in experimental evolution. Yet measures of selection on phenotypic traits, with high heritabilities, suggest that phenotypic evolution should also be rapid in the wild, and this discrepancy often remains even after accounting for correlations between different traits (i.e. making predictions using the multivariate version of the breeder's equation). Are fitness correlations with quantitative (...) traits adequate measures of selection in the wild? We should instead view fitnesses as average properties of genotypes, while acknowledging that they can be environment‐dependent. Populations will tend to remain at fitness equilibria, once these are attained, and phenotypes will then be stable. Thus, studying the causes of adaptive change at a genotypic rather than phenotypic level may reveal that, typically, it is occurring too slowly to be easily observed. (shrink)

The ‘phenotypic gambit,’ the assumption that we can ignore genetics and look at the fitness of phenotypes to determine the expected evolutionary dynamics of a population, is often used in evolutionary game theory. However, as this paper will show, an overlooked genotype to phenotype map can qualitatively affect evolution in ways the phenotypic approach cannot predict or explain. This gives us reason to believe that, even in the long-term, correspondences between phenotypic predictions and dynamical outcomes are (...) not robust for all plausible assumptions regarding the underlying genetics of traits. This paper shows important ways in which the phenotypic gambit can fail and how to proceed with evolutionary game theoretic modeling when it does. (shrink)

Co-creating knowledge takes a new approach to human phenotypic morality as a biologically based, human lineage specific trait. Authors from very different backgrounds first review research on the nature and origins of morality using the social brain network, and studies of individuals who cannot “know good” or think morally because of brain dysfunction. They find these models helpful but insufficient, and turn to paleoanthropology, cognitive science, and neuroscience to understand human moral capacity and its origins long ago, in the (...) genus Homo. An unusual narrative capturing “morality in action” takes the reader back 900,000 years, and then the authors analyze the essential features of moral thinking and behavior as expressed by early and later species on our lineage. In what has primarily been the province of philosophers to date, the authors’ morality model is presented for further scientific testing. (shrink)

Extending the approach to a ‘theology of science’ developed in Faith and Wisdom in Science, I expand its theme of the tension between chaos and emergent order, within the arc of the Biblical story of creation, towards a theology of evolutionary science. In addition to the material in Job, the book of Wisdom provides a remarkable account of transmutation of species, within a recapitulation of the Exodus theme, that I juxtapose with a modern genotype-phenotype theory of evolutionary dynamics, exploiting analogies (...) with statistical mechanics. The dual and connected structures of microscopic and macroscopic provide a locus for the Joban tensions of chaos and emergent order, and provide an interpretative narrative for the emergent directionality of evolution, and a theology that situates within a creation of freedom to explore the potential of the created order. (shrink)

The aim of this contribution is to investigate certain selected parts of the extended evolutionary synthesis which all have a common denominator, namely evolution by meaning attribution. We start by arguing that living organisms can manipulate and interpret their genetic script via epigenetic modifications in a semiotic manner, that is, by meaning attribution. Genes do not build living beings to be transmitted to future generations. Genes have been shaped by evolution as a memory medium that is transmitted from (...) one generation to the next, but the actual reading of such scripts is modified by momentary contexts. Secondly, we show that phenotypic evolution variously re-uses already existing homologies which in evolving systems acquire a new meaning. We also suggest that the ways in which organisms perceive their environment and other living beings is an important but still largely neglected evolutionary force. Variations in perception influence the direction and intensity of sexual selection and some behaviourally mediated regimes of natural selection. Thirdly, we point out that especially if we want to study their evolution, living beings should not be considered in isolation but in their mutual coexistence, in their historically established being together. Recent attempts to view living beings as constructors of niches and holobionts seem compatible with the classical Umwelt theory. This approach seems capable of accounting for both competitiveness and cooperation, thus making the overall image of evolution more comprehensive. And finally, we argue that if we want to expand our understanding of biological evolution, in addition to variation, selection, and inheritance we also need to take into account processes which participate in meaning attribution. (shrink)

Despite a large and multifaceted effort to understand the vast landscape of phenotypic data, their current form inhibits productive data analysis. The lack of a community-wide, consensus-based, human- and machine-interpretable language for describing phenotypes and their genomic and environmental contexts is perhaps the most pressing scientific bottleneck to integration across many key fields in biology, including genomics, systems biology, development, medicine, evolution, ecology, and systematics. Here we survey the current phenomics landscape, including data resources and handling, and the (...) progress that has been made to accurately capture relevant data descriptions for phenotypes. We present an example of the kind of integration across domains that computable phenotypes would enable, and we call upon the broader biology community, publishers, and relevant funding agencies to support efforts to surmount today's data barriers and facilitate analytical reproducibility. (shrink)

Over the past twenty years, the role of phenotypic plasticity in Darwinian evolution has become a hotly debated topic among biologists and philosophers of science. For instance, in the Extended Evolutionary Synthesis, a new form of evolutionary theory that aims to include processes not taken into account by standard theory (the Modern Synthesis), the question of the remarkable plasticity of living beings is central. Beyond Lamarckism, Plasticity in Darwinian Evolution shows that the evolutionary impact of plasticity was (...) in fact debated long before the emergence of the current debate on the limits of the Modern Synthesis. The question of how the plasticity of organisms could play a causal role in Darwinian evolution was raised on two separate occasions. First, around 1900, with the emergence of the theory of "organic selection". Second, during the formation of the Modern Synthesis itself, in the mid-20th century. Out of these reflections came a very large number of concepts, models, and many different terms ("organic selection", "stabilizing selection", "genetic assimilation", "Baldwin effect", etc.), which were often developed independently in various research traditions and empirical contexts. This book also looks at the reasons why these conceptions have been downplayed in the standard understanding of adaptive evolution. Showing the extraordinary complexity of this history, Beyond Lamarckism is aimed at readers interested in evolutionary theory, whether philosophers, biologists or historians. (shrink)

This volume explores from multiple perspectives the subtle and interesting relationship between the theory of rational choice and Darwinian evolution. In rational choice theory, agents are assumed to make choices that maximize their utility; in evolution, natural selection 'chooses' between phenotypes according to the criterion of fitness maximization. So there is a parallel between utility in rational choice theory and fitness in Darwinian theory. This conceptual link between fitness and utility is mirrored by the interesting parallels between formal (...) models of evolution and rational choice. The essays in this volume, by leading philosophers, economists, biologists and psychologists, explore the connection between evolution and rational choice in a number of different contexts, including choice under uncertainty, strategic decision making and pro-social behaviour. They will be of interest to students and researchers in philosophy of science, evolutionary biology, economics and psychology. (shrink)

We propose a conceptual model that maps the causal pathways relating biological evolution to cultural change. It builds on conventional evolutionary theory by placing emphasis on the capacity of organisms to modify sources of natural selection in their environment (niche construction) and by broadening the evolutionary dynamic to incorporate ontogenetic and cultural processes. In this model, phenotypes have a much more active role in evolution than generally conceived. This sheds light on hominid evolution, on the evolution (...) of culture, and on altruism and cooperation. Culture amplifies the capacity of human beings to modify sources of natural selection in their environments to the point where that capacity raises some new questions about the processes of human adaptation. Key Words: adaptation; altruism; cooperation; evolutionary psychology; gene-culture coevolution; human evolution; human genetics; niche construction; sociobiology. (shrink)

The paper addresses a central problem in evolutionary biology and cognitive science; evolution of a neural based learning phenotype from a structured genotype. It describes morphogenesis of a neural network-based cognitive system, starting from a single genotype having a modulon control structure. It further shows how such a system, denoted as GALA architecture, growing its own recurrent axon connections, can further develop into various structures capable of learning in different learning modes, such as advice learning, reinforcement learning, and emotion (...) learning. The paper particularly considers the emotion learning systems and their motivational structure. A simulation experiment is provided to illustrate the theoretical issues discussed. (shrink)

We have values and aspirations. What of other animals? Are their "values" different from ours? Animals manifestly prefer having plenty of food to starvation, and comfort to pain, and they will work hard to obtain a mate. But beyond these "creature comforts," they seem to be largely indifferent to the prospects and anxieties that make up human life. A suitable coverall term for human aspiration would be the pursuit of happiness, bearing in mind that happiness is many different things to (...) different people. This already sets us aside from our fellow creatures. To put it vividly, Mother Nature doesn't care whether we are happy--but we care (and Mother Nature doesn't care that we care). That is, it would be naive to suppose that the process of natural selection has somehow endorsed our pursuit of happiness as the proximal mechanism for maximizing our genetic fitness. It is consistent with what we know of evolution to suppose that the process of natural selection--Mother Nature--would design us to experience however much anxiety and torment is consistent with making more grandchildren. Our values are, like everything else in our extended phenotypes, products of evolutionary processes, but we misread them if we see them to be just like the "values" of other animals, which can indeed be viewed as the straightforward result of Mother Nature's project of installing an optimally reliable fitness-enhancing set of preferences. The difference arises, I will argue, from the fact that we have culture, and culture provides a medium in which a radically different--indeed, orthogonal--set of selection pressures can re-direct evolutionary processes into unprecedented channels. (shrink)

We review the evolution of domestic animals, emphasizing the effect of the earliest steps of domestication on its course. Using the first domesticated species, the dog (Canis familiaris), for illustration, we describe the evolutionary peculiarities during the historical domestication, such as the high level and wide range of diversity. We suggest that the process of earliest domestication via unconscious and later conscious selection of human‐defined behavioral traits may accelerate phenotypic variations. The review is based on the results of (...) a long‐term experiment designed to reproduce early mammalian domestication in the silver fox (Vulpes vulpes) selected for tameability or amenability to domestication. We describe changes in behavior, morphology and physiology that appeared in the fox during its selection for tameability, which were similar to those observed in the domestic dog. Based on the data of the fox experiment and survey of relevant data, we discuss the developmental, genetic and possible molecular genetic mechanisms underlying these changes. We ascribe the causative role in evolutionary transformation of domestic animals to the selection for behavior and to the neurospecific regulatory genes it affects. (shrink)

In The Selfish Gene, Richard Dawkins crystallized the gene's eye view of evolution developed by W.D. Hamilton and others. The book provoked widespread and heated debate. Written in part as a response, The Extended Phenotype gave a deeper clarification of the central concept of the gene as the unit of selection; but it did much more besides. In it, Dawkins extended the gene's eye view to argue that the genes that sit within an organism have an influence that reaches (...) out beyond the visible traits in that body - the phenotype - to the wider environment, which can include other individuals. So, for instance, the genes of the beaver drive it to gather twigs to produce the substantial physical structure of a dam; and the genes of the cuckoo chick produce effects that manipulate the behaviour of the host bird, making it nurture the intruder as one of its own. This notion of the extended phenotype has proved to be highly influential in the way we understand evolution and the natural world. It represents a key scientific contribution to evolutionary biology, and it continues to play an important role in research in the life sciences. The Extended Phenotype is a conceptually deep book that forms important reading for biologists and students. But Dawkins' clear exposition is accessible to all who are prepared to put in a little effort. Oxford Landmark Science books are 'must-read' classics of modern science writing which have crystallized big ideas, and shaped the way we think. (shrink)

A framework is presented in which the role ofdevelopmental rules in phenotypic evolution canbe studied for some simple situations. Usingtwo different implicit models of development,characterized by different developmental mapsfrom genotypes to phenotypes, it is shown bysimulation that developmental rules and driftcan result in directional phenotypic evolutionwithout selection. For both models thesimulations show that the critical parameterthat drives the final phenotypic distributionis the cardinality of the set of genotypes thatmap to each phenotype. Details of thedevelopmental map do (...) not matter. If phenotypesare randomly assigned to genotypes, the lastresult can also be proved analytically. (shrink)

How to use a model organism to study phenotypic integration and constraints on evolution.

The recent sociobiology debate has raised fundamental and previously unresolved conceptual problems. Evolutionary Instability - Logical and Material Aspects of a Unified Theory of Biosocial Evolution - offers ap- proaches for their solution. The scientific applications comprise the dynamics and evolutionary instability of hierarchically organized systems, especially systems of interacting behavioural phenotypes in animals and man. The technical apparatus is thoroughly explained in intuitive terms within the text, and illustrated by numerous familiar examples and graphical representations, supplemented by an (...) informal summary and discussion. The analyses offer new theoretical perspectives to such diverse fields as philosophy of science, evolutionary biology, general system theory and sociology. (shrink)

Nelson and Winter’s An Evolutionary Theory of Economic Change (1982) was the foundational work of what has become the thriving sub-discipline of evolutionary economics. In attempting to develop an alternative to neoclassical economics, the authors looked to borrow basic ideas from biology, in particular a concept of economic “natural selection.” However, the evolutionary models they construct in their seminal work are in many respects quite different from the models of evolutionary biology. There is no reproduction in any usual sense, “mutation” (...) is directed as opposed to blind, and there is no meaningful distinction between phenotype and genotype. Despite these substantial departures from the conceptions of evolutionary biology, I argue that the “evolutionary” economics of Nelson and Winter is indeed a legitimate extension of Darwinian evolutionary principles to a novel domain, and that the traditional conception of evolution by natural selection must be revised. The novel features of evolutionary economics models reflect the distinctive theoretical requirements faced by economists. I further contend that reproduction, heredity, blind variation, and the genotype/phenotype distinction are all inessential to evolutionary theory, and that their role in evolutionary biology is a domain-specific feature of biological theory. (shrink)

DNA sequence variation is abundant in wild populations. While molecular biologists use genetically homogeneous strains of model organisms to avoid this variation, evolutionary biologists embrace genetic variation as the material of evolution since heritable differences in fitness drive evolutionary change. Yet, the relationship between the phenotypic variation affecting fitness and the genotypic variation producing it is complex. Genetic buffering mechanisms modify this relationship by concealing the effects of genetic and environmental variation on phenotype. Genetic buffering allows the build-up (...) and storage of genetic variation in phenotypically normal populations. When buffering breaks down, thresholds governing the expression of previously silent variation are crossed. At these thresholds, phenotypic differences suddenly appear and are available for selection. Thus, buffering mechanisms modulate evolution and regulate a balance between evolutionary stasis and change. Recent work provides a glimpse of the molecular details governing some types of genetic buffering. BioEssays 22:1095–1105, 2000. © 2000 John Wiley & Sons, Inc. (shrink)

Darwin's “mystery of mysteries,” the origin of species, is caused by the evolution of speciation phenotypes, i.e. phenotypic differences that depress gene flow between daughter species during speciation. Postmating, prezygotic (PMPZ) differentiation characterizes many closely related species causing conspecific sperm precedence (CSP), wherein a female preferentially utilizes conspecific over heterospecific sperm in fertilization. Until recently, the components of CSP have been difficult to observe and study in internally fertilizing organisms. Research into the mechanisms of CSP is now progressing (...) rapidly with the help of new innovative research tools. With the recent development of a sperm labeling system enabling distinct labels for different males, direct observations of competing male sperm within the female reproductive tract are possible, revealing multiple PMPZ phenotypes that combine to cause CSP. The discovery of mechanisms underlying CSP predicts an exciting future for studies of PMPZ speciation phenotypes and possible general principles underlying the origin of species. (shrink)

A response to Via about the existence (or not) and role of plasticity genes in evolution.