According to many biologists, explaining the evolution of morphological novelty and behavioral innovation are central endeavors in contemporary evolutionary biology. These endeavors are inherently multidisciplinary but also have involved a high degree of controversy. One key source of controversy is the definitional diversity associated with the concept of evolutionary novelty, which can lead to contradictory claims (a novel trait according to one definition is not a novel trait according to another). We argue that this diversity should (...) be interpreted in light of a different epistemic role played by the concept of evolutionary novelty—the structuring of a problem space or setting of an explanatory agenda—rather than the concept’s capacity to categorize traits as novel. This distinctive role is consistent with the definitional diversity and shows that the concept of novelty benefits ongoing investigation by focusing attention on answering different questions related to comprehending the origins of novelty. A review of recent theoretical and empirical work on evolutionary novelty confirms this interpretation. (shrink)

Accounting for the evolutionary origins of morphological novelty is one of the core challenges of contemporary evolutionary biology. A successful explanatory framework requires the integration of different biological disciplines, but the relationships between developmental biology and standard evolutionary biology remain contested. There is also disagreement about how to define the concept of evolutionary novelty. These issues were the subjects of a workshop held in November 2009 at the University of Alberta. We report on the (...) discussion and results of this workshop, addressing questions about (i) how to define evolutionary novelty and understand its significance, (ii) how to interpret evolutionary developmental biology as a synthesis and its relation to neo-Darwinian evolutionary theory, and (iii) how to integrate disparate biological approaches in general. (shrink)

We study the effects of environmental catastrophes on the evolution of a population of sensory-motor agents with individually evolving mutation rates, and compare these effects in a variety of control systems. A catastrophe makes the balance shift toward the need for evolutionary novelty, and we observe the mutation rate evolve upwards. As the population adapts the sensory-motor strategies to the new environment and the balance shifts toward a need for evolutionary memory, the mutation rate falls. These observations (...) support the hypothesis that second-order evolution of the mutation flexibly balances the need for evolutionary “novelty” and “memory,” both of which are controlled by the mutation rate. (shrink)

A central topic in research at the intersection of development and evolution is the origin of novel traits. Despite progress on understanding how developmental mechanisms underlie patterns of diversity in the history of life, the problem of novelty continues to challenge researchers. Here we argue that research on evolutionary novelty and the closely associated phenomenon of co-option can be reframed fruitfully by: (1) specifying a conceptual model of mechanisms that underwrite character identity, (2) providing a richer and (...) more empirically precise notion of co-option that goes beyond common appeals to “deep homology”, and (3) attending to the nature of experimental interventions that can determine whether and how the co-option of identity mechanisms can help to explain novel character origins. This reframing has the potential to channel future investigation to make substantive progress on the problem of evolutionary novelty. To illustrate this potential, we apply our reframing to two case studies: treehopper helmets and beetle horns. (shrink)

It has been argued by Hull and others that a remnant of essentialism impeded taxonomic progress until systematists abandoned attempting to define taxa on the basis of characters necessary and sufficient for group membership. The advent of cladistics suggests instead that it is an essentialistic view of characters, not of taxa, that should be abandoned, and that only a transformational view of characters allows evolutionary novelties to be identified, much less explained. Conventional Darwinian explanations are not tautologous but are (...) difficult to test and scarcely explain evolutionary novelties, probably because of their emphasis on genetic rather than epigenetic (developmental) processes. (shrink)

The idea of phenotypic novelty appears throughout the evolutionary literature. Novelties have been defined so broadly as to make the term meaningless and so narrowly as to apply only to a limited number of spectacular structures. Here I examine some of the available definitions of phenotypic novelty and argue that the modern synthesis is ill equipped at explaining novelties. I then discuss three frameworks that may help biologists get a better insight of how novelties arise during evolution (...) but warn that these frameworks should be considered in addition to, and not as potential substitutes of, the modern synthesis. †To contact the author, please write to: Departments of Ecology and Evolution and Philosophy, Stony Brook University, Stony Brook, NY 11794; e‐mail: [email protected]. (shrink)

Many philosophers of biology have embraced a version of pluralism in response to the failure of theory reduction but overlook how concepts, methods, and explanatory resources are in fact coordinated, such as in interdisciplinary research where the aim is to integrate different strands into an articulated whole. This is observable for the origin of evolutionary novelty—a complex problem that requires a synthesis of intellectual resources from different fields to arrive at robust answers to multiple allied questions. It is (...) an apt locus for exploring new dimensions of explanatory integration because it necessitates coordination among historical and experimental disciplines . These coordination issues are widespread for the origin of novel morphologies observed in the Cambrian Explosion. Despite an explicit commitment to an integrated, interdisciplinary explanation, some potential disciplinary contributors are excluded. Notable among these exclusions is the physics of ontogeny. We argue that two different dimensions of integration—data and standards—have been insufficiently distinguished. This distinction accounts for why physics-based explanatory contributions to the origin of novelty have been resisted: they do not integrate certain types of data and differ in how they conceptualize the standard of uniformitarianism in historical, causal explanations. Our analysis of these different dimensions of integration contributes to the development of more adequate and integrated explanatory frameworks. (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)

In evolutionary medicine and other related fields, the concept of evolutionary mismatch is used to explain phenomena whereby traits reduce in adaptive value and eventually become maladaptive as the environment changes. This article argues that there is a similar problem of persistent adaptivity—what has been called the problem of evolutionary novelty—and it introduces the concept of mismatch resistance in order to explain phenomena whereby traits retain their adaptive value in novel environments that are radically different from (...) the organisms’ environment of evolutionary adaptedness (EEA). The possible role of variability selection in the evolution of mismatch-resistant traits is discussed, and it is suggested that mismatch resistance provides a useful tool for making progress on certain issues related to evolutionary theory, such as the modularity debate, cases of adaptivity outside of organisms’ ancestral environment, and the viability of naturalism as an overarching philosophical framework for understanding the natural world. (shrink)

This thematic issue addresses questions of constraints on the evolution of form—physical, biological, and technical. Here, form is defined as an embodiment of a specific structure, which can be hierarchically different yet emerge from the same processes. The focus of this contribution is about how developmental biology and paleontology can be better integrated and compared in order to produce hypotheses about the evolution of form. The constraints on current EvoDevo research stem from the disconnect in the focus of study for (...) developmental geneticists and evolutionary morphologists; the former being interested in early developmental events at a molecular level in a model animal, the latter in late developmental events or comparison between adult forms, at a structural level in non-model animals. In order to truly integrate information from both fields in our understanding of evolutionary processes, morphology needs to be reintegrated in the study of gene expression, and its time frame needs to be extended beyond early developmental stages. Gene expression in non-model organisms also needs to be studied in order to gain perspective into primitive patterning at evolutionary nodes. Hypotheses formed by the comparison of expression patterns and morphologies seen in extant species can then be tested against forms found in the fossil record, coming closer to understanding the mechanisms underlying evolution. (shrink)

Given the pervasiveness of gene sharing in evolution and the extent of homology across the tree of life, why is everything not homologous with everything else? The continuity and overlapping genetic contributions to diverse traits across lineages seem to imply that no discrete determination of homology is possible. Although some argue that the widespread overlap in parts and processes should be acknowledged as “partial” homology, this threatens a broad base of presumed comparative morphological knowledge accepted by most biologists. Following a (...) long scientific tradition, we advocate a strategy of “theoretical articulation” that introduces further distinctions to existing concepts to produce increased contrastive resolution among the labels used to represent biological phenomena. We pursue this strategy by drawing on successful patterns of reasoning from serial homology at the level of gene sequences to generate an enriched characterization of serial homology as a hierarchical, phylogenetic concept. Specifically, we propose that the concept of serial homology should be applied primarily to repeated but developmentally individualized body parts, such as cell types, differentiated body segments, or epidermal appendages. For these characters, a phylogenetic history can be reconstructed, similar to families of paralogous genes, endowing the notion of serial homology with a hierarchical, phylogenetic interpretation. On this basis, we propose a five-fold theoretical classification that permits a more fine-grained mapping of diverse trait-types. This facilitates answering the question of why everything is not homologous with everything else, as well as how novelty is possible given that any new character possesses evolutionary precursors. We illustrate the fecundity of our account by reference to debates over insect wing serial homologs and vertebrate paired appendages. (shrink)

Comprehending the origin of marine invertebrate larvae remains a key domain of research for evolutionary biologists, including the repeated origin of direct developmental modes in echinoids. In order to address the latter question, we surveyed existing evidence on relationships of homology between the ectoderm territories of two closely related sea urchin species in the genus Heliocidaris that differ in their developmental mode. Additionally, we explored a recently articulated idea about homology called ‘organizational homology’ (Muller 2003. In: Muller GB, Newman (...) SA, editors. Origination of organismal form: beyond the gene in developmental and evolutionary biology. Cambridge, MA: A Bradford Book, The MIT Press. p 51–69. ) in the context of this specific empirical case study. Applying the perspective of organizational homology to our experimental system of congeneric echinoids has led us to a new hypothesis concerning the ectoderm evolution in these species. The extravestibular ectoderm of the direct developer Heliocidaris erythrogramma is a novel developmental territory that arose as a fusion of the oral and aboral ectoderm territories found in indirect developing echinoids such as Heliocidaris tuberculata. This hypothesis instantiates a theoretical principle concerning the origin of developmental modules, ‘integration’, which has been neglected because the opposite theoretical principle, ‘parcellation’, is more readily observable in events such as gene duplication and divergence (Wagner 1996. Am Zool 36:36–43). J. Exp. Zool. (Mol. Dev. Evol.) 306B:18– 34, 2006. (shrink)

It is widely accepted that stressful conditions can facilitate evolutionary change. The mechanisms elucidated thus far accomplish this with a generic increase in heritable variation that facilitates more rapid adaptive evolution, often via plastic modifications of existing characters. Through scrutiny of different meanings of stress in biological research, and an explicit recognition that stressors must be characterized relative to their effect on capacities for maintaining functional integrity, we distinguish between: (1) previously identified stress-responsive mechanisms that facilitate evolution by maintaining (...) an adaptive fit with the environment, and (2) the co-option of stress-responsive mechanisms that are specific to stressors leading to the origin of novelties via compensation. Unlike standard accounts of gene co-option that identify component sources of evolutionary change, our model documents the cost-benefit trade-offs and thereby explains how one mechanism—an immediate response to acute stress—is transformed evolutionarily into another—routine protection from recurring stressors. We illustrate our argument with examples from cell type origination as well as processes and structures at higher levels of organization. These examples suggest a general principle of evolutionary origination based on the capacity to switch between regulatory states related to reproduction and proliferation versus survival and differentiation. (shrink)

Although the role of morphology in evolutionary theory remains a subject of debate, assessing the contributions of morphological investigation to evolutionary developmental biology (Evo-devo) is a more circumscribed issue of direct relevance to ongoing research. Historical studies of morphologically oriented researchers and the formation of the Modern Synthesis in the Anglo-American context identify a recurring theme: the synthetic theory of evolution did not capture multiple levels of biological organization. When this feature is incorporated into a philosophical framework for (...) explaining the origin of evolutionary innovations and novelties (a core domain of inquiry in Evo-devo) two specific roles for morphology can be described: (1) the conceptualization and operational identification of the targets of explanation; and (2) the elucidation of causal interactions at higher levels of organization during ontogeny and through evolutionary time. These roles are critical components of any adequate explanation of innovation and novelty though not exhaustive of the parts played by morphology in evolutionary investigation. They also invite reflection on what counts as an evolutionary cause in contemporary evolutionary biology. (shrink)

It is a common complaint that antireductionist arguments are primarily negative. Here I describe an alternative nonreductionist epistemology based on considerations taken from multidisciplinary research in biology. The core of this framework consists in seeing investigation as coordinated around sets of problems (problem agendas) that have associated criteria of explanatory adequacy. These ideas are developed in a case study, the explanation of evolutionary innovations and novelties, which demonstrates the applicability and fruitfulness of this nonreductionist epistemological perspective. This account also (...) bears on questions of conceptual change and theory structure in philosophy of science. †To contact the author, please write to: Department of Philosophy, University of Minnesota, 831 Heller Hall, 271 19th Ave. S., Minneapolis, MN 55455; e‐mail: [email protected]. (shrink)

When the environment in which an organism lives deviates in some essential way from that to which it is adapted, this is described as “evolutionary mismatch,” or “evolutionary novelty.” The notion of mismatch plays an important role, explicitly or implicitly, in evolution-informed cognitive psychology, clinical psychology, and medicine. The evolutionary novelty of our contemporary environment is thought to have significant implications for our health and well-being. However, scientists have generally been working without a clear definition (...) of mismatch. This paper defines mismatch as deviations in the environment that render biological traits unable, or impaired in their ability, to produce their selected effects. The machinery developed by Millikan in connection with her account of proper function, and with her related teleosemantic account of representation, is used to identify four major types, and several subtypes, of evolutionary mismatch. While the taxonomy offered here does not in itself resolve any scientific debates, the hope is that it can be used to better formulate empirical hypotheses concerning the effects of mismatch. To illustrate, it is used to show that the controversial hypothesis that general intelligence evolved as an adaptation to handle evolutionary novelty can, contra some critics, be formulated in a conceptually coherent way. (shrink)

Knives, birds' wings, and mountain slopes are used for certain purposes: cutting, flying, and climbing. A bird's wings have in common with knives that they have been 'designed' for the purpose they serve, which purpose accounts for their existence, whereas mountain slopes have come about by geological processes independently of their uses for climbing. A bird's wings differ from a knife in that they have not been designed or produced by any conscious agent; rather, the wings, like the slopes, are (...) outcomes of natural processes without any intentional causation. Evolutionary biologists use teleological language and teleological explanations. I propose that this use is appropriate, because teleological explanations are hypotheses that can be subject to empirical testing. The distinctiveness of teleological hypotheses is that they account for the existence of a feature in terms of the function it serves; for example, wings have evolved and persist because flying is beneficial to birds by increasing their chances of surviving and reproducing. Features of organisms that are explained with teleological hypotheses include structures, such as wings; processes, such as development from egg to adult; and behaviours, such as nest building. A proximate explanation of these features is the function they serve; an ultimate explanation that they all share is their contribution to the reproductive fitness of the organisms. I distinguish several kinds of teleological explanations, such as natural and artificial, as well as bounded and unbounded, some of which but not others apply to biological explanations. (shrink)

occurs first. The biological debate is conducted largely on a theoretical level. In this paper, I undertake to locate
the reason for the difference in temporal ordering. The question is whether the difference depends on alternative
interpretations of empirical data, on differing views about evolutionary mechanisms, or on different conceptual
frameworks. It will turn out that the latter is the case and that discerning two different notions of novelty solves
the apparent contradiction. Both concepts may apply to different cases in evolution. To (...) settle the dispute by
judging whether any of both concepts is empty or not has to be recommitted to science. (shrink)

Evolutionary developmental biology (Evo-devo) is a loose conglomeration of research programs in the life sciences with two main axes: (a) the evolution of development, or inquiry into the pattern and processes of how ontogeny varies and changes over time; and, (b) the developmental basis of evolution, or inquiry into the causal impact of ontogenetic processes on evolutionary trajectories—both in terms of constraint and facilitation. Philosophical issues are found along both axes surrounding concepts such as evolvability, novelty, and (...) modularity. The developmental basis of evolution has garnered much attention because it speaks to the possibility of revising a standard construal of evolutionary theory, but the evolution of development harbors its own conceptual questions. This article addresses the heterogeneity of Evo-devo’s conglomerate structure (including disagreements over its individuation), as well as the concepts and controversies of philosophical interest pertaining to the evolution of development and the developmental basis of evolution. Future research will benefit from a shift away from global theorizing toward the scientific practices of Evo-devo. (shrink)

Organisms and their genomes are mosaics of features of different evolutionary age. Older features are maintained by ‘negative’ selection and comprise part of the selective environment that has shaped the evolution of newer features by ‘positive’ selection. Body plans and body parts are among the most conservative elements of the environment in which genetic differences are selected. By this process, well-trodden paths of development constrain and direct paths of evolutionary change. Structuralism and adaptationism are both vindicated. Form plays (...) a selective role in the molding of form. (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 1981 Dahlem conference was a catalyst for contemporary evolutionary developmental biology (Evo-devo). This introductory chapter rehearses some of the details of the history surrounding the original conference and its associated edited volume, explicates the philosophical problem of conceptual change that provided the rationale for a workshop devoted to evaluating the epistemic revisions and transformations that occurred in the interim, explores conceptual change with respect to the concept of evolutionary novelty, and highlights some of the themes and (...) patterns in the different contributions to the present volume, Conceptual Change in Biology: Scientific and Philosophical Perspectives on Evolution and Development. (shrink)

In a macroevolutionary timescale, evolvability itself evolves. Lineages are sorted based on their ability to generate adaptive novelties, which leads to the optimization of their genotype-phenotype map. The system of translation of genetic or epigenetic changes to the phenotype may reach significant horizontal and vertical complexity, and may even exhibit certain aspects of learning behaviour. This continuously evolving semiotic system probably enables the origin of complex yet functional and internally compatible adaptations. However, it also has a second, “darker”, side. As (...) was pointed out by several authors, the same process gradually reduces the probability of the origination of significant evolutionary novelties. In a similar way to the evolution of societies, teachings, or languages, in which the growing number of internal linkages gradually solidifies their overall structure and the structure or interpretation of their constitutive elements, the evolutionary potential of lineages decreases during biological evolution. Possible adaptations become limited to small “peripheral” modifications. According to the Frozen Evolution theory, some of the proximate causes of this “macroevolutionary freezing” are more pronounced or present exclusively in sexual lineages. Sorting based on the highest evolvability probably leads to the establishment of certain structural features of complex organisms, e.g. the modular character of their development and morphology. However, modules also “macroevolutionary freeze” whereas the hypothetical “thawing” of modules or their novel adaptive combinations becomes rarer and rarer. Some possible ways out of this dead end include the rearrangement of individual development, e.g. neoteny, radical simplification, i.e. sacculinization, and transition to a higher level of organization, e.g. symbiosis or symbiogenesis. The evolution of evolvability is essentially a biosemiotic process situated at the intersection of the genocentric modern synthesis and the evo-devo-centric extended synthesis. Therefore, evolvability may eventually connect these three not necessarily contradictory approaches. (shrink)

Economic geographers increasingly consider the significance of history in shaping the contemporary socio-economic landscape and believe that experiences and competencies, acquired over time by individuals and entities in particular localities, to a large degree determine present configurations as well as future regional trajectories. Attempts to trace, understand, and investigate the pathways from past to present have given rise to the thriving and exciting sub-field of Evolutionary Economic Geography. EEG highlights the important factors that initiate, inhibit, or consolidate the contextual (...) settings and relationships in which regions and their respective agents, which comprise and shape economic activity and social reproduction, change over time. It has at its core the production and destruction of novelty in space, and the links between innovation and regional economic fortunes. The creation of knowledge, its movement and recombination within different regional ensembles of economic agents and institutions plays a critical role in the evolution of the space-economy. EEG provides a framework to disentangle the complexity of technological change and regional economic development based on a variety of theoretical and methodological approaches. In only a short time, EEG has established itself as a promising and rapidly evolving research framework with its focus on the driving forces of regional development across various scales and its attempt to translate findings into public policy. This book advances the theoretical foundations of EEG, and demonstrates how EEG utilises and operationalises conceptual frameworks, both established and new. Contributions also point to future research avenues and extensions of EEG, attempting to build stronger ties between theory, empirical evidence, and relevance to policy. This book was originally published as a special issue of _Regional Studies. _. (shrink)

Cultural evolutionary psychology (CEP) accounts for the cultural evolution of cognition. It is based on evolutionary psychology and cultural evolutionary theory and aims at a synthetic attempt which is achieved by what we want to call ‘generalization by recursion’. We argue in this paper that the evolutionary psychology program as a whole could greatly benefit from CEP’s generalization. As we will show, there is one theoretical element in particular, that CEP relevantly generalizes in contrast to its (...) predecessors. It comes from cultural evolutionary theory and has been referred to as the ‘dual inheritance argument’. CEP’s novelty consists in showing that not only cognitive products (‘grist’) but also cognitive mechanisms (‘mills’) are subject to cultural evolution and provides lots of empirical evidence for this claim. This account is ‘recursive’, because CEP’s generalization of the dual inheritance argument theoretically employs a recursive feedback-loop between cultural learning and cultural evolution. We also argue that this account might be considered to supersede unificatory and reductionistic efforts of its competitors, because it is stronger than purely structural or analogical unification while at the same time it is not too strong in order to fall prey to implausible reductionism. (shrink)

Günter Wagner’s Homology, Genes, and Evolutionary Innovation collects and synthesizes a vast array of empirical data, theoretical models, and conceptual analysis to set out a progressive research program with a central theoretical commitment: the genetic theory of homology. This research program diverges from standard approaches in evolutionary biology, provides sharpened contours to explanations of the origin of novelty, and expands the conceptual repertoire of evolutionary developmental biology. I concentrate on four aspects of the book in this (...) essay review: the genetic theory of homology and character identity networks; the implications for how we explain evolutionary novelties; the expanded set of concepts surrounding homology, and the epistemological conflicts between Wagner’s viewpoint and functionally-oriented evolutionary biology, as well as differences with other Evo–devo researchers. Together these have ramifications for how we interpret different explanatory approaches to evolutionary phenomena and understand relationships between the usefulness of concepts and the reality they represent. (shrink)

The origin of novel traits is what draws many to evolutionary biology, yet our understanding of the mechanisms that underlie the genesis of novelty remains limited. Here I review definitions of novelty including its relationship to homology. I then discuss how ontogenetic perspectives may allow us to move beyond current roadblocks in our understanding of the mechanics of innovation. Specifically, I explore the roles of canalization, plasticity and threshold responses during development in generating a reservoir of cryptic (...) genetic variation free to drift and accumulate in natural populations. Environmental or genetic perturbations that exceed the buffering capacity of development can then release this variation, and, through evolution by genetic accommodation, result in rapid diversification, recurrence of lost phenotypes as well as the origins of novel features. I conclude that, in our quest to understand the nature of innovation, the nature of development deserves to take center stage. BioEssays 30:432–447, 2008. © 2008 Wiley Periodicals, Inc. (shrink)

This paper responds to the essay reviews by David Haig, Alan Love and Rachel Brown of my recently published book “Homology, Genes and Evolutionary Innovation”. The issues addressed here relate to: the notion of classes and individuals, issues of explanatory value of adaptive and structuralist explanations in evolutionary biology, the role of homology in evolutionary theory, the limits of a pluralist stance vis a vis alternative explanations of homology, as well as the question whether and to what (...) extend the perspective laid out in HGEI can be or should be transferred to other branches of study, like comparative behavioral biology. (shrink)

This article reviews the recent reissuing of Richard Owen’s On the Nature of Limbs and its three novel, introductory essays. These essays make Owen’s 1849 text very accessible by discussing the historical context of his work and explaining how Owen’s ideas relate to his larger intellectual framework. In addition to the ways in which the essays point to Owen’s relevance for contemporary biology, I discuss how Owen’s unity of type theory and his homology claims about fins and limbs compare with (...) modern views. While the phenomena studied by Owen are nowadays of major interest to evolutionary developmental biology, research in evo-devo has largely shifted from homology (which was Owen’s concern) towards evolutionary novelty, e.g., accounting for fins as a novelty. Still, I argue that questions about homology are important and raise challenges even for explanations of novelty. (shrink)

Sociological, economic and evolutionary paradigms of human agency have often seen social agents either as the rational controllers of their fate or as marionettes on the strings of historical, functional or adaptive necessity. They found it therefore difficult to account for the variability, intentionality and creativity of human behaviour and for its frequently redundant or harmful results. This paper argues that human agency is a product of evolution, but that genetic variation and inheritance can only provide a limited explanation (...) of its complex nature. The primary evolutionary problem which human agents face while they are alive is not to adapt to stable environments, but to respond flexibly and creatively to a contingent, uncertain world. Variation and selection therefore take two connected but distinct forms, one external, genetic, and inherited across generations, the other internal and cognitive, and operating during the lifetime of individuals. An examination of this lived part of evolution provides a better understanding of key properties of agency. (shrink)

Evolutionary Psychology is based on the idea that the mind is a set of special purpose thinking devices or modules whose domain-specific structure is an adaptation to ancestral environments. The modular view of the mind is an uncontroversial description of the periphery of the mind, the input-output sensorimotor and affective subsystems. The novelty of EP is the claim that higher order cognitive processes also exhibit a modular structure. Autism is a primary case study here, interpreted as a developmental (...) failure of a module devoted to social intelligence or Theory of Mind. In this article I reappraise the arguments for innate modularity of TOM and argue that they fail. TOM ability is a consequence of domain general development scaffolded by early, innately specified, sensorimotor abilities. The alleged Modularity of TOM results from interpreting the outcome of developmental failures characteristic of autism at too high a level of cognitive abstraction. (shrink)

This article reviews the recent reissuing of Richard Owen’s On the Nature of Limbs and its three novel, introductory essays. These essays make Owen’s 1849 text very accessible by discussing the historical context of his work and explaining how Owen’s ideas relate to his larger intellectual framework. In addition to the ways in which the essays point to Owen’s relevance for contemporary biology, I discuss how Owen’s unity of type theory and his homology claims about fins and limbs compare with (...) modern views. While the phenomena studied by Owen are nowadays of major interest to evolutionary developmental biology, research in evo-devo has largely shifted from homology (which was Owen’s concern) towards evolutionary novelty, e.g., accounting for fins as a novelty. Still, I argue that questions about homology are important and raise challenges even for explanations of novelty. (shrink)

The emergence of novelty in the realm of the living remains, despite the long tradition of evolutionary biology, unwelcome, calling for explanation by old, established knowledge. The prevailing neodarwinian evolutionary paradigm approaches living beings as passive outcomes of external (and extraneous, hence “blind”) formative forces. Many teachings opposing Darwinism also take the existence of eternal, immutable and external laws as a necessary prerequisite. Ironically enough, authors who oppose Darwinian theory, and admit that living beings possess a “self”, (...) often accentuate internal, ideal and eternal harmony,which is incompatible with historical changes; moreover such harmony is again imposed by external, atemporal “laws”. I describe here a third approach embodied by the names of two unrelated scholars, Stuart Kauffman (biology, physics) and Juri Lotman (semiotics, culturology). Their approach suggests thatthe evolution of organisms, minds, cultures — is a continuous negotiation (semiosis) of ‘laws’, driving to ever broader spaces of freedom and constantly larger autonomy of existence. (shrink)

Although sciences are often conceptualized in terms of theory confirmation and hypothesis testing, an equally important dimension of scientific reasoning is the structure of problems that guide inquiry. This problem structure is evident in several concepts central to evolutionary developmental biology (Evo-devo)—constraints, modularity, evolvability, and novelty. Because problems play an important role in biological practice, they should be included in biological pedagogy, especially when treating the issue of scientific controversy. A key feature of resolving controversy is synthesizing methodologies (...) from different biological disciplines to generate empirically adequate explanations. Concentrating on problem structure illuminates this interdisciplinarity in a way that is often ignored when science is taught only from the perspective of theory or hypothesis. These philosophical considerations can assist life science educators in their continuing quest to teach biology to the next generation. -/- . (shrink)

How genomic innovation translates into organismal organization remains largely unanswered. Possessing the largest invertebrate nervous system, in conjunction with many species‐specific organs, coleoid cephalopods (octopuses, squids, cuttlefishes) provide exciting model systems to investigate how organismal novelties evolve. However, dissecting these processes requires novel approaches that enable deeper interrogation of genome evolution. Here, the existence of specific sets of genomic co‐evolutionary signatures between expanded gene families, genome reorganization, and novel genes is posited. It is reasoned that their co‐evolution has contributed (...) to the complex organization of cephalopod nervous systems and the emergence of ecologically unique organs. In the course of reviewing this field, how the first cephalopod genomic studies have begun to shed light on the molecular underpinnings of morphological novelty is illustrated and their impact on directing future research is described. It is argued that the application and evolutionary profiling of evolutionary signatures from these studies will help identify and dissect the organismal principles of cephalopod innovations. By providing specific examples, the implications of this approach both within and beyond cephalopod biology are discussed. (shrink)

The concept of scaffold is widespread in science and increasingly common in evolutionary biology. While this concept figures in causal explanations, it is not clear what scaffolds are and what role they play in those explanations. Here we present evolutionary scaffolding explanation as a distinct type of explanatory strategy, distinguishing it from other types of evolutionary explanation. By doing so, we clarify the meaning of “scaffold” as a causal concept and its potential contribution to accounts of (...) class='Hi'>evolutionary novelty and major transitions. (shrink)

Although there is no in-principle impediment to an EvoDevo of behavior, such an endeavor is not as straightforward as one might think; many of the key terms and concepts used in EvoDevo are tailored to suit its traditional focus on morphology, and are consequently difficult to apply to behavior. In this light, the application of the EvoDevo conceptual toolkit to the behavioral domain requires the establishment of a set of tractable concepts that are readily applicable to behavioral characters. Here, I (...) begin the type of theoretical work that needs to be undertaken in order to achieve this, focusing in particular on the key concept of “novelty.” Building on existing criteria used for the identification of behavioral homology from behavioral ecology, I develop a set of operational criteria for identifying novelty in the behavioral domain. These criteria provide a conceptual foundation for the study of novelty in behavioral traits. (shrink)

Understanding the evolutionary role of environmentally induced phenotypic variation (i.e., plasticity) is an important issue in developmental evolution. A major physiological response to environmental change is cellular stress, which is counteracted by generic stress reactions detoxifying the cell. A model, stress‐induced evolutionary innovation (SIEI), whereby ancestral stress reactions and their corresponding pathways can be transformed into novel structural components of body plans, such as new cell types, is described. Previous findings suggest that the cell differentiation cascade of a (...) cell type critical to pregnancy in humans, the decidual stromal cell, evolved from a cellular stress reaction. It is hypothesized that the stress reaction in these cells was elicited ancestrally via inflammation caused by embryo attachment. The present study proposes that SIEI is a distinct form of plasticity‐based evolutionary change leading to the origin of novel structures rather than adaptive transformation of pre‐existing characters. (shrink)

Two embryonic tissues—the neural crest and the cranial placodes—give rise to most evolutionary novelties of the vertebrate head. These two tissues develop similarly in several respects: they originate from ectoderm at the neural plate border, give rise to migratory cells and develop into multiple cell fates including sensory neurons. These similarities, and the joint appearance of both tissues in the vertebrate lineage, may point to a common evolutionary origin of neural crest and placodes from a specialized population of (...) neural plate border cells. However, a review of the developmental mechanisms underlying the induction, specification, migration and cytodifferentiation of neural crest and placodes reveals fundamental differences between the tissues. Taken together with insights from recent studies in tunicates and amphioxus, this suggests that neural crest and placodes have an independent evolutionary origin and that they evolved from the neural and non‐neural side of the neural plate border, respectively. BioEssays 30:659–672, 2008. © 2008 Wiley Periodicals, Inc. (shrink)

In the 20th century, genetic explanatory approaches became dominant in both developmental and evolutionary biological research. By contrast, physical approaches, which appeal to properties such as mechanical forces, were largely relegated to the margins, despite important advances in modeling. Recently, there have been renewed attempts to find balanced viewpoints that integrate both biological physics and molecular genetics into explanations of developmental and evolutionary phenomena. Here we introduce the 2017 SICB symposium “Physical and Genetic Mechanisms for Evolutionary (...) class='Hi'>Novelty” that was dedicated to exploring empirical cases where both biological physics and developmental genetic considerations are crucial. To further contextualize these case studies, we offer two theoretical frameworks for integrating genetic and physical explanations: combining complementary perspectives and comprehensive unification. We conclude by arguing that intentional reflection on conceptual questions about investigation, explanation, and integration is critical to achieving significant empirical and theoretical advances in our understanding of how novel forms originate across the tree of life. (shrink)

Throughout the recent history of research at the intersection of evolution and development, notions such as developmental constraint, evolutionary novelty, and evolvability have been prominent, but the term ‘developmental bias’ has scarcely been used. And one may even doubt whether a unique and principled definition of bias is possible. I argue that the concept of developmental bias can still play a vital scientific role by means of setting an explanatory agenda that motivates investigation and guides the formulation of (...) integrative explanatory frameworks. Less crucial is a definition that would classify patterns of phenotypic variation and unify variational patterns involving different traits and taxa as all being ‘bias.’ Instead, what we should want is a concept that generates intellectual identity across various researchers, and that unites the diverse fields and approaches relevant to the study of developmental bias, from paleontology to behavioral biology. I point to some advantages of conducting research specifically under the label of ‘developmental bias,’ compared to employing other, more common terms such as ‘evolvability.’. (shrink)

Great promise for the evolutionary analysis of animal behavior lies in the distinction between generative novelties and the evolutionary innovations to which they can give rise. Ramsey et al. succeed in emphasizing the contribution of individual learning and intelligence to behavioral innovations, but do not correct the tendency to confound individual invention with socio-ecological or group-level innovation.

Research on surprise relevant to the cognitive-evolutionary model of surprise proposed by Meyer, Reisenzein, and Schützwohl is reviewed. The majority of the assumptions of the model are found empirically supported. Surprise is evoked by unexpected events and its intensity is determined by the degree if schema-discrepancy, whereas the novelty and the valence of the eliciting events probably do not have an independent effect. Unexpected events cause an automatic interruption of ongoing mental processes that is followed by an attentional (...) shift and attentional binding to the events, which is often followed by causal and other event analysis processes and by schema revision. The facial expression of surprise postulated by evolutionary emotion psychologists has been found to occur rarely in surprise, for as yet unknown reasons. A physiological orienting response marked by skin conductance increase, heart rate deceleration, and pupil dilation has been observed to occur regularly in the standard version of the repetition-change paradigm of surprise induction, but the specificity of these reactions as indicators of surprise is controversial. There is indirect evidence for the assumption that the feeling of surprise consists of the direct awareness of the schema-discrepancy signal, but this feeling, or at least the self-report of surprise, is also influenced by experienced interference. In contrast, facial feedback probably does contribute substantially to the feeling of surprise and the evidence for the hypothesis that surprise is affected by the difficulty of explaining an unexpected event is, in our view, inconclusive. Regardless of how the surprise feeling is constituted, there is evidence that it has both motivational and informational effects. Finally, the prediction failure implied by unexpected events sometimes causes a negative feeling, but there is no convincing evidence that this is always the case, and we argue that even if it were so, this would not be a sufficient reason for regarding this feeling as a component, rather than as an effect of surprise. (shrink)

Evolutionary genetics is concerned with natural selection and neutral drift, to the virtual exclusion of almost everything else. In its current focus on DNA variation, it reduces phenotypes to symbols. Varying phenotypes, however, are the units of evolution, and, if we want a comprehensive theory of evolution, we need to consider both the internal and external evolutionary forces that shape the development of phenotypes. Genetic systems are redundant, modular and subject to a variety of genomic mechanisms of “turnover” (...) (transposition, gene conversion, unequal crossingover, slippage and so on). As such the construction and spread of novel combinations of modules by turnover, in particular within gene promoters, contributes significantly to the evolution of phenotypes. Furthermore, redundancy, turnover and modularity lead to ever more complex networks of genetic interactions and ever more functions for a given module. The significant interaction between genomic turnover and natural selection leads to a molecular coevolution between interacting modules and hence facilitates the establishment of biological novelties. BioEssays 22:1153–1159, 2000. © 2000 John Wiley & Sons, Inc. (shrink)

In the context of macroevolutionary transitions, environmental changes prompted vertebrates already bearing genetic variations to undergo gradual adaptations resulting in profound anatomical, physiological, and behavioral adaptations. The emergence of new genes led to the genetic variation essential in metazoan evolution, just as was gene loss, both sources of genetic variation resulting in adaptive phenotypic diversity. In this context, F12‐coding protein with defense and hemostatic roles emerged some 425 Mya, and it might have contributed in aquatic vertebrates to the transition from (...) water‐to‐land. Conversely, the F12 loss in marine, air‐breathing mammals like cetaceans has been associated with phenotypic adaptations in some terrestrial mammals in their transition to aquatic lifestyle. More recently, the advent of technological innovations in western lifestyle with blood‐contacting devices and harmful environmental nanoparticles, has unfolded new roles of FXII. Environment operates as either a positive or a relaxed selective pressure on genes, and consequently genes are selected or lost. FXII, an old dog facing environmental novelties can learn new tricks and teach us new therapeutic avenues. (shrink)

David Hull's (1988c) model of science as a selection process suffers from a two-fold inability: (a) to ascertain when a lineage of theories has been established; i.e., when theories are descendants of older theories or are novelties, and what counts as a distinct lineage; and (b) to specify what the scientific analogue is of genotype and phenotype. This paper seeks to clarify these issues and to propose an abstract model of theories analogous to particulate genetic structure, in order to reconstruct (...) relationships of descent and identity. (shrink)

This paper takes a close look at the role of behavior in the “major transitions” in evolution—events during which inheritance and development, and therefore the process of adaptation by natural selection, are reorganized at a new level of compositional hierarchy—and at the requirements for sufficiently explaining these important events in the history of life. I argue that behavior played a crucial role in driving at least some of the major transitions. Because behavioral interactions can become stably organized in novel ways (...) on timescales faster than the lifetime of an organism, behavior can lead the way into a transition—becoming organized at the new level prior to inheritance and development. It is widely acknowledged that behavioral plasticity can play an important role in evolution; environmental novelty can elicit novel behavior that may feed back on the evolutionary process through niche selection or cultural inheritance, for example (Jablonka and Lamb 2005). I argue here that not just novel behaviors but novel forms of behavioral organization (distributed or hierarchical control that produces functional coherence) can emerge, binding the evolutionary fates of a group of organisms which were previously independent in terms of behavior as well as reproduction, and leading the way into a transition to an aggregative or “higher-level” mode of reproduction. (shrink)

Early 20th century philosopher Henri Bergson posited an initial push that propelled the diversity of life forward into a varied, novel future: The élan vital, a necessary force or impulse that animated life’s progress and development. His idea had largely been abandoned by mid-century. Even so, much of the conceptual and explanatory work this impulse targeted is yet in want of an explanation. In particular, Bergson’s derelict ideas on evolution addressed three areas that have once again become relevant in the (...) effort to unite evolutionary genetics, biological development, and ecological context : the purposeful nature of individual organisms and their parts; the integrative, holistic, non-linear emergent dynamics seen in evolutionary processes; and how genuine novelty emerges into the universe :422, 2016; Simondon et al. in On the mode of existence of technical objects. Univocal series, Univocal Publishing LLC, Minneapolis, 2017; Bang, in: Winther-Lindqvist, Bang, Valsiner Nothingness: philosophical insights into psychology, Transaction Publishers, Somerset, 2016; Moreno and Mossio in Biological autonomy: a philosophical and theoretical enquiry. History, philosophy and theory of the life sciences, Springer, Dordrecht, 2015). In this paper I argue that Bergson’s ideas may yet be relevant to these questions, and his work warrants a reexamination in light of current problems in evolutionary biology. This is not a call to ‘return’ to Bergson, nevertheless his notions about complexity suggest ways of looking at current biological problems in ways that offer a heuristic insight worth entertaining. Bergson’s Nobel Prize-winning book, Creative Evolution, provided a strikingly prescient early 20th century framework for understanding how Darwinian evolution acts as an engine for generating new forms, University Press of America, Lanham, Bergson 1911). (shrink)