What kind mechanisms one deems central for the evolutionary process deeply influences one's understanding of the nature of organisms, including cognition. Reversely, adopting a certain approach to the nature of life and cognition and the relationship between them or between the organism and its environment should affect one's view of evolutionary theory. This paper explores this reciprocal relationship in more detail. In particular it argues that the view of living and cognitive systems, especially humans, as deeply integrated beings embedded in (...) and transformed by their genetic, epigenetic, behavioral, ecological, socio-cultural and cognitive-symbolic legacies calls for an extended evolutionary synthesis that goes beyond either a theory of genes juxtaposed against a theory of cultural evolution and or even more sophisticated theories of gene-culture coevolution and niche construction. Environments, particularly in the form of developmental environments, do not just select for variation, they also create new variation by influencing development through the reliable transmission of non-genetic but heritable information. This paper stresses particularly views of embodied, embedded, enacted and extended cognition, and their relationship to those aspects of extended inheritance that lie between genetic and cultural inheritance, the still gray area of epigenetic and behavioral inheritance systems that play a role in parental effect. These are the processes that can be regarded as transgenerational developmental plasticity and that I think can most fruitfully contribute to, and be investigated by, developmental psychology. (shrink)

Everyone has heard of ‘epigenetics’, but the term means different things to different researchers. Four important contemporary meanings are outlined in this paper. Epigenetics in its various senses has implications for development, heredity, and evolution, and also for medicine. Concerning development, it cements the vision of a reactive genome strongly coupled to its environment. Concerning heredity, both narrowly epigenetic and broader ‘exogenetic’ systems of inheritance play important roles in the construction of phenotypes. A thoroughly epigenetic model of development and evolution (...) was Waddington’s aim when he introduced the term ‘epigenetics’ in the 1940s, but it has taken the modern development of molecular epigenetics to realize this aim. In the final sections of the paper we briefly outline some further implications of epigenetics for medicine and for the nature/nurture debate. (shrink)

The concept of biological inheritance has recently been extended so as to integrate, among other elements, parts of organisms’ environments. The literature refers to the trans-generational reconstruction of these parts in terms of environmental or ecological inheritance. This article’s main objective is to clarify the different meanings of "environmental inheritance," to underline so far unnoticed theoretical difficulties associated to this polysemous notion and to consequently argue that inheritance, even when extended, should be theoretically distinguished from trans-generational environmental stability. After disentangling (...) the different meanings of environmental inheritance, I underline that studies dealing with this concept place themselves in the wake of earlier contributions about biological environment and elaborate on the role of organisms in the determination of their relevant developmental and selective surroundings. This leads me to question the legitimacy of the category shift operated by niche inheritance proponents—from environment to inheritance—and to explain why the very concept of inherited environment shows important and so far unnoticed theoretical limitations. In this context, I assert the necessity to distinguish two related but different research programs: the construction of a finer-grained theory of environment and the elaboration of an extended theory of inheritance. (shrink)

The concept of biological inheritance has recently been extended so as to integrate, among other elements, parts of organisms’ environments. The literature refers to the trans-generational reconstruction of these parts in terms of environmental or ecological inheritance. This article’s main objective is to clarify the different meanings of "environmental inheritance," to underline so far unnoticed theoretical difficulties associated to this polysemous notion and to consequently argue that inheritance, even when extended, should be theoretically distinguished from trans-generational environmental stability. After disentangling (...) the different meanings of environmental inheritance, I underline that studies dealing with this concept place themselves in the wake of earlier contributions about biological environment and elaborate on the role of organisms in the determination of their relevant developmental and selective surroundings. This leads me to question the legitimacy of the category shift operated by niche inheritance proponents—from environment to inheritance—and to explain why the very concept of inherited environment shows important and so far unnoticed theoretical limitations. In this context, I assert the necessity to distinguish two related but different research programs: the construction of a finer-grained theory of environment and the elaboration of an extended theory of inheritance. (shrink)

In this paper, I analyze the disruptive impact of Darwinian selectionism for the century-long tradition in which the environment had a direct causative role in shaping an organism’s traits. In the case of humans, the surrounding environment often determined not only the physical, but also the mental and moral features of individuals and whole populations. With its apparatus of indirect effects, random variations, and a much less harmonious view of nature and adaptation, Darwinian selectionism severed the deep imbrication of organism (...) and milieu posited by these traditional environmentalist models. This move had radical implications well beyond strictly biological debates. In my essay, I discuss the problematization of the moral idiom of environmentalism by William James and August Weismann who adopted a selectionist view of the development of mental faculties. These debates show the complex moral discourse associated with the environmentalist-selectionist dilemma. They also well illustrate how the moral reverberations of selectionism went well beyond the stereotyped associations with biological fatalism or passivity of the organism. Rereading them today may be helpful as a genealogical guide to the complex ethical quandaries unfolding in the current postgenomic scenario in which a revival of new environmentalist themes is taking place. (shrink)

Advocates of an ‘extended evolutionary synthesis’ have claimed that standard evolutionary theory fails to accommodate epigenetic inheritance. The opponents of the extended synthesis argue that the evidence for epigenetic inheritance causing adaptive evolution in nature is insufficient. We suggest that the ambiguity surrounding the conception of the gene represents a background semantic issue in the debate. Starting from Haig’s gene-selectionist framework and Griffiths and Neumann-Held’s notion of the evolutionary gene, we define senses of ‘gene’, ‘environment’, and ‘phenotype’ in a way (...) that makes them consistent with gene-centric evolutionary theory. We argue that the evolutionary gene, when being materialized, need not be restricted to nucleic acids but can encompass other heritable units such as epialleles. If the evolutionary gene is understood more broadly, and the notions of environment and phenotype are defined accordingly, current evolutionary theory does not require a major conceptual change in order to incorporate the mechanisms of epigenetic inheritance. _1_ Introduction _2_ The Gene-centric Evolutionary Theory and the ‘Evolutionary Gene’ _2.1_ The evolutionary gene _2.2_ Genes, phenotypes, and environments _3_ Epigenetic Inheritance and the Gene-Centred Framework _3.1_ Treating the gene as the sole heritable material? _3.2_ Epigenetics and phenotypic plasticity _4_ Conclusion. (shrink)

This article is arranged around two general claims and a thought experiment. I begin by suggesting that the genome should be studied as a developmental system, and that genes supervene on genomes (rather than the other way around). I move on to present a thought experiment that illustrates the implications a dynamic view of the genome has for central concepts in biology, in particular the information content of the genome, and the notion of responses to stress.

The “Encyclopedia of DNA Elements” (ENCODE) project was launched by the US National Human Genome Research Institute in the aftermath of the Human Genome Project (HGP). It aimed to systematically map the human transcriptome, and held the promise that identifying potential regulatory regions and transcription factor binding sites would help address some of the perplexing results of the HGP. Its initial results published in 2012 produced a flurry of high-impact publications as well as criticisms. Here we put the results of (...) ENCODE and the work on epigenomics that followed in a broad theoretical and historical context, focusing on three strands of research. The first is the history of thinking about the organization of genomes, both physical and regulatory. The second is the history of ideas about gene regulation, primarily in eukaryotes. Finally, and connecting these two issues, we suggest how to think about the role of genetic material in physiology and development. (shrink)

In his target article, Koonin discusses the insights into the evolution of bacterial genomes provided by the CRISPR-Cas system. This evolved defense system is based on intrinsic processes of genome engineering which, as he argues, enable Lamarckian inheritance. In this commentary I discuss some historical and conceptual issues that pertain to Koonin’s analysis of this aspect of the CRISPR-Cas system, extending and qualifying his discussion.

Many natural and biological phenomena can be depicted as networks. Theoretical and empirical analyses of networks have become prevalent. I discuss theoretical biases involved in the delineation of biological networks. The network perspective is shown to dissolve the distinction between regulatory architecture and regulatory state, consistent with the theoretical impossibility of distinguishing a priori between “program” and “data”. The evolutionary significance of the dynamics of trans-generational and inter-organism regulatory networks is explored and implications are presented for understanding the evolution of (...) the biological categories development-heredity; plasticity-evolvability; and epigenetic-genetic. (shrink)