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

In a now classic paper published in 1991, Alberch introduced the concept of genotype–phenotype (G!P) mapping to provide a framework for a more sophisticated discussion of the integration between genetics and developmental biology that was then available. The advent of evo-devo first and of the genomic era later would seem to have superseded talk of transitions in phenotypic space and the like, central to Alberch’s approach. On the contrary, this paper shows that recent empirical and theoretical advances have only sharpened (...) the need for a different conceptual treat- ment of how phenotypes are produced. Old-fashioned metaphors like genetic blueprint and genetic programme are not only woefully inadequate but positively misleading about the nature of G!P, and are being replaced by an algorithmic approach emerging from the study of a variety of actual G!P maps. These include RNA folding, protein function and the study of evolvable soft- ware. Some generalities are emerging from these disparate fields of analysis, and I suggest that the concept of ‘developmental encoding’ (as opposed to the classical one of genetic encoding) provides a promising computational–theoretical underpinning to coherently integrate ideas on evolvability, modularity and robustness and foster a fruitful framing of the G!P mapping problem. (shrink)

Biological evolution is often viewed narrowly as a change of morphology or allele frequency in a sequence of generations. Here I pursue an alternative informational concept of evolution, as preservation, advance, and emergence of functional information in natural agents. Functional information is a network of signs that are used by agents to preserve and regulate their functions. Functional information is preserved in evolution via complex interplay of copying and construction processes: the digital components are copied, whereas interpreting subagents together with (...) scaffolds, tools, and resources, are constructed. Some of these processes are simple and invariant, whereas others are complex and contextual. Advance of functional information includes improvement and modification of already existing functions. Although the genome information may change passively and randomly, the interpretation is active and guided by the logic of agent behavior and embryonic development. Emergence of new functions is based on the reinterpretation of already existing information, when old tools, resources, and control algorithms are adopted for novel functions. Evolution of functional information progressed from protosemiosis, where signs correspond directly to actions, to eusemiosis, where agents associate signs with objects. Language is the most advanced form of eusemiosis, where the knowledge of objects and models is communicated between agents. (shrink)

Adaptation by means of natural selection depends on the ability of populations to maintain variation in heritable traits. According to the Modern Synthesis this variation is sustained by mutations and genetic drift. Epigenetics, evodevo, niche construction and cultural factors have more recently been shown to contribute to heritable variation, however, leading an increasing number of biologists to call for an extended view of speciation and evolution. An additional common feature across the animal kingdom is learning, defined as the ability to (...) change behavior according to novel experiences or skills. Learning constitutes an additional source for phenotypic variation, and change in behavior may induce long lasting shifts in fitness, and hence favor evolutionary novelties. Based on published studies, I demonstrate how learning about food, mate choice and habitats has contributed substantially to speciation in the canonical story of Darwin’s finches on the Galapagos Islands. Learning cannot be reduced to genetics, because it demands decisions, which requires a subject. Evolutionary novelties may hence emerge both from shifts in allelic frequencies and from shifts in learned, subject driven behavior. The existence of two principally different sources of variation also prevents the Modern Synthesis from self-referring explanations. (shrink)

Cet ouvrage, un grand classique désormais, son auteur l'a écrit pour répondre au "devoir qui s'impose, aujourd'hui plus que jamais, aux hommes de science de penser leur discipline dans l'ensemble de la culture moderne pour l'enrichir non seulement de connaissances techniquement importantes, mais aussi des idées venues de leur science qu'ils peuvent croire humainement signifiantes. L ingénuité même d'un regard neuf (celui de la science l'est toujours) peut parfois éclairer d'un jour nouveau d'anciens problèmes...".

The individual and social formation of a human self, from its emergence in early childhood through adolescence to adult life, has been described within philosophy, psychology and sociology as a product of developmental and social processes mediating a linguistic and social world. Semiotic scaffolding is a multi-level phenomenon. Focusing upon levels of semiosis specific to humans, the formation of the personal self and the role of friendship and similar interpersonal relations in this process is explored through Aristotle’s classical idea of (...) the friend as ‘another self’, and sociologist Margaret Archer’s empirical and theoretical work on the interplay between individual subjectivity, social structure and interpersonal relations in a dynamics of human agency. It is shown that although processes of reflexivity and friendship can indeed be seen as instances of semiotic scaffolding of the emerging self, such processes are heterogeneous and contingent upon different modes of reflexivity. (shrink)

We discuss the difference between formal and natural languages, and argue that should the language metaphor have any foundation, it’s analogy with natural languages that should be taken into account. We discuss how such operation like reading, writing, sign, interpretation, etc., can be applied in the realm of the living and what can be gained, by such an approach, in order to understand the phenomenon of life.

We develop here a semiotic model of evolution. We point out the role of confusion and choice as a condition for semiosis, which is a precondition for semiotic learning and semiotic adaptation. Semiosis itself as interpretation and decision-making between options requires phenomenal present. The body structure of the organism is largely a product of former semiosis. The organism’s body together with the structure of the ecosystem serves also as a scaffolding for the sign processes that carry on the ontogenetic cycle (...) and the organisms’ behaviour, providing the experience-based channels for decision making in the indeterminate situations of choice. The stability and persistence of ontogenesis and behaviour are based on the plasticity, or the multiviality of organic dynamics. The same plasticity or multivial dynamics is providing the material for further potential evolution. Evolution has occurred when some change becomes irreversible via its stabilization, and it usually means a modification of existing constraints, or scaffoldings. Some examples of these processes are described in the article. (shrink)

"Eco wittily and enchantingly develops themes often touched on in his previous works, but he delves deeper into their complex nature... this collection can be read with pleasure by those unversed in semiotic theory." —Times Literary Supplement.

The discovery of the genetic code has shown that the origin of life has also been the origin of semiosis, and the discovery of many other organic codes has indicated that organic semiosis has been the sole form of semiosis present on Earth in the first three thousand million years of evolution. With the origin of animals and the evolution of the brain, however, a new type of semiosis came into existence, a semiosis that is based on interpretation and is (...) commonly referred to as interpretive, or Peircean semiosis. This suggests that there are two distinct types of semiosis in Nature, one based on coding and one based on interpretation, and all the experimental evidence that we have does support this conclusion. Both in principle and in practice, therefore, there is no conflict between organic semiosis and Peircean semiosis, and yet they have been the object of a fierce controversy because it has been claimed that semiosis is always based on interpretation, even at the cellular level. Such a claim has recently been reproposed in a number of papers and it has become necessary therefore to reexamine it in the light of the proposed arguments. (shrink)