Understanding variation beyond the Modern Synthesis

In 2013 Emanuele Serrelli organized the session “Understanding variation beyond the Modern Synthesis” at the International Society for the History, Philosophy, and Social Studies of Biology Sunday, 7-11 July, Montpellier, France. The session, supported by AppEEL, includes Pablo Razeto-Barry and Davide Vecchi (Instituto de Filosofía y Ciencias de la Complejidad, Santiago, Chile) and Nathalie Gontier (University of Lisbon).

Emanuele’s paper:

Serrelli E (2013). Phenotypic variation in ecological setting: a challenge for evolutionary modeling beyond the Modern Synthesis. Meeting of the International Society for History, Philosophy, and Social Studies of Biology (ISHPSSB), Montpellier, France, July 7-11. [BOA] [Ac]

Other talks in the session:

Variation in a world with multiple levels, mechanisms, and units of evolution: The Applied Evolutionary Epistemology Approach
Nathalie Gontier

Scholars working within the units and levels of selection debate have been developing more and more refined heuristics of how evolution by means of natural selection works. A motivation of such endeavor has been the question whether individual organisms are the only, or the most appropriate, units of natural selection, or whether groups, traits, a (set of) genes or behaviors, developmental systems, population, species can also be considered as units of selection. Heuristics based on natural selection have also been applied in order to assess whether evolution by natural selection can occur within phenomena that are traditionally understood to be extra-biological, such as cultural units, artifacts, neural maps, cognitive traits, altruistic rules etc. This abstraction and extension of natural selection to the sociocultural domain, provides a unified scientific methodology that enables scholars to study the evolution of life as well as the evolution of cognition, science, culture and any other phenomenon displayed by living organisms by means of natural selection theory. Today, with the several pleas there exist to extend the Modern Synthesis, evolutionary biologists are acknowledging the importance of mechanisms such as lateral gene transfer, symbiogenesis, drift, etc. Applied Evolutionary epistemology is a methodology that provides more open heuristics to assess how these mechanisms associated with an extended synthesis work, what their units and levels, and where they are active. Associated with this endavour is not only the recognition of multiple units, levels and mechanisms of evolution, but also to acknowledgement that there are different kinds of evolution (the evolution of the brain, of languages, of culture, of niches, etc). This talk takes the debate a step further, asking how important inter-unit, inter-level and inter-mechanism variation is for a general understanding of evolution.

Mutational Lamarckism and the Modern Synthesis view of mutational randomness as conditional independence
Pablo Razeto-Barry and Davide Vecchi
Current evolutionary biology is based on the legacy of the modern evolutionary synthesis (Huxley 1942). Nevertheless, the Modern Synthesis enshrined natural selection as the director of adaptive evolution not by providing evidence that it did, or could, account for observed adaptations (Leigh 1999), but rather by eliminating competing explanations (Mayr 1993). One of the eliminated competitors was Lamarckism, particularly “mutational Lamarckism”, a hypothesis according to which mutations may be directed towards producing phenotypes that improve the performance of the organism in a particular environment. Contrary to this hypothesis, the Modern Synthesis’ view claims that mutations are “random” (Lenski and Mittler 1993, Merlin 2010). Possibly because Lamarckism had largely felt into disrepute several decades before the eventual success of the Modern Synthesis, the precise meaning of the term “random mutation” was never deeply analyzed. However, current evidence of possibly legitimate cases of Lamarckism (Jablonka and Lamb 2005, Koonin and Wolf 2009) has revitalized the interest for clarifying the meaning of the term “random” in this context (Sarkar 2007, Jablonka and Lamb 2005, Millstein 1997, Merlin 2010). In this contribution we aim to analyze previous definitions of random mutations based on the concepts of statistical independence and correlation (e.g., Millstein 1997, Sarkar 2005, Jablonka and Lamb, Merlin 2010) and to show that they are deficient. We argue that the term “random mutation” refers to a triadic rather than dyadic relationship, that neither correlation nor independence are good concepts to formalize the neo-Darwinian concept of genetic randomness, and that as a consequence neither of them is suitable to define mutational Lamarckism. In this contribution we will illustrate our alternative proposal, show a way to formalize the concept of mutational randomness and provide some examples of its application.