Giorgio Airoldi

The assumption that natural selection alone is sufficient to explain not only which traits get fixed in a population/species, but also how they develop, has been questioned since Darwin’s times, and increasingly in the last decades. Alternative theories, linked to genetic and phenotypic processes, or to the theory of complex systems, have been proposed to explain the rise of the phenotypic variety upon which natural selection acts. In this article, we illustrate the current state of the issue and we propose a logical space based on phenotypic robustness that allows a classification of evolutionary phenomena and can provide a framework for unifying all these accounts.

Abstractabstract:Public health emergencies are fraught by epistemic uncertainty, which raises policy issues of how to handle that uncertainty and devise sustainable public health responses. Among such responses, a herd immunity policy might be an option. Particularly before the development of vaccines, the current COVID-19 pandemic has highlighted the polarized nature of the political debate concerning the ethical feasibility of herd immunity strategies. This article provides a conceptual framework tailored to uncover the ethical rationale behind such strategies. Clarity on this issue is important in order to facilitate the terms of the political debate when tackling future health emergencies.

Los conceptos de evolución y cambio evolutivo son a la vez laxos y polisémicos: se aplican a fenómenos muy diferentes y no siempre se definen con precisión. La aplicación extendida del paradigma neo-darwinista clásico, además, suele imponer un esquema adaptacionista al análisis de los hechos evolutivos, en el cual las funciones juegan un papel lógicamente anterior a los rasgos y sus formas. En este artículo proponemos, como etapa previa a la formulación de hipótesis sobre las causas del cambio, un modelo de espacio forma-función que pueda responder a preguntas como cuándo se da un cambio en los rasgos de una arquitectura biológica y de qué tipo son estos cambios. Un modelo de este tipo nos permite ver claramente cuándo se da un cambio en la forma o en la función y qué alcance evolutivo tiene.

The COVID-19 pandemic poses extraordinary public health challenges. In order to respond to such challenges, most democracies have relied on so-called ‘evidence-based’ policies, which supposedly devolve to science the burden of their justification. However, the biomedical sciences can only provide a theory-laden evidential basis, while reliable statistical data for policy support is often scarce. Therefore, scientific evidence alone cannot legitimise COVID-19 public health policies, which are ultimately based on political decisions. Given this inevitable input on policy-making, the risk of arbitrariness is ubiquitous and democratic scrutiny becomes essential to counter it. During the COVID-19 pandemic, the standards of scientific and democratic scrutiny have been, as a matter of fact, substantially lowered. This erosion potentially damages democracy.

Discussions about the extended mind have ‘extended’ in various directions in the last decades. While applied to other aspects of human cognition and even consciousness, the extended-mind hypothesis has also been criticized, as it questions fundamental ideas such as the image of a dual world, divided between an external and an internal domain by the border of ‘skin and skull’, the idea of a localized and constant decision center, and the role of internal representations. We suggest that the main virtue of the hypothesis is not as a theory per se, but as a vaccine against persistent metaphysical prejudices about the mind’s structure, functions and borders. Being an hypothesis about the most efficient ways to combine resources and problems, and not a theory about the mind’s a-priori constitution, the extended mind view moves the focus from ontology to pragmatics and helps purify philosophy of mind from metaphysical remainders.

The assumption that natural selection alone is sufficient to explain not only which traits get fixed in a population/species, but also how they develop, has been questioned since Darwin’s times, and increasingly in the last decades. Alternative theories, linked to genetic and phenotypic processes, or to the theory of complex systems, have been proposed to explain the rise of the phenotypic variety upon which natural selection acts. In this article, we illustrate the current state of the issue and we propose a logical space based on phenotypic robustness that allows a classification of evolutionary phenomena and can provide a framework for unifying all these accounts.

El proyecto del ‘Darwinismo Formal’ de Alan Grafen propone una formulación matemática de la teoría de Darwin que pretende demostrar que la selección natural moldea los rasgos fenotípicos a través de la maximización de la eficacia. El proyecto de Grafen reposa sobre tres premisas: la selección natural es la única fuerza que moldea los fenotipos; la eficacia es la única medida de le evolución; y el diseño biológico surge como resultado de un proceso de optimización selectiva. En este trabajo argumentamos que estas tres premisas limitan la aplicabilidad del modelo a los hechos evolutivos más simples. Esto se debe a que Grafen implícitamente presupone un concepto de eficacia que es a la vez causa y efecto de las novedades fenotípicas; lo que, por un lado, vacía la teoría de Darwin de poder explicativo y, por el otro, lleva a ignorar la potencial contribución de fuerzas evolutivas no selectivas en la configuración de la complejidad biológica. Para superar estos escollos del proyecto de del Darwinismo Formal - que son además comunes a todos los modelos formales adaptacionistas - proponemos sustituir el concepto causal de eficacia por el de robustez, definiendo así el diseño biológico como forma y función en lugar de como maximización de la eficacia.

Darwin’s claim that Natural Selection, through optimization of fitness, explains complex biological design has not yet been properly formalized. Alan Grafen’s Formal Darwinism Project aims at providing such a formalization and at demonstrating that fitness maximization is coherent with results from Population Genetics, usually interpreted as denying it. We suggest that Grafen’s proposal suffers from some limitations linked to its concept of design as optimized fitness. In order to overcome these limitations, we propose a classification of evolutionary facts based on a bi-dimensional complexity space, which adds robustness to fitness as measure of the quality of a design. In this space, each point represents an organismic architecture, and movement between two points would be an evolutionary fact. Natural Selection explains movement along the fitness axis, while non-selective mechanisms explain movement on the robustness axis. Moreover, we propose a thermodynamic metaphor to draw parallelisms between notions of fitness and entropy, robustness and energy, and movement in this space and reversible and irreversible cycles. We argue that this metaphor illustrates different evolutionary processes usually overlooked by proposals of formalization of Darwinian theory, such Grafen’s Formal Darwinism Project.