I am a theoretical biologist working at the crossroads of experimental biology, mathematics, and philosophy. I also work on the Anthropocene, among many other interests.
What understanding does the closure of constraints bring about a biological system in practices? Without discussing particular cases, one cannot answer this question. The goal of this workshop is to bring together and synthesize individual modeling experiences in physiology and ecology to establish perspectives of research collectively regarding organization in biology, sensu closure of constraints. This workshop is intended to a specialized audience. We encourage speakers to present models or modeling methods, and share critical reflections on their work and the difficulties encountered. Identifying achievements, open questions, perspectives, and experimental, conceptual or technical difficulties is the main goal of this meeting. Additionally to relatively short Q&A sessions, a general discussion will synthesize the main points raised during the day. This synthesis will be transcribed and shared with the participants after the workshop.
En biologie, le hasard est une notion essentielle pour comprendre les variations ; cependant, cette notion n'est généralement pas conceptualisée avec précision. Nous apportons ici quelques éléments allant dans ce sens.
Abstract
La physique possède plusieurs concepts de hasard qui reposent néanmoins tous sur l’idée que les possibilités sont données d’avance. En revanche, un nombre croissant de biologistes théoriciens cherchent à introduire la notion de nouvelles possibilités, c’est-à-dire des modifications de l’espace des possibles - une idée déjà discutée par Bergson et qui n’a pas été véritablement poursuivie scientifiquement jusqu’à récemment (sauf, en un sens, dans la systématique, c’est-à-dire la méthode de classification des êtres vivants). <br> Alors, le hasard opère au niveau des possibilités elles-mêmes et est à la base de l’historicité des objets biologiques. Nous soulignons que ce concept de hasard n’est pas seulement pertinent lorsqu’on cherche à prédire l’avenir. Au contraire, il façonne les organisations biologiques et les écosystèmes. À titre d’illustration, nous soutenons qu’une question cruciale de l’Anthropocène est la disruption des organisations biologiques que l’histoire naturelle a structurées, conduisant à un effondrement des possibilités biologiques.
Citation
Montévil, Maël. n.d. “Comment Le Hasard Façonne Le Vivant ?” In Figures Du Hasard, edited by Anne Duprat, Fiona Mcintosh-Varjabédian, Anne-Gaëlle Weber, Alison James, and Divya Dwivedi. CNRS éditions
In biology, randomness is a critical notion to understand variations; however this notion is typically not conceptualized precisely. Here we provide some elements in that direction.
Abstract
Physics has several concepts of randomness that build on the idea that the possibilities are pre-given. By contrast, an increasing number of theoretical biologists attempt to introduce new possibilities, that is to say, changes of possibility space – an idea already discussed by Bergson and that was not genuinely pursued scientifically until recently (except, in a sense, in systematics, i.e, the method to classify living beings). <br> Then, randomness operates at the level of possibilities themselves and is the basis of the historicity of biological objects. We emphasize that this concept of randomness is not only relevant when aiming to predict the future. Instead, it shapes biological organizations and ecosystems. As an illustration, we argue that a critical issue of the Anthropocene is the disruption of the biological organizations that natural history has shaped, leading to a collapse of biological possibilities.
Citation
Montévil, Maël. 2025. “How Does Randomness Shape the Living?” In Figures of Chance II Chance in Theory and Practice, edited by Anne Duprat, Alison James, and Divya Dwivedi. Taylor & Francis
Below is a podcast and transcript of the interview concerning the 1st chapter of the book Bifurquer
Abstract
Endocrine disruptors alter mammary gland development, impair the ability to nourish offspring, and increase the cancer risk in animal models. Epidemiological studies reveal trends towards early mammary development, nursing problems, and breast cancer in younger women. Morphological changes in mouse postnatal mammary gland development are considered sensitive markers of endocrine disruption. While the mouse mammary gland is easily amenable to morphometric measurements from the fetal stage to full maturity, the rat mammary gland grows more conspicuously into the third dimension, hindering conventional morphometric analysis. However, since rats are more commonly used in international toxicological reproductive studies, it would be beneficial to include mammary gland whole-mount analysis in these studies. Using our quantitative software to perform computer-driven analysis of the rat mammary epithelium we examined the effects of gestational and postnatal exposure to ketoconazole, an antifungal medication that affects steroidogenesis, and to the estrogen diethylstilbestrol in the mammary glands of 6- and 22-day-old females. Both treatments produced effects at both ages; the epithelium was smaller and less complex in exposed animals compared to controls. Global analysis with the permutation test showed that morphological evaluation of the PND22 mammary gland is sensitive to endocrine disruption and possibly non-monotonic. In addition to revealing that ketoconazole altered the mammary gland structure, these results suggest that for future toxicology studies, day 22 (at weaning) is more suitable than day 6 because it showed significant measurements and trends. If the collection of mammary glands is added to existing international test methods, PND22 could be a relevant time point.
We characterize biological organization as a closure of constraints, where constraints are defined at a given time scale and are interdependent.
Abstract
We propose a conceptual and formal characterisation of biological organisation as a closure of constraints. We first establish a distinction between two causal regimes at work in biological systems: processes, which refer to the whole set of changes occurring in non-equilibrium open thermodynamic conditions; and constraints, those entities which, while acting upon the processes, exhibit some form of conservation (symmetry) at the relevant time scales. We then argue that, in biological systems, constraints realise closure, i.e. mutual dependence such that they both depend on and contribute to maintaining each other. With this characterisation in hand, we discuss how organisational closure can provide an operational tool for marking the boundaries between interacting biological systems. We conclude by focusing on the original conception of the relationship between stability and variation which emerges from this framework.
Keywords: Biological organisation, Closure, Constraints, Symmetries, Time scales
Entropy is a transversal notion to understand the Anthropocene, from physics to biology and social organizations. For the living, it requires a counterpart: anti-entropy.
Abstract
The Anthropocene crisis is frequently described as the rarefaction of resources or resources per capita. However, both energy and minerals correspond to fundamentally conserved quantities from the perspective of physics. A specific concept is required to understand the rarefaction of available resources. This concept, entropy, pertains to energy and matter configurations and not just to their sheer amount. However, the physics concept of entropy is insufficient to understand biological and social organizations. Biological phenomena display both historicity and systemic properties. A biological organization, the ability of a specific living being to last over time, results from history, expresses itself by systemic properties, and may require generating novelties The concept of anti-entropy stems from the combination of these features. We propose that Anthropocene changes disrupt biological organizations by randomizing them, that is, decreasing anti-entropy. Moreover, second-order disruptions correspond to the decline of the ability to produce functional novelties, that is, to produce anti-entropy.
The evolution of life marks the end of a physics world view of law entailed dynamics. We discuss the notions of causation and of enablement.
Abstract
Biological evolution is a complex blend of ever changing structural stability, variability and emergence of new phe- notypes, niches, ecosystems. We wish to argue that the evo- lution of life marks the end of a physics world view of law entailed dynamics. Our considerations depend upon dis- cussing the variability of the very ”contexts of life”: the in- teractions between organisms, biological niches and ecosys- tems. These are ever changing, intrinsically indeterminate and even unprestatable: we do not know ahead of time the ”niches” which constitute the boundary conditions on selec- tion. More generally, by the mathematical unprestatability of the ”phase space” (space of possibilities), no laws of mo- tion can be formulated for evolution. We call this radical emergence, from life to life. The purpose of this paper is the integration of variation and diversity in a sound concep- tual frame and situate unpredictability at a novel theoretical level, that of the very phase space. Our argument will be carried on in close comparisons with physics and the mathematical constructions of phase spaces in that discipline. The role of (theoretical) symmetries as invariant preserving transformations will allow us to under- stand the nature of physical phase spaces and to stress the differences required for a sound biological theoretizing. In this frame, we discuss the novel notion of ”enablement”. Life lives in a web of enablement and radical emergence. This will restrict causal analyses to differential cases (a difference that causes a difference). Mutations or other causal differ- ences will allow us to stress that ”non conservation princi- ples” are at the core of evolution, in contrast to physical dynamics, largely based on conservation principles as sym- metries. Critical transitions, the main locus of symmetry changes in physics, will be discussed, and lead to ”extended criticality” as a conceptual frame for a better understanding of the living state of matter.
Les notions de production et d’industrie ont, contre leurs origines historiques, été confinées dans les deux derniers siècles à ce que l’on appelle le secteur secondaire, le secteur primaire étant, lui, dévolu à la matière dite première et qui regroupe pelle-mêle l’exploitation du vivant sauvage et domestique ainsi que l’extraction minière. Pourtant les fourmis sont bien – plus ou moins – industrieuses, le concept de reproduction est l’un des plus fondamental en biologie et même les processus physiques irréversibles produisent de l’entropie. Le passage à l'échelle de ces différents types de production est néanmoins distinct - et cette question est centrale pour l'industrie. Alors que le champs et les acteurs de l’industrie se reconfigurent tant pour des raisons technologiques « qu’écologiques », il nous semble pertinent de repenser ce que signifie produire à l’aune tant de la physique que de la biologie et de la technologie.
« Nous pouvons jeter les chiffres dans les plus grandes grappes de calcul que le monde ait jamais connues et laisser les algorithmes statistiques trouver des modèles là où la science ne le peut pas. La corrélation l'emporte sur la causalité, et la science peut progresser même sans modèles cohérents, sans théories unifiées... » Ces quelques mots, c’est le journaliste Chris Anderson qui les écrivait en 2008, il était alors rédacteur en chef du magazine américain Wired, son article faisait écho à l’essor des big data.
La biologie moléculaire a donné un cadre très fécond pour l’exploration empirique du vivant, mais ses résultats ont aussi et en même temps mis à mal son cadre conceptuel. Pour dépasser ce cadre, un certain nombre d’auteurs soulignent les défis théoriques que comporte la compréhension des êtres vivants dans leur historicité et organicité. Si l’on doit comprendre les êtres vivant comme des organisations biologiques, comment ne pas se perdre dans leur complexité ? Et si leurs régularités sont les résultat d’une histoire et continuent de changer, de produire une histoire, comment les objectiver ? Ces questions sont, nous le pensons, essentielles pour répondre aux défis de ce siècle concernant la santé et la biodiversité et croisent aussi la question de l’encadrement théorique de l’usage des nouvelles technologies dans le travail scientifique. Dans ce contexte, nous inaugurons ici le programme interdisciplinaire : fondations théoriques de la biologie. Notre approche consiste à aborder les questions théoriques en s’appuyant sur la philosophie, notamment l’épistémologie ainsi que la comparaison avec les innovations mais aussi les contraintes théoriques d’autres disciplines, notamment la physique. En s’appuyant sur cette réflexivité, il s’agira à la fois de réinterpréter les pratiques existantes et de développer de nouvelles pratiques et méthodes.
L’Association des Amis de la Génération Thunberg-Ars Industrialis (AAGT-AI) a comme objectif de nouer un dialogue intergénérationnel entre le monde académique au sens large et les mouvements de la jeunesse mobilisés face à la catastrophe écologique.
Il ne s’agira pas d’une démocratie mondiale, car il faut que les peuples se composent et se disposent.Mais nous affirmerons une essence démocratique du monde : peuplé par tous les vivants et par tous les parlants, tout entier configuré par leurs existences et par leurs paroles.
Nous sommes un groupe de mathématiciens qui dénonçons une mathématisation du monde orientée vers le contrôle, le quantitatif et le réductionnisme plutôt que vers l’invention et la construction de compréhensions.
PWD 