The Whole is Always Smaller Than Its Parts’. A Digital Test of Gabriel Tarde’s monads

In this paper we argue that the new availability of digital data sets allows one to revisit Gabriel Tarde’s (1843-1904) social theory that entirely dispensed with using notions such as individual or society. Our argument is that when it was impossible, cumbersome or simply slow to assemble and to navigate through the masses of information on particular items, it made sense to treat data about social connections by defining two levels: one for the element, the other for the aggregates. But once we have the experience of following individuals through their connections (which is often the case with profiles) it might be more rewarding to begin navigating datasets without making the distinction between the level of individual component and that of aggregated structure. It becomes possible to give some credibility to Tarde’s strange notion of ‘monads’. We claim that it is just this sort of navigational practice that is now made possible by digitally available databases and that such a practice could modify social theory if we could visualize this new type of exploration in a coherent way.Cet article vise à démonter que la disponibilité récente de données numériques permet de revisiter la théorie sociale de Gabriel Tarde (1843-1904) qui se passe totalement de notions telles que l’individu ou la société. Notre analyse repose sur l’idée que, tant qu’il était impossible, difficile ou simplement fastidieux d’amasser et de consulter des quantités d’informations liées à des sujets précis, il était logique de traiter les données relatives aux liens sociaux en définissant deux niveaux : un pour l’élément individuel, l’autre pour l’agrégat collectif. Mais dès que l’on suit les individus par le biais de leurs relations (ce que l’on fait généralement dans le cas des profils) il serait plus avantageux de naviguer à travers les fichiers de données sans distinguer le niveau de l’élément individuel de celui de la structure collective. On peut alors accorder une certaine crédibilité à l’étrange notion de « monades » de Tarde. Nous affirmons que c’est justement ce mode de navigation, rendu possible par l’accès aux bases de données numériques, qui permet de modifier la théorie sociologique. Au sens strict du terme, nous ne devrions plus parler de phénomènes collectifs par opposition à des phénomènes individuels, mais seulement d’autant de façons différentes de collecter des phénomènes.British Journal of Sociology Prize 2014

Modern termites inherited the potential of collective construction from their common ancestor

Animal collective behaviors give rise to various spatial patterns, such as the nests of social insects. These structures are built by individuals following a simple set of rules, slightly varying within and among species, to produce a large diversity of shapes. However, little is known about the origin and evolution of the behavioral mechanisms regulating nest structures. In this study, we discuss the perspective of inferring the evolution of collective behaviors behind pattern formations using a phylogenetic framework. We review the collective behaviors that can be described by a single set of behavioral rules, and for which variations of the environmental and behavioral parameter values produce diverse patterns. We propose that this mechanism could be at the origin of the pattern diversity observed among related species, and that, when they are placed in the proper conditions, species have the behavioral potential to form patterns observed in related species. The comparative analysis of shelter tube construction by lower termites is consistent with this hypothesis. Although the use of shelter tubes in natural conditions is variable among species, most modern species have the potential to build them, suggesting that the behavioral rules for shelter tube construction evolved once in the common ancestor of modern termites. Our study emphasizes that comparative studies of behavioral rules have the potential to shed light on the evolution of collective behaviors.journal articl

Collective Construction by Termite-Inspired Robots

Construction usually involves careful preplanning and direct human operation of tools and material. Bringing automation to construction has the potential to improve its speed and efficiency, and to enable building in settings where it is difficult or dangerous for humans to work, e.g., in extraterrestrial environments or disaster areas. Nature provides us with impressive examples of animal construction: in particular, many species of termites build complex mounds several orders of magnitude larger than themselves. Inspired by termites and their building activities, our goal is to develop systems in which large numbers of robots collectively construct human-scale structures autonomously. In this thesis I present TERMES, a system comprised of (1) A high-level control algorithm for decentralized construction of 3D user-specified structures using stigmergy, exploiting implicit rather than explicit communication; and (2) A complete physical implementation where three robots reliably assemble such structures using only local sensing, limited locomotion, and simple control, exploiting embodied rather than explicit intelligence. A major contribution of this work is the translation from abstract models to a real robotic system. I achieved this through careful co-design of algorithms and physical systems and of robots and building material, allowing passive mechanical features to minimize control complexity. To attain reliable performance without relying on costly high-precision sensors and actuators, I put an emphasis on error-tolerant control, making robots able to autonomously detect and recover from small errors. This work advances the aim of engineering collectives of robots that achieve human-specified goals, using biologically-inspired principles for robustness and scalability. While our work is inspired by models of termite construction from the 1970s and 1980s, much is still unknown about how individual termites coordinate and respond to different environmental factors. To address this issue I developed methods and tools to enable high-resolution quantitative data collection on the behavior of individual termites engaged in collective construction in confined experimental arenas. This work advances our ability to study the termites which will hopefully lead to new insights on the design of robust autonomous systems for collective construction.Engineering and Applied Science

Modèle comportemental de la dynamique de construction de la structure épigée du nid chez la fourmi Lasius niger : approches expérimentales et théoriques

La structure épigée du nid de la fourmi Lasius niger, prise comme un exemple typique des structures alvéolaires construites par les insectes sociaux, résulte de l'accumulation d'actes individuels de prise, de transport et de dépôt de matériau. Nous montrons expérimentalement que ces structures émergent d'une coordination indirecte des actes de prise/dépôt par l'activité précédente : les dépôts sont plus fréquents dans les zones de forte densité, et les prises dans les zones de faible densité. Il s'agit donc d'une dynamique auto-organisée où des boucles de rétroaction amplifient des premiers dépôts aléatoires. Au cours du temps, la surface de la structure devient alvéolaire, et le déplacement des fourmis peut être affecté par ses déclivités et ses courbures. A ce stade, le processus de construction présente donc un double couplage de la structure avec d'une part les décisions comportementales de prise et de dépôt, et d'autre part le déplacement des fourmis. Pour ce dernier, nous proposons le modèle du Marcheur de Boltzmann généralisé qui intègre ces effets d'orientation par la structure. Nous proposons enfin une formulation intégrale des échanges de matériau entre points du système, qui intègre tous ces éléments. Ce formalisme confirme le critère d'émergence obtenu par l'analyse linéaire de stabilité classique sur la phase initiale et permet de comprendre les mécanismes essentiels de cette dynamique, en lien direct avec la représentation du phénomène en termes de comportements individuels.Epigenous part of the nest in the ant Lasius niger is a typical example of sponge-like structures built by social insects. It results from accumulated tiny pellets of material which are picked up, moved and dropped by individuals. We show experimentally that these structured patterns emerge from a coordination of individual decisions mediated by the evolving density of material: they pick up more often in depleted zones and drop preferentially in high-density zones. This self-organized process allows random fluctuations in early material density field to be amplified through time. The building then evolves towards a sponge-like structure, so that the surface displays slopes and curvatures, which might in turn affect motion decisions. In late stage, the coupling between density and behavioral decisions is then intricated with coupling between geometry and motion. For the latter, we designed the Generalized Boltzmann Walker model so as to integrate local geometry with random walk. We demonstrate experimentally its relevance for the effect of slopes. Eventually, we analyze the whole process within an analysis of net exchange of material between pairs of locations. We confirm then some results obtained by classical linear stability analysis, and explain essential properties of those dynamics in terms of measured individual behaviors and cognitive properties

As formigas poneromorfas do Brasil

Resultado do projeto "Rede Multidisciplinar de Estudos sobre Formigas Poneromorfas do Brasil", o livro apresenta um conjunto de estudos originais ou revisões bibliográficas que focalizam o comportamento, desenvolvimento e contribuições das formigas poneromorfas para o ecossistema

A complex systems approach to education in Switzerland

The insights gained from the study of complex systems in biological, social, and engineered systems enables us not only to observe and understand, but also to actively design systems which will be capable of successfully coping with complex and dynamically changing situations. The methods and mindset required for this approach have been applied to educational systems with their diverse levels of scale and complexity. Based on the general case made by Yaneer Bar-Yam, this paper applies the complex systems approach to the educational system in Switzerland. It confirms that the complex systems approach is valid. Indeed, many recommendations made for the general case have already been implemented in the Swiss education system. To address existing problems and difficulties, further steps are recommended. This paper contributes to the further establishment complex systems approach by shedding light on an area which concerns us all, which is a frequent topic of discussion and dispute among politicians and the public, where billions of dollars have been spent without achieving the desired results, and where it is difficult to directly derive consequences from actions taken. The analysis of the education system's different levels, their complexity and scale will clarify how such a dynamic system should be approached, and how it can be guided towards the desired performance

A computational model of ant nest morphogenesis

The nests of social insects are not only impressive because of their sheer complexity, but also because they are built from much smaller agents whose work is not centrally coordinated. A central question is therefore how this coordination can lead to such large scale structures. In this paper we present an individual based nest construction model from experimen-tally inspired rules. The coordination of the building pro-cess is achieved through three main ingredients: 1) stigmergy, which implies that the local configuration of the structure is the stimulus which determines how to continue, 2) body tem-plate, where the interaction between the ant’s body and the growing structure determines the proportions of the emerg-ing pattern, and 3) a construction ”pheromone”, a chemical compound capable of triggering building actions. Our sim-ulations show that this simple set of coordination rules can reproduce the key features observed experimentally in the ant Lasius niger, notably the emergence of mushroom-like pillars and layered structures. A sensitivity analysis on the evaporation rate of the construction pheromone shows that a large range of architectures, from dynamic multilayered nests to compact sponge-like structures, can be produced with the same behavioural rules by simply modifying evaporation rate. We discuss the relevance of these results with respect to the variety of nest architectures found in social insects