Ecosystems are complex systems the dynamics of which are hard to understand and predict. The relation between biodiversity and the biotic interactions that it harbours (trophic links, mutuality, parasitism, commensalism, etc.) is an important component of the functioning of ecosystems, and modelling it is a delicate task. Since the influential works of Lotka-Volterra based on models of competitive exclusion, numerous other works have been led to try and solve the issue of coexistence of species in complex ecosystems (e.g. Hubbell 2001).
These interaction networks are often modelled in the form of graphs linking species (the knots) to one another, through links (the awns) characterizing and quantifying the interactions between themselves. If the functioning of these networks and the study of their flux is done by analysis of differential equations (Proulx et al. 2005), their structure can be modelled with the tools of the theory of graphs (Urban et al. 2009). Nevertheless, these equations are not well suited to drastic changes in the structure (topology) of these networks, as it is often observed in the case of disrupted ecosystems (climatic changes, land usage, invasive species...). We propose here to formalize these ecological interaction networks through formal grammars, and to model their dynamics with the help of this original tool (Chomsky 1956).
Speaker
Aurélien Puiseux, Ecole Normale Supérieure, France
Organisers
Department of Ecology, French Institute of Pondicherry.
Venue
Parampara room, French Institute of Pondicherry, 11, Saint Louis Street, Pondicherry - 605 001.
