Modéliser la croissance des populations mutualistes : une question scientifique complexe

• Published in: Philosophia scientiae Vol. 15; no. 3; pp. 223 - 251
• Main Author: Olivier Perru
• Format: Journal Article
• Language: German
• Published: Éditions Kimé 01-10-2011
• ISSN: 1281-2463; 1775-4283
• DOI: 10.4000/philosophiascientiae.697

The aim of this paper is an epistemological analysis of mutualism modeling. From the Lotka-Volterra analysis, we look for some characteristics and epistemological inadequacies of this class of models. Volterra s’mathematical work was a response to a particular ecological situation. This situation is the rupture of the equilibrium between competing associated species. Starting from equations describing variations in competing populations, a change of sign is enough to transform them into equations describing variations in numbers of mutualistic populations. In terms of modeling, competition models have attracted a lot of attention while mutualism has been relatively neglected. If the relative growths of the two populations are the same, applied to mutualism Lotka-Volterra models indicate an equilibrium point. These models are used to make a distinction between obligatory and accidental mutualism. To be considered valid these models need to give an equilibrium point and provide the dominant characteristic of biological mutualism (obligatory or accidental). From the end of the 90s, some researchers have developed more realistic bio­logical models that allow a transition from parasitism to mutualism depending on the densities of the two partners. From an epistemological viewpoint, these models remain relative to a population level. They refer to the biological pop­ulations studies but they need to be complemented by an analysis of the same biological phenomenon at an individual level.