Lieu: Brunoy

Abstract: Darwin discussed mutualism (cooperation between members of different species, as in pollination) and interdependence (heath depending on cattle to prevent forest from replacing it). Although much studied (corals and zooxanthellae, migratory birds), mutualism and interdependence have not been integrated into community ecology thinking. Why? Lotka-Volterra equations, its theoretical foundation, focus on competition and predation. By assuming uniform population densities, these equations ensure that selection cannot favor benefiting prey at no cost to oneself, for if an individual does so, all members of its species do so, benefactors and nonbenefactors alike. What is to be done? Human economies suggest how mutualism (like cooperative enterprise) and interdependence at various spatial scalers would enhance the productivity and diversity of natural ecosystems. Many mutualisms (such as pollination and seed dispersal) and relationships of interdependence (such as migration) involve movement. Studies of movement can reveal sucvh relationships. Study of the various sensory, motor and neural adaptations these movements require can suggest how "organismic technology" paces the evolution of mutualism and interdependence.