"Under the emergent facilitation hypothesis, size-selective predators create a niche for another predator through facilitating the availability of previously scarce size-classes of prey by reducing competition amongst them. Emergent consumer facilitation has been proposed to give rise to Alternative Stable States (ASS) in species composition of ecological communities. There is a great deal of interest in ASS due to being linked to fisheries collapse and explaining biodiversity loss. The objectives of this proposal are to determine the likelihood of emergent consumer facilitation in an experimental aquatic food web with increasing biological realism, to generalise ecological theory of the role of facilitation in the dynamics of ecological communities and to determine the role of indirect facilitative interactions between consumers on the creation of, and shifts between, Alternative Stable Ecological Communities. This research will be undertaken using State-of-the-Art aquaria, mesocosm, modelling and whole lake approaches in a well studied boreal aquatic ecosystem in northern Sweden. The objectives are highly feasible and will be achieved through the establishment of a structured workplan and the strong science and complementary skills training by Professor Persson and his collaborators Professors De Roos and Diehl. Training objectives in experimentation, modelling and analysis linked to each scientific objective, are designed to increase my scientific maturity. And the mobility proposed is genuine, both in terms of geography, ecology and in exposure to new skills for both myself and the host research group (e.g. mesocosms, comparative analysis). Ultimately, the development of my track-record in the study of structured community dynamics, and the benefit of working with a world-class interdisciplinary research team will contribute to European excellence through advancing cutting-edge theory and comprehensive understanding of what creates biodiversity."