MUTUALISTIC INTERACTIONS ARE CRUCIAL FOR MAINTAINING PLANT BIODIVERSITY.

Recent advances in complex networks research allow to take a closer look at various ecological interactions that involve both plants and animals at the level of ecosystems. Especially mutualistic interactions (eg. pollination) play a crucial role in generating and sustaining biodiversity of terrestrial ecosystems. Many authors regard them as "architecture of biodiversity" because usually they connect dozens or even hundreds of species, forming large and complex networks of reciprocally beneficial interactions. The structure of such networks is highly heterogeneous and asymmetric: most of the species are rather weakly connected, while some of taxa develop much stronger relationships. Based on our studies in semi-natural habitats in NE Poland we will demonstrate how new mathematical tools allow to analyse the pollination network structure and can be farther applied to indicate "keystone" species which may be important in determining the stability of the studied ecosystems. [ABSTRACT FROM AUTHOR]