Chalmers Conferences, 9th European Conference on Mathematical and Theoretical Biology

Evolutionary stability and geographic variation of pollination networks
Arndt Telschow, Shoko Sakai

Last modified: 2014-03-28

Abstract


In the last two decades network theory has emerged as an important tool for describing and analyzing complex biological phenomena. In ecology, it has been applied for interactions among different species in the community, and common characteristics of specific types of networks have been well described. More recent studies have focused on factors that shape their structure and evolution as well as possible implications for conservation. However, most of the observed variations in network structure found in empirical datasets are lacking a sound theoretical explanation. Here, we present a game theoretical model of the plant-pollinator mutualism that describes variation in network structure in terms of evolutionary stability. The theoretical analysis revealed (1) multiple stable network structures that form a gradient from specialism toward generalism with decreasing pollinator abundance, and (2) shifts of the network hub from plants to animals along with decreasing pollinator abundance. We tested model predictions by meta-analysis of 56 plant pollinator networks from different geographical regions, and found theory and data to be consistent. The results suggest that availability of pollination service is a key factor to structure pollination networks, and offer a new explanation for geographical variation (e.g. between tropics and temperate), which was long recognized by ecologists.

Keywords


ecological networks; game theory; pollination