Evaluating the structure of commensalistic epiphyte-phorophyte networks. A comparative perspective of biotic interactions.

Abstract

Abstract: Recent studies have used a network approach to investigate the interaction of epiphytes with host phorophytes at the community level, there is still a lag in the study of commensalistic epiphyte-phorophyte network structure. This is in part because network studies are still scarce and scattered, making it difficult to detect general patterns. To provide a more complete overall perspective on commensalistic epiphyte-phorophyte interaction and their placement with respect to other better studied biotic interactions, we compiled and analysed twelve commensalistic epiphyte-phorophyte networks, and compared them with the same metrics to ant-myrmecophyte, pollination and seed dispersal mutualistic networks. Results showed that epiphyte-phorophyte networks are more generalist and nested, but less modular than the mutualistic ones. Overall, these findings confirmed that the interaction between vascular epiphytes and host phorophytes is predominantly generalist. The study also identified for first time that commensalistic epiphyte-phorophyte networks of interactions are both nested and modular, and hence, are structured in a similar way to most other types of networks that involve coevolutionary interactions.