Metacommunity robustness to invasion in mutualistic and antagonistic networks

One of the most significant threats to biodiversity is alien species invasion, and consequently understanding and

predicting biological invasions has become an important issue in ecology. While numerous studies have explored

the effect of community diversity and structure on invasion success, a systematic comparative analysis on system

robustness to invasion between antagonistic and mutualistic networks from a metacommunity perspective is still

lacking. Here we seek to address this gap using patch-dynamic models, which integrate local communities into

the landscape metacommunity. We find that both mutualistic and antagonistic metacommunities displayed

qualitatively similar responses to species invasion, except for animal invasion in antagonistic networks. Specifically, increasing network size and connectance generally promoted metacommunity persistence, while

nestedness (negative) and modularity (positive) had contrasting effects on metacommunity robustness to invasion. However, these structural effects were strongly dependent on the generalization levels of both invader and

the resident species it displaces. Overall, this study provides new and more general insights into how alien

species are well integrated into native networks and how they affect metacommunity persistence.