Interaction intimacy organizes networks of antagonistic interactions in different ways

Abstract

Interaction intimacy, the degree of biological integration between interacting individuals, shapes the ecology and evolution of species interactions. A major question in ecology is whether interaction intimacy also shapes the way interactions are organized within communities. We combined analyses of network structure and food web models to test the role of interaction intimacy in determining patterns of antagonistic interactions, such as hostparasite, predator -prey and plant -herbivore interactions. Networks describing interactions with low intimacy were more connected, more nested and less modular than high-intimacy networks. Moreover, the performance of the models differed across networks with different levels of intimacy. All models reproduced well low-intimacy networks, whereas the more elaborate models were also capable of reproducing networks depicting interactions with higher levels of intimacy. Our results indicate the key role of interaction intimacy in organizing antagonisms, suggesting that greater interaction intimacy might be associated with greater complexity in the assembly rules shaping ecological networks.

Agricultural intensification drives changes in hybrid network robustness by modifying network structure

“…Modularity, a common feature of antagonistic networks (Krause et al ; Thébault & Fontaine ), is the tendency for species to form densely connected groups, or “modules,” of interacting species with relatively fewer interactions between modules (Olesen et al ). In dynamic models, modularity promotes local stability of antagonistic networks (Thébault & Fontaine ), but reduces their robustness to the loss of specialised species (Pocock et al ), perhaps because of the higher prevalence of reciprocal specialisation in modular networks (Lewinsohn et al ; Pires & Guimaraes ; Hembry et al ). Species richness, connectance, nestedness and modularity are complementary but interrelated network metrics that can all ultimately impact robustness.…”

Assembly of complex plant–fungus networks

“…A potential key factor that determines the number, size and distribution of modules within ecological networks is the intimacy of interspecific interactions789. Most studies of network structure have targeted interactions among free-living species such as plants and their pollinators or seed dispersers or predators and prey2310.…”

Habitat Isolation Reduces the Temporal Stability of Island Ecosystems in the Face of Flood Disturbance

“…A return to environmental stability in the aftermath of flood disturbance, however, is likely to see each island system revert to pre-disturbance levels of complexity and consistency due to re-colonisation from the metacommunity. Thus, metacommunity dynamics may be seen as another possible mechanism for scale invariance in ecological networks, in addition to abundance distributions (Vazquez et al, 2005), interaction intimacy (Pires and Guimarães, 2012), and interaction type .…”