Disentangling the co-structure of multilayer interaction networks: degree distribution and module composition in two-layer bipartite networks

Author(s)

Astegiano, Julia ^{[1, 2]} ; Altermatt, Florian ^{[3, 4]} ; Massol, Francois ^{[1, 5]}

Affiliation

^[1] Univ Paul Valery Montpellier, EPHE, CEFE, UMR 5175, CNRS, Univ Montpellier, 1919 Route Mende, F-34293 Montpellier - France

^[2] Univ Nacl Cordoba, Inst Multidisciplinario Biol Vegetal, FCEFyN, CONICET, Cordoba - Argentina

^[3] Swiss Fed Inst Aquat Sci & Technol, Eawag, Dept Aquat Ecol, CH-8600 Dubendorf - Switzerland

^[4] Univ Zurich, Dept Evolutionary Biol & Environm Studies, CH-8057 Zurich - Switzerland

^[5] Univ Lille Sci & Technol, CNRS, UMR Evoecopaleo 8198, SPICI Grp, F-59000 Lille - France

• Document type: Journal article
• Source: SCIENTIFIC REPORTS; v. 7, NOV 13 2017.
• Web of Science Citations: 3

Abstract

Species establish different interactions (e.g. antagonistic, mutualistic) with multiple species, forming multilayer ecological networks. Disentangling network co-structure in multilayer networks is crucial to predict how biodiversity loss may affect the persistence of multispecies assemblages. Existing methods to analyse multilayer networks often fail to consider network co-structure. We present a new method to evaluate the modular co-structure of multilayer networks through the assessment of species degree co-distribution and network module composition. We focus on modular structure because of its high prevalence among ecological networks. We apply our method to two Lepidoptera-plant networks, one describing caterpillar-plant herbivory interactions and one representing adult Lepidoptera nectaring on flowers, thereby possibly pollinating them. More than 50% of the species established either herbivory or visitation interactions, but not both. These species were over-represented among plants and lepidopterans, and were present in most modules in both networks. Similarity in module composition between networks was high but not different from random expectations. Our method clearly delineates the importance of interpreting multilayer module composition similarity in the light of the constraints imposed by network structure to predict the potential indirect effects of species loss through interconnected modular networks. (AU)

• FAPESP's process: 12/04941-1 - Robustness of plant-pollinator networks and fragmented landscapes: the role of plant breeding system and dispersal strategy on plant species persistence
• Grantee: Julia Astegiano
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• FAPESP's process: 11/09951-2 - Plant-pollinator networks robustness to habitat loss: the influence of plant reproductive systems
• Grantee: Julia Astegiano
• Support Opportunities: Scholarships in Brazil - Post-Doctoral