Disentangling the Information in Species Interaction Networks

Shannon's entropy measure is a popular means for quantifying ecological diversity. We explore how one can use information-theoretic measures (that are often called indices in ecology) on joint ensembles to study the diversity of species interaction networks. We leverage the little-known balance equation to decompose the network information into three components describing the species abundance, specificity, and redundancy. This balance reveals that there exists a fundamental trade-off between these components. The decomposition can be straightforwardly extended to analyse networks through time as well as space, leading to the corresponding notions for alpha, beta, and gamma diversity. Our work aims to provide an accessible introduction for ecologists. To this end, we illustrate the interpretation of the components on numerous real networks. The corresponding code is made available to the community in the specialised Julia package EcologicalNetworks.jl.

Automated summary

Shannon's entropy measure is used to quantify ecological diversity, with a fundamental trade-off revealed between species abundance, specificity, and redundancy. The decomposition can be extended to analyze networks over time and space, leading to notions of alpha, beta, and gamma diversity. The work aims to provide an accessible introduction to ecologists, with code available in the EcologicalNetworks.jl package.