Comparing species interaction networks along environmental gradients: Networks along environmental gradients

Pellissier, Loïc; Albouy, Camille; Bascompte, Jordi; Farwig, Nina; Graham, Catherine; Loreau, Michel; Maglianesi, Maria Alejandra; Melián, Carlos J.; Pitteloud, Camille; Roslin, Tomas; Rohr, Rudolf P.; Saavedra, Serguei; Thuiller, Wilfried; Woodward, Guy; Zimmermann, Niklaus E.; Gravel, Dominique

doi:10.1111/brv.12366

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Journal article

Comparing species interaction networks along environmental gradients: Networks along environmental gradients

Pellissier, Loïc Landscape Ecology, Institute of Terrestrial Ecosystems, ETH Zürich, Zwitzerland - Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
Albouy, Camille Landscape Ecology, Institute of Terrestrial Ecosystems, ETH Zürich, Zwitzerland - Swiss Federal Research Institute WSL, Birmensdorf, Switzerland - IFREMER, unité Ecologie, Nantes, France
Bascompte, Jordi Department of Evolutionary Biology and Environmental Studies, University of Zürich, Switzerland
Farwig, Nina Conservation Ecology, Faculty of Biology, Philipps-Universität Marburg, Germany
Graham, Catherine Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
Loreau, Michel Centre for Biodiversity Theory and Modelling, CNRS and Paul Sabatier University, Moulis, France
Maglianesi, Maria Alejandra Vicerrectoría de Investigación, Universidad Estatal a Distancia, San José, Costa Rica - BiK-F, Senckenberg Gesellschaft für Naturforschung, Frankfurt am Main, Germany
Melián, Carlos J. Department of Fish Ecology and Evolution, Eawag, Kastanienbaum, Switzerland
Pitteloud, Camille Landscape Ecology, Institute of Terrestrial Ecosystems, ETH Zürich, Zwitzerland - Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
Roslin, Tomas Department of Ecology, Swedish University of Agricultural Sciences, Uppsala, Sweden
Rohr, Rudolf P. Department of Biology ? Ecology and Evolution, University of Fribourg, Switzerland
Saavedra, Serguei Department of Civil and Environmental Engineering, MIT, Cambridge, USA
Thuiller, Wilfried University of Grenoble Alpes, CNRS-LECA, Grenoble, France
Woodward, Guy Department of Life Sciences, Imperial College London, Berkshire, UK
Zimmermann, Niklaus E. Landscape Ecology, Institute of Terrestrial Ecosystems, ETH Zürich, Zwitzerland - Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
Gravel, Dominique Canada Research Chair in Integrative Ecology, Université de Sherbrooke, Québec, Canada

22.09.2017

Published in:

Biological Reviews. - 2018, vol. 93, no. 2, p. 785–800

English Knowledge of species composition and their interactions, in the form of interaction networks, is required to understand processes shaping their distribution over time and space. As such, comparing ecological networks along environmental gradients represents a promising new research avenue to understand the organization of life. Variation in the position and intensity of links within networks along environmental gradients may be driven by turnover in species composition, by variation in species abundances and by abiotic influences on species interactions. While investigating changes in species composition has a long tradition, so far only a limited number of studies have examined changes in species interactions between networks, often with differing approaches. Here, we review studies investigating variation in network structures along environmental gradients, highlighting how methodological decisions about standardization can influence their conclusions. Due to their complexity, variation among ecological networks is frequently studied using properties that summarize the distribution or topology of interactions such as number of links, connectance, or modularity. These properties can either be compared directly or using a procedure of standardization. While measures of network structure can be directly related to changes along environmental gradients, standardization is frequently used to facilitate interpretation of variation in network properties by controlling for some co‐ variables, or via null models. Null models allow comparing the deviation of empirical networks from random expectations and are expected to provide a more mechanistic understanding of the factors shaping ecological networks when they are coupled with functional traits. As an illustration, we compare approaches to quantify the role of trait matching in driving the structure of plant–hummingbird mutualistic networks, i.e. a direct comparison, standardized by null models and hypothesis‐based metaweb. Overall, our analysis warns against a comparison of studies that rely on distinct forms of standardization, as they are likely to highlight different signals. Fostering a better understanding of the analytical tools available and the signal they detect will help produce deeper insights into how and why ecological networks vary along environmental gradients.

Faculty

Faculté des sciences et de médecine

Department

Département de Biologie

Language