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Inferring species roles in metacommunity structure from species co-occurrence networks.

ABSTRACT: A long-standing question in community ecology is what determines the identity of species that coexist across local communities or metacommunity assembly. To shed light upon this question, we used a network approach to analyse the drivers of species co-occurrence patterns. In particular, we focus on the potential roles of body size and trophic status as determinants of metacommunity cohesion because of their link to resource use and dispersal ability. Small-sized individuals at low-trophic levels, and with limited dispersal potential, are expected to form highly linked subgroups, whereas large-size individuals at higher trophic positions, and with good dispersal potential, will foster the spatial coupling of subgroups and the cohesion of the whole metacommunity. By using modularity analysis, we identified six modules of species with similar responses to ecological conditions and high co-occurrence across local communities. Most species either co-occur with species from a single module or are connectors of the whole network. Among the latter are carnivorous species of intermediate body size, which by virtue of their high incidence provide connectivity to otherwise isolated communities playing the role of spatial couplers. Our study also demonstrates that the incorporation of network tools to the analysis of metacommunity ecology can help unveil the mechanisms underlying patterns and processes in metacommunity assembly.

SUBMITTER: Borthagaray AI

PROVIDER: S-EPMC4150328 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Inferring species roles in metacommunity structure from species co-occurrence networks.

Borthagaray Ana I AI Arim Matías M Marquet Pablo A PA

Proceedings. Biological sciences 20141001 1792

A long-standing question in community ecology is what determines the identity of species that coexist across local communities or metacommunity assembly. To shed light upon this question, we used a network approach to analyse the drivers of species co-occurrence patterns. In particular, we focus on the potential roles of body size and trophic status as determinants of metacommunity cohesion because of their link to resource use and dispersal ability. Small-sized individuals at low-trophic levels ...[more]

PMID: 25143039

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Inferring species roles in metacommunity structure from species co-occurrence networks.

Publications

Inferring species roles in metacommunity structure from species co-occurrence networks.

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