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The multilayer nature of ecological networks

Nature Ecology & Evolution volume 1, Article number: 0101 (2017) | Download Citation

Abstract

Although networks provide a powerful approach to study a large variety of ecological systems, their formulation does not typically account for multiple interaction types, interactions that vary in space and time, and interconnected systems such as networks of networks. The emergent field of ‘multilayer networks’ provides a natural framework for extending analyses of ecological systems to include such multiple layers of complexity, as it specifically allows one to differentiate and model ‘intralayer’ and ‘interlayer’ connectivity. The framework provides a set of concepts and tools that can be adapted and applied to ecology, facilitating research on high-dimensional, heterogeneous systems in nature. Here, we formally define ecological multilayer networks based on a review of previous, related approaches; illustrate their application and potential with analyses of existing data; and discuss limitations, challenges, and future applications. The integration of multilayer network theory into ecology offers largely untapped potential to investigate ecological complexity and provide new theoretical and empirical insights into the architecture and dynamics of ecological systems.

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Acknowledgements

S.P. was supported by a James S. McDonnell foundation postdoctoral fellowship for the study of complex systems and by a Fulbright postdoctoral fellowship from the US Department of State. M.A.P. was supported by the FET-Proactive project PLEXMATH (FP7-ICT-2011-8; grant no. 317614) funded by the European Commission. We thank L. G. S. Jeub for help with the analysis of multilayer modularity, M. De Domenico for insightful discussions on multilayer networks, K. Lafferty for insightful discussions on the ecology of multilayer networks, and B. R. Krasnov for help with the temporal network data. M.A.P. thanks M. Kivelä and other collaborators for helping to shape his view of multilayer networks and the participants at the first GCEE workshop on Resilience and Recovery of Biological Networks to Environmental Fluctuations for illuminating discussions.

Author information

Affiliations

  1. Department of Ecology and Evolution, University of Chicago, 1101 E 57 Street, Chicago, Illinois 60637, USA.

    • Shai Pilosof
    •  & Mercedes Pascual
  2. Department of Mathematics, University of California, Los Angeles, Los Angeles, California 90095, USA.

    • Mason A. Porter
  3. Oxford Centre for Industrial and Applied Mathematics, Mathematical Institute, University of Oxford, Oxford OX2 6GG, UK.

    • Mason A. Porter
  4. CABDyN Complexity Centre, University of Oxford, Oxford OX1 1HP, UK.

    • Mason A. Porter
  5. Santa Fe Institute, Santa Fe, New Mexico 87501, USA.

    • Mercedes Pascual
  6. Institut des Sciences de l'Evolution, BioDICée team, UMR 5554, Université de Montpellier, CNRS, IRD, EPHE, CC 065, Place Eugéne Bataillon, 34095 Montpellier Cedex 05, France.

    • Sonia Kéfi

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Contributions

S.P. conceived the idea, performed numerical simulations, and analysed the data; M.A.P. contributed insights about the mathematics of multilayer networks and data analysis; M.P. and S.K. contributed insights on the use of multilayer networks in ecology and the interpretation of results; S.P., M.A.P., M.P., and S.K. wrote the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Shai Pilosof.

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    Supplementary information

    Supplementary Figures 1-6; Supplementary Tables 1–6; Supplementary Notes 1–4; Supplementary References

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    Supplementary Data 1

    Raw data for the example temporal network in the Supplementary Information

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DOI

https://doi.org/10.1038/s41559-017-0101

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