How collectively integrated are ecological communities?

Abstract

Beyond abiotic conditions, do population dynamics mostly depend on a species' direct predators, preys and conspecifics? Or can indirect feedback that ripples across the whole community be equally important? Determining where ecological communities sit on the spectrum between these two characterizations requires a metric able to capture the difference between them. Here we show that the spectral radius of a community's interaction matrix provides such a metric, thus a measure of ecological collectivity, which is accessible from imperfect knowledge of biotic interactions and related to observable signatures. This measure of collectivity integrates existing approaches to complexity, interaction structure and indirect interactions. Our work thus provides an original perspective on the question of to what degree communities are more than loose collections of species or simple interaction motifs and explains when pragmatic reductionist approaches ought to suffice or fail when applied to ecological communities.From a careful analysis of the matrix of interactions between species, we derive a measure of collectivity that integrates existing approaches to complexity and collective integration.image

Keywords

complexity; eigenvalues; holism; indirect interactions; interaction networks; interaction structure; Lotka-Volterra models; press perturbations; reductionism; stability

Published in

Ecology Letters
2024, volume: 27, number: 1, article number: e14358
Publisher: WILEY

SLU Authors

• Zelnik, Yuval

  • Department of Ecology, Swedish University of Agricultural Sciences
    
  • Department of Crop Production Ecology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Ecology

Publication identifier

• DOI: https://doi.org/10.1111/ele.14358

Permanent link to this page (URI)

https://res.slu.se/id/publ/128263