Know more

Ecological networks have been defined as the backbone of biodiversity, describing who interacts with whom in nature for a given location and time. Understanding the spatial scaling of biodiversity across the globe is thus a major challenge for ecological research. Even more so given the current threats facing biodiversity due to different components of global change. A good understanding of how species richness (a component of biodiversity) increases with area has been so far achieved; and, to some extent, the mechanisms behind this scaling are understood. However, the same isn’t true for the number and the organization of ecological interactions (another component of biodiversity).

How does network structure change as we increase the spatial scale of observation?

Motivated by basic mechanisms influencing the Species-Area Relationships, like beta-diversity patterns across local communities, the authors set out to discover the fundamental processes behind the spatial scaling of interaction networks. They joined forces with a group of internationally recognized experts in the field of spatial food webs to find the potential ecological drivers of Network-Area Relationships.

The authors developed a theoretical and predictive framework to understand the variation of the properties of ecological networks (e.g., connectivity, trophic level composition, trophic chain length) across spatial scales; from small to large areas. With three simple theoretical models, they tested the effect of specific spatial processes (e.g., dispersal) on community assembly and structure, which allowed them to present a number of testable predictions on network-area relationships for multi-trophic communities.

The researchers have gathered biotic interactions data from ecological systems across the globe, from different regions, habitats, and interaction types across different spatial scales. The next step will be thus to use this data to reveal the scaling of interaction networks in space and, based on the shape of these relationships and their theoretical predictions, try to infer the possible spatial processes behind them.

Led by a team strongly supported by the LabEx - Nuria Galiana’s PhD (first author of the article) being funded by TULIP on José M. Montoya’s Junior Package (José being the last author of the article), this study opens new research avenues towards a better understanding of the spatial scaling of biodiversity, which is crucial to generate predictions of potential effects on ecological communities of habitat loss and fragmentation in a changing world.