Loops and autonomy promote evolvability of ecosystem networks

TL;DR

This study demonstrates that ecological network structures, especially loops and species autonomy, significantly influence ecosystem evolvability, with implications for ecosystem management and intervention strategies.

Contribution

The paper introduces a novel application of the NK model to ecological networks, linking network structure features to evolvability, which was previously underexplored.

Findings

More feeding loops increase evolvability.

Lower trophic link density enhances potential for heritable variation.

Network autonomy predicts ecosystem evolvability.

Abstract

The structure of ecological networks, in particular food webs, determines their ability to evolve further, i.e. evolvability. The knowledge about how food web evolvability is determined by the structures of diverse ecological networks can guide human interventions purposefully to either promote or limit evolvability of ecosystems. However, the focus of prior food web studies was on stability and robustness; little is known regarding the impact of ecological network structures on their evolvability. To correlate ecosystem structure and evolvability, we adopt the NK model originally from evolutionary biology to generate and assess the ruggedness of fitness landscapes of a wide spectrum of model food webs with gradual variation in the amount of feeding loops and link density. The variation in network structures is controlled by linkage rewiring. Our results show that more feeding loops and lower trophic link density, i.e. higher autonomy of species, of food webs increase the potential for the ecosystem to generate heritable variations with improved fitness. Our findings allow the prediction of the evolvability of actual food webs according to their network structures, and provide guidance to enhancing or controlling the evolvability of specific ecosystems.