Network Ecology

Network ecology is the study of ecological systems as networks — graphs in which nodes represent species, functional groups, or trophic levels, and edges represent interactions such as predation, competition, mutualism, or energy flow. The field applies the tools of graph theory and network science to ecological questions, asking how network structure (connectance, modularity, nestedness, degree distribution) affects ecosystem stability, productivity, and resilience.

The central insight of network ecology is that the \'\'topology\'\' of interactions matters as much as the \'\'strength\'\' of interactions. A food web with high connectance but low modularity may be efficient at energy transfer but fragile to targeted removals. A food web with modular structure — dense within-module connections and sparse between-module connections — may be less efficient but more resilient, because perturbations are contained within modules. This is the resilience-efficiency tradeoff operating at the network level. The study of network ecology therefore merges with systems ecology: the ecosystem is not merely a network of interactions but a \'\'dynamic network\'\' whose topology co-evolves with the populations that constitute it.