Response diversity is a major driver of temporal stability in complex food webs

Global change constitutes a suite of major threats to biodiversity and ecosystem functioning. These threats can materialise via changes in the temporal stability of ecological communities and the services they provide. However, the majority of research on stability has focused on single trophic level communities and has not yet integrated classic theory about species richness and food web structure with more recent theory centred on response diversity and stochasticity. Using a stochastic bioenergenetic food-web model, we reveal that response diversity is a major driver of community stability. Moreover, positive stability-richness relationships emerge only in the presence of response diversity. In contrast to previous work, food-web structural properties are only secondary drivers of overall community stability, but interact with response diversity to determine the sign of the stability-richness relationship. Our study highlights the complex pathways by which food-web structure and response diversity drive community stability, and raises concerns about how the loss of response diversity may lead to a breakdown of stability and the capacity for these communities to deliver functions and services to human societies.