New research proposes a model to explain how simple food webs are formed within a community. A food web links each species with its predators and prey, but it’s not clear how any particular association emerges from a wide range of possible webs. In the present study, researchers describe a principle of mutual replenishment, which applies to pairs of food webs that can be transformed into one another by invasion or extinction of a species. These findings can help predict relationships within communities in the long run, as the shape of the food web affects the dynamics of an ecosystem as a whole.


Graham BellÉtienne Fortier-Dubois

Corresponding author:

Graham Bell, Department of Biology, McGill University, Montreal, QC, Email:

Original paper published in Proceedings of the Royal Society B on September 13, 2017.