A Model of Large-Scale Evolution of Complex Food Webs

Institute of Condensed Matter Physics, Darmstadt University of Technology Hochschulstraße 6, D-64289 Darmstadt, Germany

^* E-mail: guill@fkp.tu-darmstadt.de

Abstract

A simple model of biological evolution of community food webs is introduced. This model is based on the niche model, which is known to generate model food webs that are very similar to empirical food webs. The networks evolve by speciation and extinction. Co-extinctions due to the loss of all prey species are found to play a major role in determining the longterm shape of the food webs. The central aim is to design the model such that the characteristic parameters of the niche model food webs remain in realistic intervals. When the mutation rule is chosen accordingly, it is found that food webs with a complex, biologically meaningful structure emerge and that the statistics of extinction events agrees well with that observed in the paleontological data.