The role of migration in a spatial extension of the Webworld eco-evolutionary model

Abstract

We extend an eco-evolutionary food web model to a spatially-explicit metacommunity model which features migration of populations between multiple local sites on the same time-scale as feeding and reproduction. We study how factors including the implementation and rate of dispersal, properties of the local environments, and the spatial topology of the metacommunity interact to determine the local and global diversity and the degree of synchronisation between local food webs. We investigate the influence of migration on the stability of local networks to perturbation, and simulate a 5 × 5 spatial arrangement of cells, demonstrating that combining adaptive migration and heterogeneous habitats allows distinct food webs to coevolve from the beginning of the simulation. When coupling food webs by diffusion migration after an initial period of isolation, the Webworld model can construct metacommunities of distinct food webs if the local sites have spatially-homogeneous environmental parameters. If the sites have heterogeneous parameters, synchronisation between food webs increases greatly, but this can be offset by a greater number of sites and less-connected spatial topologies.