An age-structured SEIR model simulates the propagation of COVID-19 in the population of Northern Ireland. It is used to identify optimal timings of short-term lockdowns that enable long-term pandemic exit strategies by clearing the threshold for herd immunity or achieving time for vaccine development with minimal excess deaths.

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.

New results are collected using the Webworld model which simulates evolutionary food web construction with population dynamics [1]. We show that it supports a link-species relationship of neither constant link-density nor constant connectance, and new properties for the food webs are calculated including clustering coefficients and stability in the sense of community robustness to species deletion. Time-series for more than 40 properties of the taxonomic and trophic webs are determined over the course of individual simulations. Robustness is found to be positively correlated with connectance, but negatively with diversity, and we study the long-term development of model webs including the distribution of extinction events in a simulation with 10 8 speciation events.

An eco-evolutionary food web model is modified to incorporate a body-size trait, enabling a framework for nonuniform mortality and ecological efficiency between species. Evolved communities feature increased connectance, with according benefits to community robustness, and persistent top predators but reduced omnivory and food chain lengths. Body-size maintains a strong positive correlation to trophic level, but does not correlate to an individual species' contribution to network stability. A spatially-explicit extension of the model assembles large metacommunities with distinct distributions of body-size amongst local food webs.

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