Discussion papers

CPM-13-222 - 17 October 2013

An Individual-Based Model of the Impact of Human Beings on an Ecosystem

Bruce Edmonds


A complex individual-based meta-population simulation is presented which allows the exploration of systemic change within an ecosystem. This model exhibits a variety of different states but can show the build up of multi-trophic levels of food web and dynamics of species. The model is composed of a set of patches, each well mixed, with slow rates of migration occurring between neighbouring patches. The impact of humans upon this is done in two different ways: firstly by the systematic “blocking” of dimensions of inter-species interaction and, secondly, by the introduction of individuals to represent humans which have a social (rather than genetic) set of affordances. The outcomes of such experiments is analysed at a number of levels. The results show that although some general relationships between settings and outcomes are discernible, some of the meaningful patterns are context-specific. Some hypotheses about the conditions that maintain some ecological diversity despite the impact of human individuals are suggested.

Graphical Abstract