Evidence for emergent behaviour in the community-scale dynamics of a fungal microcosm

A stochastic cellular automaton for modelling the dynamics of a two-species fungal microcosm is presented. The state of each cell in the automaton dep ends on the state of a predefined neighbourhood via a set of conditional pr obabilities derived from experiments conducted on pairwise combinations of species. The model is tested by detailed comparison with larger-scale exper imental microcosms. By employing different hypotheses which relate the pair wise data to the conditional probabilities in the model, the nature of the local and non-local interactions in the community is explored. The hypothes is that the large-scale dynamics are a consequence of independent interacti ons between species in a local neighbourhood can be excluded at the 5% sign ificance level. The form of the interdependencies is determined and it is s hown that the outcome of the interactions at the local neighbourhood-scale depends on the community-scale patterning of individuals. The dynamics of t he microcosm are therefore an emergent property of the system of interactin g mycelia that cannot be deduced from a study of the components in isolatio n.