Emergent behaviour in slime mould environments

Slime moulds are well studied organisms in biology. They are some of the simplest organisms that exhibit complex emergent behaviour. Although individual organisms interact with the environment only by following local rules, slime moulds produce a collective behaviour on a global scale. The modelling of slime mould patterns provides a good testbed for studying emergent behaviour. We have simulated the behaviour of slime moulds on a computer model. In the model, each organism is guided by rules, derived from studies of real organisms. By changing parameters of the simulation, we were able to study some underlying mechanisms behind the emergent behaviour. We have concentrated on the strength of the communication signal and the distance at which the signal is effective. Results show rather unexpectedly that a stronger communication signal does not necessarily reinforce the emergent behaviour and that the effective signal distance does not depend on the density of organisms.