Mathematical Simulation of Dictyostelium Pseudoplasmodia Movements

A mathematical model has been developed to simulate the movement of Dictyostelium discoideum slugs. The model allows simulation of random motility in the absence of external stimuli based on spatial and temporal changes in the microenvironment. In addition the effects of external stimuli such as laterally impinging light and thermal gradients have been simulated. The model allows us to study the effect of simultaneous application of different stimuli. A statistical analysis incorporated in the model allows us to evaluate quantitatively the directedness of movement and the angle of deviation from the stimulus direction as well as the angular distribution of track segments in 5° sectors. The results are discussed in comparison with the experimental data obtained in vivo as well as the ecological effects of multiple stimuli.