ORIGIN AND EVOLUTION OF CIRCULAR WAVES AND SPIRALS IN DICTYOSTELIUM-DISCOIDEUM TERRITORIES

Randomly distributed Dictyostelium discoideum cells form cooperative t erritories by signaling to each other with cAMP, Cells initiate the pr ocess by sending out pulsatile signals, which propagate as waves, With time, circular and spiral patterns form, We show that by adding spati al and temporal noise to the levels of an important regulator of exter nal cAMP levels, the cAMP phosphodiesterase inhibitor, we can explain the natural progression of the system from randomly firing cells to ci rcular waves whose symmetries break to form double- and single- or mul ti-armed spirals, When phosphodiesterase inhibitor is increased with t ime, mimicking experimental data, the wavelength of the spirals shorte ns, and a proportion of them evolve into pairs of connected spirals, W e compare these results to recent experiments, finding that the tempor al and spatial correspondence between experiment and model is very clo se.