Failure Propagation in Cooperating Multicellular Systems

From microbial communities to eukaryotic tissues, biological function often hinges on the exchange of diffusing cooperative factors and public goods. When stressors or statistical fluctuations compromise the population locally, this leads to an interruption of these exchanges near by and creates a cascade of failures. Here we present analytical results on how failure propagates through a multicellular system right before its catastrophic end. We find that the failure of the system progresses on two fronts; through the propagation of a wave from the surface inwards, and simultaneously, a decay of the bulk that may or may not finalize with a sudden collapse. We obtain formulas governing the population dynamics and failure propagation velocity, and fit some of these findings to experimental measurements.