The Microbial Cocktail Party: Collective Communication of Spirostomum in Turbulent Noise

Microbial populations must transport material and information across space and time while contending with environmental noise, yet how noise reshapes population-level organization in ecological settings remains unclear. In this study, we investigate how the collective swimming behavior of Spirostomum ciliates responds to noise in the form of fluid turbulence. We first characterize baseline collective behaviors in a quiescent background, such as clustering and trail following, through quantitative video analysis. We then introduce controlled turbulence by generating two-dimensional Faraday waves, enabling us to probe how mechanical noise perturbs population structure. Initially, turbulence disrupts coordination within the Spirostomum population, but over time, the ciliates recover traces of their collective organization. These results suggest that Spirostomum populations exhibit learning-like adaptation that restores collective behavior under noisy conditions, revealing a potential biological advantage for survival in dynamic fluid environments. Our findings bridge microbial ecology and active matter physics in addition to providing a platform to probe noise-coordination trade-offs in simple organisms.