Propagating spiral waves in a P. aeruginosa colony

Upper: time-lapse phase-contrast images. Lower: wavefronts of the propagating spiral waves (labelled as white traces) traced by the variation of light intensity in the phase-contrast images. The elapsed time is indicated by the time stamp (format: hh:mm:ss). Scale bar, 500 μm. See: Liu et al., Nature Physics (2024): 1-7.