Fig. 1: Multiscale dynamic imaging reveals four distinct cell classes.

a Schematic of large-scale imaging and semantic segmentation of the predation zone. Scalebars = 10 µm. b Example of a single-cell trajectory (yellow line) reconstructed by connecting segmented cell masks of the same cell (green mask) over time. Scalebar = 5 µm. c Example of a semantically segmented large ROI at the predation front containing the masks for M. xanthus (yellow) and E. coli (blue) (left) Scalebar = 100 µm. The zoom of the boxed area shows single segmented cells in high and low cell density areas (right). Scalebar = 20 µm. d Voronoi tessellation of a large ROI at the predation forefront calculated from the middle points of the M. xanthus mask backbones (left) Scalebar = 100 µm. The zoom of the boxed area shows small polygon areas for M. xanthus cells in high M. xanthus cell density regions and large polygon areas for cells in low M. xanthus cell density regions (right). Black arrows point to examples of isolated and densely packed cells. Scalebar = 20 µm. e Long-range clustering of M. xanthus cells in close spatial proximity in a large ROI at the predation forefront (left). Scalebar = 100 µm. The zoom of the boxed area shows several cell clusters of various sizes (right) Scalebar = 20 µm. f 2D Voronoi area-cluster size histogram for wild-type data accumulated from six experimental replicates (see Fig. S1a for single replicated examples). Red, cyan, and blue boxed areas correspond to scout, loner, and swarm cell classes, respectively. g Dimensionality reduction analysis of cluster size and Voronoi area parameters with UMAP. Left, middle, and right panels represent aggregated single cells data points color-coded with cluster size, Voronoi area values or classes as defined by our criteria, respectively. h Examples of single cells masks color-coded with cell classes in wild-type conditions. Escherichia coli cell masks are grey, M. xanthus scouts, loners, and swarms are colored in red, cyan, and blue, respectively. Scale bar is 10 µm. i Spatial occupation of scout, loner and swarm trajectories for wild type at the predation forefront. The yellow line delimitates the predation front, the green arrow indicates the direction in which M. xanthus predator cells move through the prey colony (predation direction). Scalebars = 100 µm. Magnified image on the bottom right shows long scouts trajectories (Scalebar = 15 µm). j 2D Voronoi area-cluster size histogram for A-motile cells (A+S-) data accumulated from four experimental replicates (see Fig. S1a for single replicate examples). Blue arrow highlights the absence of density for large swarms. k 2D Voronoi area-cluster size histogram for S-motile cells (A-S+) data accumulated from four experimental replicates (see Fig. S1a for single replicate examples). l Histogram of gyration radii of scouts cells trajectories in wild type, A-motile (A+S-) and S-motile (A-S+) communities. Shaded areas highlight the standard deviations from the mean (solid line) of six experimental replicates for the wild-type and four replicates for each mutant strains. m Histogram of instantaneous speed of scouts cells in wild type, A-motile (A+S-) and S-motile (A-S+) communities. Shaded areas highlight the standard deviations from the mean (solid line) of six experimental replicates for the wild-type and four replicates for each mutant strains (see Fig. S1g for single replicate examples). Red arrow points to speed values only reached by wild-type cells with both motility systems. n Histogram of movement directionality of scouts cells in wild type, A-motile (A+S-) and S-motile (A-S+) communities with directionality lower than 1 being confined motion, equal to 1 being Brownian motion and larger than 1 being directed motion. Shaded areas highlight the standard deviations from the mean (solid line) of six experimental replicates for the wild-type and four replicates for each mutant strains (see Fig. S1h for single replicate examples).