Fig. 1. The motile behavior of Dictyostelium moving on gelatin. (A-C) Stacked cell outlines, overlaid with a centroid track, from three representative cells of each type; wild-type, mlcE^– and mhcA^– cells. Examples of cells moving randomly at fast (1), intermediate (2) and slow (3) speeds, for each cell type, over a 3-minute period are shown. (A'-C') Rose plots, showing the total distance traveled and the directionality of movement for each cell type during a 3-minute period. Bar, 5 µm. (D-F) Summary histograms of the mean relative changes in instantaneous speed (D), persistence (E) and spread area (F) with respect to the wild-type value that was set to 100% for wild-type (black bar), mlcE⁺ (gray bar), mlcE^– (striped bar) and mhcA^– cells (open bar, n=9). Asterisks indicate statistically significant differences compared with wild-type cells (P<0.05), using a Student's t-test, assuming unequal variances.