Number of newly defined groups when iterating minimum group size (mC) from 1000 to 5 in decrements of 5 for four minimum branch lengths (mL). Only groups from 150 to 5 are shown for clarity. A non-linear scale is used for the Y-axis to highlight differences in assignments for large groups (missing data points mean that no groups were assigned for that iteration). The total number of defined groups for these settings was 4197, 1582, 699 and 356 for 0.01, 0.02, 0.03 and 0.04 respectively. The default mL setting for grouping is 0.02 (boxed).