Curation of groups using GRUNT before and after database updates. (a) An ungrouped tree with interior nodes labeled s1 to s5 and parent branch e0. The grouping function (addG) identifies that e0 satisfies a minimum branch length (mL) and/or bootstrap support (mS) and that the group contains at least a minimum number of taxa (mC). (b) The naming rules (see text) are applied and the group-name S is proposed and recorded in the XML file. (c) The name is assigned to the newly formed group. (d) New sequences are added to an existing tree as part of an update, and a new sequence, s', is placed basal to group S. (e) The ungrouping function (rmvG) removes groups with branch-lengths below mL and/or mS, in this example e1 is not supported and the group S is removed. (f) The grouping and naming tools are then reapplied and identify the new stable parent branch e2 which then reforms the group S. Note that the name for group S may not be the same as in 1d depending on the taxon composition of the newly formed group.