CLASSIFICATION OF EVOLUTIONARY GROUPS WITH UNEVEN SAMPLINGS AND PATCHY EXTINCTIONS

Classifications made by the powerful human grouping instinct are dilat ed (swollen out, enlarged) around any groups that are probably incompl ete for some reason. For example, evidence may suggest that some taxa of a group may have been poorly sampled by collectors. Some small grou ps may be important remnants of major fossil taxa or may have undiscov ered allies. Dilating classifications around such incomplete groups ma y raise them to higher, more appropriate ranks. Dilation control is ra rely provided in computer programs. The Uniter program lets the user g ive more dilation around the smaller clusters. It does so more for the later-linking clusters, based on an assumption that these are more li kely to have missing allies. For clusters of various sizes, the user c an control their individual prominence or concealment. Methods are com pared and discussed with examples. It is concluded that controlled dil ation is essential for the high resolving power one expects to find in computer based classifications of evolutionary groups.