A Comparison of Branching Diagrams Derived by Various Phenetic and Cladistic Methods

Abstract

Data for 20 binary characters for 18 hypothetical evolutionary units, members of "Dendrogrammaceae," have been analyzed using various phenetic and cladistic methods. Phenograms from single link, complete link, UPGMA, and WPGMA cluster analysis, shortest spanning tree diagrams, and cladograms from groundplan-divergence, Wagner tree, and character compatibility analyses were constructed. The phenograms and cladograms derived from these analyses were compared with respect to topological distance matrices derived from each. Shortest spanning tree phenograms and cladograms were compared for the number and sequence of character changes occurring on each. From these comparisons, the advantages and limitations of each method as a means for expressing evolutionary relationships among organisms are discussed and a series of recommendations is outlined. Each method can contribute to the development of an estimate of the evolutionary history for a group of organisms and no single method is best for such studies.