| Abstract | Several authors have recently commented on the differences between cladograms and phylogenetic trees. Cladograms may be considered branching diagrams of organisms united by unique characters but without any a priori connotation of the special biological relationships implied by the branches. Phylogenetic trees may be considered diagrams which specify the biological relationships between organisms in the genealogical sense (i.e., ancestor-descendant or sister group relationships). The array of possible phylogenetic trees given by Platnick (1977) and others are viable alternates within the phylogenetic system when a series of 3 samples have not been identified as separate species, populations within a single species, or a combination of the two. Identification of the nature of the samples results in an array of evolutionary implications which limits further tree alternates to those which correspond with the assumption made by the investigator. Arguments over the number of alternate phylogenetic trees for any one cladogram revolve around the evolutionary assumptions held by the investigator and not around the mathematically possible permutations derived from the cladogram itself.
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