An investigation of protistan phylogeny using a numerical taxonomy (cluster) analysis of mitotic systems.

Fourteen mitotic characteristics of 83 species, or groups of species, representing 134 species spread among the "fungi", "algae", "protozoa" and "related" organisms are analyzed by computer-aided cluster analysis techniques. The resultant clusters are represented as phenograms that indicate the degree of similarity among the mitotic systems considered. When compared with other criteria, some clusters correlate well with established taxa but others contain a heterogeneous array of species. Some established taxa are widely dispersed. Some of these "deviant" clusters are probably artefacts of the methodology but others are considered to indicate novel but true common ancestry. It is concluded that this type of analysis and data have phylogenetic value but must be used with considerable care.