Classification as an Expression of Phylogenetic Relationships

Nelson, Gareth (Department of Ichthyology, The American Museum of Natural History, New York, New York 10024) 1974. Classification as an expression of phylogenetic relationships. Syst. Zool. 22:344–359.—Concepts of phylogenetic relationships are defined, and the possibilities of their expression in a hierarchical classification are explored. Concepts of relationships—either common-ancestor relationships or ancestor-descendant relationships, are precisely and completely expressible in classification, if descendants rather than ancestors are grouped together. Common-ancestor relationships are more efficiently expressed, and are advantageous for groups of unknown or doubtful relationship.