The numbers of additional steps (S) required to force molecules into monophyly based on tRNA category, amino acid specificity, and organismal constraints using MP analyses of combined tRNA structure and sequence data

The length of the most parsimonious trees derived from the combined data set was 10,083 steps. Each constrained group is given in parentheses. Both chloroplast and mitochondria tRNAs were included in Bacteria. A = Archaea, B = Bacteria, E = Eukarya, V = viruses. Amino acids are indicated by the International Union of Pure and Applied Chemistry (IUPAC) 3-letter nomenclature.