Figure 2
From: Field et al. Redux.
Metazoan phylogenies using small subunit ribosomal RNA data. (A) A recapitulation of the original Field et al. analysis using all original sequences in dataset 1. Three main errors are seen: (1) the cnidarians Hydra and Metridium (yellow) are separated from other Metazoans; (2) the flatworm Dugesia is separated from other Lophotrochozoans (red); and (3) the urochordate Styela is separate from other chordates (light blue). (B) Tree using the original data (dataset 1) re-analysed with a 1988 Maximum Likelihood method. Metazoa and chordates are now monophyletic. (C) Analysis of full length SSU sequences with long branched Dugesia replaced by shorter branched Macrostomum (dataset 2) and analysed with modern ML methods (GTR+I+G model). The flatworm is found with the other Lophotrochozoa. Arthropods are in green, echinoderms are in dark blue.