(A) The unrooted three-domain tree derived by phylogenetic analysis of 16S rRNA and other information-processing genes. (B) The rooted three-domain tree. (C) The network of life. A: archaea ...

Of note, the model does not require prior assumptions regarding tree topology ... more precise estimates of phylogenetic relationships than currently popular unrooted methods.

These are Jukes-Cantor distances based on number of mtDNA sequence differences. [See Glossary and pp. 91-93 of Hall, B.G. 2001. Phylogenetic Trees Made Easy. Sinauer, for more on evolutionary models ...