ABSTRACT
The last 15 years have seen tremendous advances in the determination of evolutionary relationships between all living organisms, with the use of 16S rRNA genes to determine phylogenetic relationships, providing not only a unifying methodology for evolutionary analysis, but in addition resulting in a new tree of life, divided into the three domains: Bacteria, Archaea and Eucarya (Woese et al., 1990). The establishment of the ribosomal database project (RDP) (Larsen et al., 1993) which now contains 16S rRNA gene sequences from over 10,000 organisms, has facilitated the construction of phylogenies encompassing all three domains of life as well as numerous smaller, more specific phylogenies.
