E. Stackebrandt et al., XENORHABDUS AND PHOTORHABDUS - ARE THEY SISTER GENERA OR ARE THEIR MEMBERS PHYLOGENETICALLY INTERTWINED, Symbiosis, 22(1-2), 1997, pp. 59-65
The evolution of an organism can be considered as the sum or mean of t
he evolution of its genes. Thus, the restriction of the phylogenetic a
nalysis to a single molecule, such as the most widely used 16S rDNA, h
ighlights the evolution of the molecule but not necessarily the evolut
ion of the organisms from which the molecule was isolated for analysis
. For a few groups of bacteria more than only a single conservative mo
lecule has been analysed; most of these data sets agree with each othe
r and even provide more insight into the evolution and phylogeny of th
e organisms. For the majority of bacterial taxa, however, genealogical
patterns are exclusively based on a single molecule and support for t
he order of lineages must be derived from phenotypic properties of its
members. As additional factors have been identified that influence th
e topology of the branching pattern, the stability of a phylogenetic b
ranching pattern need to be assessed carefully before taxonomic conclu
sions are made.