The Revised Road Map to the Manual

Abstract

The Second Edition of Bergey's Manual of Systematic Bacteriology (the “Systematics”) represents a major departure from the First Edition, as well as from the Eighth and Ninth Editions of the Bergey's Manual of Determinative Bacteriology (the ‘Determinative”), in that the organization of the content follows a phylogenetic framework based on analyses of the nucleotide sequence of the ribosomal small-subunit RNA, rather than one based on phenotypic characters. The connection between systematics and evolution is pervasive but not logically necessary: purely phenetic taxonomies have been widely used in bacteriology; for many bacteriologists, the current “best practice” in bacterial systematics is polyphasic taxonomy, in which both phenotypic and genotypic information are used. Each volume of this edition will have an updated “road map” chapter (at the current rate of description of new taxa, the number of new genera validly published between the first volume and the fifth and last could number well over 500). A related strategy using genomic information for evolutionary studies has been to produce trees based on the presence or absence of orthologous genes in the genomes being analyzed. As new data become available, more precise placement is likely to occur. Higher taxa and genera that have been moved are listed in Table 2, along with the reasons for these moves. While we believe that the current taxonomy is a better reflection of reality than previous versions, we expect that further changes will be made as we work our way through the subsequent volumes and plan for future editions of the Systematics. Keywords: phylogeny; 16S rRNA; archaea; bacteria; taxonomy