1. The real ‘domains’ of life
David A. Walsh, W. Ford Doolittle 
Current Biology 
Volume 15, Issue 7, Pages R237-R240 (April 2005)
DOI: /j.cub
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2. Figure 1
A diagrammatic representation of the organization of life into three domains based on SSU rRNA gene sequence similarity.
Blue branches represent those groups with cultured representatives; black branches represent groups only known from culture-independent environmental studies. The branching orders within the Archaea, Bacteria and Eukarya are based on those presented in Rappe and Giovannoni (2003), Forterre et al. (2002) and Simpson and Roger (2004), respectively.
Current Biology  , R237-R240DOI: ( /j.cub )
Copyright © 2005 Elsevier Ltd Terms and Conditions