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Universal Tree of Life

  1. James R Brown

Published Online: 27 JAN 2006

DOI: 10.1038/npg.els.0004125



How to Cite

Brown, J. R. 2006. Universal Tree of Life. eLS. .

Author Information

  1. Bioinformatics, Genetics Research, GlaxoSmithKline Pharmaceuticals, Collegeville, Pennsylvania, USA

Publication History

  1. Published Online: 27 JAN 2006


The universal tree of life represents the proposed evolutionary relationships among all cellular life forms, which are classified into three main urkingdoms or domains; the Archaea (archaebacteria), Bacteria (eubacteria) and Eucarya (eukaryotes). While the flood of whole genome deoxyribonucleic acid (DNA) sequences from species in all the three domains have provided rich data sets to reconstruct the universal tree, it has also raised important new questions about the evolution of life. In particular, early genome evolution might have been largely shaped by the widespread occurrence of lateral or horizontal gene transfer between distantly related species from different domains.


  • universal tree of life;
  • evolution;
  • archaebacteria;
  • bacteria;
  • eukaryotes