Viruses as Winners in the Game of Life

Annu Rev Virol. 2016 Sep 29;3(1):197-214. doi: 10.1146/annurev-virology-100114-054952.


Viruses are the most abundant and the most diverse life form. In this meta-analysis we estimate that there are 4.80×1031 phages on Earth. Further, 97% of viruses are in soil and sediment-two underinvestigated biomes that combined account for only ∼2.5% of publicly available viral metagenomes. The majority of the most abundant viral sequences from all biomes are novel. Our analysis drawing on all publicly available viral metagenomes observed a mere 257,698 viral genotypes on Earth-an unrealistically low number-which attests to the current paucity of viral metagenomic data. Further advances in viral ecology and diversity call for a shift of attention to previously ignored major biomes and careful application of verified methods for viral metagenomic analysis.

Keywords: biogeography; metagenomics; phage abundance; phage diversity; phage ecology; viruses.

Publication types

  • Meta-Analysis
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Bacteriophages / classification*
  • Bacteriophages / genetics*
  • DNA Viruses / classification
  • DNA Viruses / genetics
  • Genome, Viral / genetics*
  • Geologic Sediments / virology*
  • Metagenome / genetics*
  • RNA Viruses / classification
  • RNA Viruses / genetics
  • Soil Microbiology