How Many Species on Earth? 8.7 Million

Most precise estimate ever is based on novel, validated analytical technique;
Yet to be discovered, described, catalogued: 91% of marine species, 86% of species overall

Eight million, seven hundred thousand species (give or take 1.3 million).

That is a new, estimated total number of species on Earth -- the most precise calculation ever offered -- with 6.5 million species found on land and 2.2 million (about 25 percent of the total) dwelling in the ocean depths.

Announced 23 August 2011, by Census of Marine Life scientists, the estimate is based on an innovative, validated analytical technique that dramatically narrows the range of previous estimates. Until now, the number of species on Earth was said to fall somewhere between 3 million and 100 million.

Furthermore, the study, published in PLoS Biology, says a staggering 86% of all species on land and 91% of those in the seas have yet to be discovered, described and catalogued.

• Lead Figure Legend: Predicting the global number of species in Animalia from their higher taxonomy.
  (A–F) The temporal accumulation of taxa (black lines) and the frequency of the multimodel fits to all starting years selected (graded colors). The horizontal dashed lines indicate the consensus asymptotic number of taxa, and the horizontal grey area its consensus standard error. (G) Relationship between the consensus asymptotic number of higher taxa and the numerical hierarchy of each taxonomic rank. Black circles represent the consensus asymptotes, green circles the catalogued number of taxa, and the box at the species level indicates the 95% confidence interval around the predicted number of species.

Editor's Note

• Also, see: The Historical eBook On the Origin of Species in the Encyclopedia of Earth.