Editing Biodiversity (section)

== Number of species ==
{{Main|Global biodiversity}}

According to estimates by Mora et al. (2011), there are approximately 8.7&nbsp;million terrestrial species and 2.2&nbsp;million oceanic species. The authors note that these estimates are strongest for eukaryotic organisms and likely represent the lower bound of prokaryote diversity.<ref name="mora2011">{{cite journal |last1=Mora |first1=Camilo |last2=Tittensor |first2=Derek P. |last3=Adl |first3=Sina |last4=Simpson |first4=Alastair G. B. |last5=Worm |first5=Boris |last6=Mace |first6=Georgina M. |date=23 August 2011 |title=How Many Species Are There on Earth and in the Ocean? |journal=PLOS Biology |volume=9 |issue=8 |pages=e1001127 |doi=10.1371/journal.pbio.1001127 |pmc=3160336 |pmid=21886479 |doi-access=free}}</ref> Other estimates include:
* 220,000 [[vascular plants]], estimated using the species-area relation method<ref>{{cite journal |last1=Wilson |first1=J. Bastow |last2=Peet |first2=Robert K. |last3=Dengler |first3=Jürgen |last4=Pärtel |first4=Meelis |date=1 August 2012 |title=Plant species richness: the world records |bibcode-access=free |journal=Journal of Vegetation Science |volume=23 |issue=4 |pages=796–802 |doi=10.1111/j.1654-1103.2012.01400.x |bibcode=2012JVegS..23..796W |doi-access=free }}</ref>
* 0.7-1&nbsp;million marine species<ref>{{cite journal |last1=Appeltans |first1=W. |last2=Ahyong |first2=S. T. |last3=Anderson |first3=G. |last4=Angel |first4=M. V. |last5=Artois |first5=T. |display-authors=et al. |date=2012 |title=The Magnitude of Global Marine Species Diversity |journal=Current Biology |volume=22 |issue=23 |pages=2189–2202 |doi=10.1016/j.cub.2012.09.036 |pmid=23159596 |doi-access=free|bibcode=2012CBio...22.2189A |hdl=1942/14524 |hdl-access=free}}</ref>
* 10–30&nbsp;million [[insect]]s;<ref>{{cite web |title=Numbers of Insects (Species and Individuals) |url=http://www.si.edu/Encyclopedia_SI/nmnh/buginfo/bugnos.htm |website=Smithsonian Institution |url-status=live |archive-url=https://web.archive.org/web/20240115042918/https://www.si.edu/spotlight/buginfo/bugnos |archive-date= Jan 15, 2024 }}</ref> (of some 0.9&nbsp;million we know today)<ref name="Le Monde newspaper article">{{cite news |last=Galus |first=Christine |date=5 March 2007 |title=Protection de la biodiversité : un inventaire difficile |language=fr |work=Le Monde |url=http://www.lemonde.fr/planete/article/2006/06/27/protection-de-la-biodiversite-un-inventaire-difficile_788741_3244.html |url-status=live |archive-url=https://web.archive.org/web/20230401134829/https://www.lemonde.fr/planete/article/2006/06/27/protection-de-la-biodiversite-un-inventaire-difficile_788741_3244.html |archive-date= Apr 1, 2023 }}</ref>
* 5–10&nbsp;million [[bacteria]];<ref>{{Cite news |date=2006-07-31 |title=Thousands of microbes in one gulp |url=http://news.bbc.co.uk/2/hi/science/nature/5232928.stm |first1=Louisa |last1=Cheung  |website=BBC NEWS |language=en-GB |url-status=live |archive-url= https://web.archive.org/web/20221223220931/http://news.bbc.co.uk/2/hi/science/nature/5232928.stm |archive-date= Dec 23, 2022 }}</ref>
* 1.5-3&nbsp;million [[fungi]], estimates based on data from the tropics, long-term non-tropical sites and molecular studies that have revealed [[cryptic species|cryptic speciation]].<ref>{{cite journal |last=Hawksworth |first=D. L. |date=24 July 2012 |title=Global species numbers of fungi: are tropical studies and molecular approaches contributing to a more robust estimate? |journal=Biodiversity and Conservation |volume=21 |issue=9 |pages=2425–2433 |doi=10.1007/s10531-012-0335-x |bibcode=2012BiCon..21.2425H }}</ref> Some 0.075&nbsp;million species of fungi had been documented by 2001;<ref name="Hawksworth">{{cite journal |last1=Hawksworth |first1=D |year=2001 |title=The magnitude of fungal diversity: The 1.5 million species estimate revisited |journal=[[Mycological Research]] |volume=105 |issue=12 |pages=1422–1432 |doi=10.1017/S0953756201004725 }}</ref>
* 1&nbsp;million [[mite]]s<ref>{{cite web |date=10 November 2003 |title=Acari at University of Michigan Museum of Zoology Web Page |url=http://insects.ummz.lsa.umich.edu/ACARI/index.html |access-date=21 June 2009 |publisher=Insects.ummz.lsa.umich.edu}}</ref>
* The number of [[microbial]] species is not reliably known, but the [[Global Ocean Sampling Expedition]] dramatically increased the estimates of genetic diversity by identifying an enormous number of new genes from near-surface [[plankton]] samples at various marine locations, initially over the 2004–2006 period.<ref>{{cite web |title=Fact Sheet – Expedition Overview |url=http://www.jcvi.org/cms/fileadmin/site/research/projects/gos/Expedition_Overview.pdf |url-status=dead |archive-url=https://web.archive.org/web/20100629133109/http://www.jcvi.org/cms/fileadmin/site/research/projects/gos/Expedition_Overview.pdf |archive-date=29 June 2010 |access-date=29 August 2010 |publisher=[[J. Craig Venter Institute]]}}</ref> The findings may eventually cause a significant change in the way science defines [[species]] and other taxonomic categories.<ref>{{cite news |last1=Mirsky |first1=Steve |title=Naturally Speaking: Finding Nature's Treasure Trove with the Global Ocean Sampling Expedition; and Natural Products Chemistry |url=https://www.scientificamerican.com/podcast/episode/74f46951-e7f2-99df-37873c5b678dc19d/ |work=Scientific American |date=21 March 2007 }}</ref><ref>{{cite journal |last1=Gross |first1=Liza |title=Untapped Bounty: Sampling the Seas to Survey Microbial Biodiversity |journal=PLOS Biology |date=13 March 2007 |volume=5 |issue=3 |pages=e85 |doi=10.1371/journal.pbio.0050085 |doi-access=free |pmid=20076663 |pmc=1821062 }}</ref>

Since the rate of extinction has increased, many extant species may become extinct before they are described.<ref>{{cite news |last=McKie |first=Robin |date=25 September 2005 |title=Discovery of new species and extermination at high rate |newspaper=The Guardian |location=London |url=https://www.theguardian.com/science/2005/sep/25/taxonomy.conservationandendangeredspecies}}</ref> Not surprisingly, in the [[Animal|Animalia]] the most studied groups are [[birds]] and [[mammals]], whereas [[fishes]] and [[arthropods]] are the least studied animal groups.<ref>{{cite journal |last1=Bautista |first1=Luis M. |last2=Pantoja |first2=Juan Carlos |date=2005 |title=What species should we study next? |journal=Bulletin of the British Ecological Society |volume=36 |issue=4 |pages=27–28 |hdl-access=free |hdl=10261/43928}}</ref>