Editing Biosphere (section)

=== Extent ===
[[File:Ruppelsvulture.jpg|thumb|upright|Rüppell's vulture]]
[[File:XenophyophoreNOAA.jpg|thumb|[[Xenophyophore]], a barophilic organism, from the [[Galápagos hotspot|Galapagos Rift]]]]
Every part of the planet, from the [[polar region|polar]] ice caps to the [[equator]], features life of some kind. Recent advances in [[microbiology]] have demonstrated that microbes live deep beneath the Earth's terrestrial surface and that the total mass of [[microbial]] life in so-called "uninhabitable zones" may, in [[Biomass (ecology)|biomass]], exceed all animal and plant life on the surface. The actual thickness of the biosphere on Earth is difficult to measure. Birds typically fly at altitudes as high as {{convert|1800|m|ft mi|abbr=on}} and fish live as much as {{convert|8372|m|ft mi|abbr=on}} underwater in the [[Puerto Rico Trench]].<ref name="Campbell 2006" />

There are more extreme examples for life on the planet: [[Rüppell's vulture]] has been found at [[altitude]]s of {{convert|11300|m|ft mi|abbr=off}}; [[bar-headed goose|bar-headed geese]] migrate at altitudes of at least {{convert|8300|m|ft mi|abbr=on}}; [[yak]]s live at elevations as high as {{convert|5400|m|ft mi|abbr=on}} above sea level; [[mountain goat]]s live up to {{convert|3050|m|ft mi|abbr=on}}. Herbivorous animals at these elevations depend on lichens, grasses, and herbs.

Life forms live in every part of the Earth's biosphere, including [[soil]], [[hot spring]]s, [[endolith|inside rocks]] at least {{convert|12|mi|km|order=flip|abbr=on}} deep underground, and at least {{convert|40|mi|km|order=flip|abbr=on}} high in the atmosphere.<ref name="SD-19980625-UG">{{cite web|publisher=University of Georgia|title=First-Ever Scientific Estimate of Total Bacteria on Earth Shows Far Greater Numbers Than Ever Known Before|url=https://www.sciencedaily.com/releases/1998/08/980825080732.htm|date=25 August 1998|work=[[Science Daily]]|access-date=10 November 2014|archive-url=https://web.archive.org/web/20141110162101/https://www.sciencedaily.com/releases/1998/08/980825080732.htm|archive-date=10 November 2014|url-status=live}}</ref><ref name="ABM-20150112">{{cite web|last=Hadhazy|first=Adam|title=Life Might Thrive a Dozen Miles Beneath Earth's Surface|url=http://www.astrobio.net/extreme-life/life-might-thrive-dozen-miles-beneath-earths-surface/|date=12 January 2015|work=[[Astrobiology Magazine]]|access-date=11 March 2017|archive-url=https://web.archive.org/web/20170312065614/http://www.astrobio.net/extreme-life/life-might-thrive-dozen-miles-beneath-earths-surface/|archive-date=12 March 2017|url-status=usurped}}</ref><ref name="BBC-20151124">{{cite web|last=Fox-Skelly|first=Jasmin|title=The Strange Beasts That Live in Solid Rock Deep Underground|url=http://www.bbc.com/earth/story/20151124-meet-the-strange-creatures-that-live-in-solid-rock-deep-underground|date=24 November 2015|publisher=[[BBC Online]]|access-date=11 March 2017|archive-url=https://web.archive.org/web/20161125013248/http://www.bbc.com/earth/story/20151124-meet-the-strange-creatures-that-live-in-solid-rock-deep-underground|archive-date=25 November 2016|url-status=live}}</ref> Marine life under many forms has been found in the deepest reaches of the [[world ocean]] while much of the [[deep sea]] remains to be explored.<ref>{{cite journal |last1=Briand |first1=F. |last2=Snelgrove |first2=P. |date=2003 |title=Mare Incognitum? An overview |journal=CIESM Workshop Monographs |volume=23 |pages=5–27}}[https://www.researchgate.net/publication/365871261]</ref>

Under certain test conditions, microorganisms have been observed to [[Panspermia#Research in outer space|survive the vacuum of outer space]].<ref name=Dose>{{cite journal|title=ERA-experiment "space biochemistry"|journal=Advances in Space Research|first1=K. Dose|author2=A. Bieger-Dose|author3=R. Dillmann|author4=M. Gill|author5=O. Kerz|others=A. Klein, H. Meinert, T. Nawroth, S. Risi, C. Stride|volume=16|issue=8|year=1995|pages=119–129|doi=10.1016/0273-1177(95)00280-R|last1=Zhang|pmid=11542696|bibcode=1995AdSpR..16h.119D}}</ref><ref name='Horneck'>{{cite journal|title=Biological responses to space: results of the experiment "Exobiological Unit" of ERA on EURECA I|journal=Adv. Space Res.|year=1995|author1=Horneck G|author2=Eschweiler U|author3=Reitz G|author4=Wehner J|author5=Willimek R|author6=Strauch K.|volume=16|issue=8|pages=105–18|pmid=11542695|bibcode=1995AdSpR..16h.105H|doi=10.1016/0273-1177(95)00279-N}}</ref> The total amount of soil and subsurface bacterial [[carbon]] is estimated as 5&nbsp;×&nbsp;10<sup>17</sup>&nbsp;g.<ref name="SD-19980625-UG" /> The mass of [[prokaryote]] microorganisms—which includes bacteria and archaea, but not the nucleated [[Microorganism#Eukaryotes|eukaryote microorganisms]]—may be as much as 0.8&nbsp;trillion tons of carbon (of the total biosphere [[Biomass (ecology)|mass]], estimated at between 1 and 4&nbsp;trillion tons).<ref name="AGCI-2014">{{cite web|author=Staff|title=The Biosphere|url=http://www.agci.org/classroom/biosphere/index.php|date=2014|publisher=[[The Given Institute|Aspen Global Change Institute]]|access-date=10 November 2014|archive-url=https://web.archive.org/web/20141110164609/http://www.agci.org/classroom/biosphere/index.php|archive-date=10 November 2014|url-status=live}}</ref> [[Piezophile|Barophilic]] marine microbes have been found at more than a depth of {{convert|10000|m|ft mi|abbr=on}} in the [[Mariana Trench]], the deepest spot in the Earth's oceans.<ref>{{cite journal|last1=Takamia|display-authors=etal|year=1997|title=Microbial flora in the deepest sea mud of the Mariana Trench|journal=FEMS Microbiology Letters|volume=152|issue=2|pages=279–285|doi=10.1111/j.1574-6968.1997.tb10440.x|pmid=9231422|doi-access=free}}</ref> In fact, single-celled life forms have been found in the deepest part of the Mariana Trench, by the [[Challenger Deep]], at depths of {{convert|11034|m|ft mi|abbr=on}}.<ref>{{Cite web|url=http://news.nationalgeographic.com/news/2005/02/0203_050203_deepest.html|title=National Geographic, 2005|access-date=2012-12-18|archive-url=https://web.archive.org/web/20120822121902/http://news.nationalgeographic.com/news/2005/02/0203_050203_deepest.html|archive-date=2012-08-22|url-status=dead}}</ref><ref name="LS-20130317">{{cite web|last=Choi|first=Charles Q.|title=Microbes Thrive in Deepest Spot on Earth|url=http://www.livescience.com/27954-microbes-mariana-trench.html|date=17 March 2013|publisher=[[LiveScience]]|access-date=17 March 2013|archive-url=https://web.archive.org/web/20130402234623/http://www.livescience.com/27954-microbes-mariana-trench.html|archive-date=2 April 2013|url-status=live}}</ref><ref name="NG-20130317">{{cite journal|last1=Glud|first1=Ronnie|last2=Wenzhöfer|first2=Frank|last3=Middelboe|first3=Mathias|last4=Oguri|first4=Kazumasa|last5=Turnewitsch|first5=Robert|last6=Canfield|first6=Donald E.|last7=Kitazato|first7=Hiroshi|title=High rates of microbial carbon turnover in sediments in the deepest oceanic trench on Earth|doi=10.1038/ngeo1773|date=17 March 2013|journal=[[Nature Geoscience]]|volume=6|issue=4|pages=284–288|bibcode=2013NatGe...6..284G}}</ref> Other researchers reported related studies that microorganisms thrive inside rocks up to {{convert|580|m|ft mi|abbr=on}} below the sea floor under {{convert|2590|m|ft mi|abbr=on}} of ocean off the coast of the [[northwestern United States]],<ref name="LS-20130317" /><ref name="LS-20130314">{{cite web|last=Oskin|first=Becky|title=Intraterrestrials: Life Thrives in Ocean Floor|url=http://www.livescience.com/27899-ocean-subsurface-ecosystem-found.html|date=14 March 2013|publisher=[[LiveScience]]|access-date=17 March 2013|archive-url=https://web.archive.org/web/20130402235647/http://www.livescience.com/27899-ocean-subsurface-ecosystem-found.html|archive-date=2 April 2013|url-status=live}}</ref> as well as {{convert|2400|m|ft mi|abbr=on}} beneath the seabed off Japan.<ref name="BBC-20141215-RM">{{cite news|last=Morelle|first=Rebecca|author-link=Rebecca Morelle|title=Microbes discovered by deepest marine drill analysed|url=https://www.bbc.com/news/science-environment-30489814|date=15 December 2014|publisher=BBC News|access-date=15 December 2014|archive-url=https://web.archive.org/web/20141216185424/http://www.bbc.com/news/science-environment-30489814|archive-date=16 December 2014|url-status=live}}</ref> Culturable thermophilic microbes have been extracted from cores drilled more than {{convert|5000|m|ft mi|abbr=on}} into the [[Earth's crust]] in [[Sweden]],<ref name="Szewzyketal1994">{{cite journal|last1=Szewzyk|first1=U|last2=Szewzyk|first2=R|last3=Stenstrom|first3=TR.|year=1994|title=Thermophilic, anaerobic bacteria isolated from a deep borehole in granite in Sweden|journal=Proceedings of the National Academy of Sciences of the USA|volume=91|issue=5|pages=1810–1813|doi=10.1073/pnas.91.5.1810|pmid=11607462|pmc=43253|bibcode=1994PNAS...91.1810S|doi-access=free}}</ref> from rocks between {{convert|65-75|°C|°F|abbr=on}}. Temperature [[geothermal gradient|increases with increasing depth]] into the Earth's crust. The rate at which the temperature increases depends on many factors, including the type of crust (continental vs. oceanic), rock type, geographic location, etc. The greatest known temperature at which microbial life can exist is {{convert|122|°C|°F|abbr=on}} (''[[Methanopyrus kandleri]]'' Strain 116). It is likely that the limit of life in the "[[deep biosphere]]" is defined by temperature rather than absolute depth.{{citation needed|date=January 2016}} On 20 August 2014, scientists confirmed the existence of microorganisms living {{convert|800|m|ft mi|abbr=on}} below the ice of [[Antarctica]].<ref name="NAT-20140820">{{cite journal|last=Fox|first=Douglas|title=Lakes under the ice: Antarctica's secret garden|date=20 August 2014|journal=[[Nature (journal)|Nature]]|volume=512|issue=7514|pages=244–246|doi=10.1038/512244a|bibcode=2014Natur.512..244F|pmid=25143097|doi-access=free}}</ref><ref name="FRB-20140820">{{cite web|last=Mack|first=Eric|title=Life Confirmed Under Antarctic Ice; Is Space Next?|url=https://www.forbes.com/sites/ericmack/2014/08/20/life-confirmed-under-antarctic-ice-is-space-next/|date=20 August 2014|work=[[Forbes]]|access-date=21 August 2014|archive-url=https://web.archive.org/web/20140822002442/http://www.forbes.com/sites/ericmack/2014/08/20/life-confirmed-under-antarctic-ice-is-space-next/|archive-date=22 August 2014|url-status=live}}</ref>

Earth's biosphere is divided into several [[biome]]s, inhabited by fairly similar [[flora (plants)|flora]] and [[fauna (animals)|fauna]]. On land, biomes are separated primarily by [[latitude]]. Terrestrial biomes lying within the [[Arctic Circle|Arctic]] and [[Antarctic Circle]]s are relatively barren of [[plant]] and [[animal]] life. In contrast, most of the more populous biomes lie near the [[equator]]. <!---Terrestrial organisms in temperate and Arctic biomes have relatively small amounts of total biomass, smaller energy requirements, and display prominent adaptations to cold, including world-spanning migrations, social adaptations, [[homeothermy]], [[estivation]] and multiple layers of insulation.--->