Editing Extremophile (section)

==Characteristics==
[[File:Diversity of extreme environments on Earth.jpg|thumb|upright=1.5| {{center|'''Diversity of extreme environments on Earth'''{{hsp}}<ref name="Merino2019">{{Cite journal |last1=Merino |first1=Nancy |last2=Aronson |first2=Heidi S. |last3=Bojanova |first3=Diana P. |last4=Feyhl-Buska |first4=Jayme |last5=Wong |first5=Michael L. |last6=Zhang |first6=Shu |last7=Giovannelli |first7=Donato |year=2019 |title=Living at the Extremes: Extremophiles and the Limits of Life in a Planetary Context |journal=Frontiers in Microbiology |volume=10 |page=780 |doi=10.3389/fmicb.2019.00780 |pmc=6476344 |pmid=31037068 |doi-access=free|bibcode=2019FrMic..10..780M }} [[File:CC-BY icon.svg|50px]] Material was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref>}}]]

In the 1980s and 1990s, biologists found that [[microbial life]] can survive in extreme environments—niches that are acidic, extraordinarily hot, or with irregular air pressure for example—that would be inhospitable to [[Multicellular organism|complex organisms]]. Some scientists even concluded that life may have begun on Earth in [[hydrothermal vent]]s far beneath the ocean's surface.<ref>{{Cite web |date=June 2003 |title=Mars Exploration Rover Launches – Press kit |url=https://mars.jpl.nasa.gov/mer/newsroom/merlaunch.pdf |access-date=14 July 2009 |publisher=NASA}}</ref>

According to astrophysicist Steinn Sigurdsson, "There are viable [[Endospore|bacterial spores]] that have been found that are 40 million years old on Earth—and we know they're very hardened to [[radiation]]."<ref>{{Cite web |last=BBC Staff |date=23 August 2011 |title=Impacts 'more likely' to have spread life from Earth |url=https://www.bbc.co.uk/news/science-environment-14637109 |access-date=24 August 2011 |publisher=BBC}}</ref> Some [[bacteria]] were found living in the cold and dark in a lake buried a half-mile deep under the ice in [[Antarctica]],<ref name="NYT-20130206">{{Cite web |last=Gorman |first=James |name-list-style=vanc |date=6 February 2013 |title=Bacteria Found Deep Under Antarctic Ice, Scientists Say |url=https://www.nytimes.com/2013/02/07/science/living-bacteria-found-deep-under-antarctic-ice-scientists-say.html |url-access=limited |archive-url=https://ghostarchive.org/archive/20220101/https://www.nytimes.com/2013/02/07/science/living-bacteria-found-deep-under-antarctic-ice-scientists-say.html |archive-date=2022-01-01 |access-date=6 February 2013 |website=[[The New York Times]]}}{{cbignore}}</ref> and in the [[Mariana Trench|Marianas Trench]], the deepest place in Earth's oceans.<ref name="LS-20130317">{{Cite web |last=Choi |first=Charles Q. |name-list-style=vanc |date=17 March 2013 |title=Microbes Thrive in Deepest Spot on Earth |url=http://www.livescience.com/27954-microbes-mariana-trench.html |access-date=17 March 2013 |publisher=[[LiveScience]]}}</ref><ref name="NG-20130317">{{Cite journal |vauthors=Glud RN, Wenzhöfer F, Middelboe M, Oguri K, Turnewitsch R, Canfield DE, Kitazato H |date=17 March 2013 |title=High rates of microbial carbon turnover in sediments in the deepest oceanic trench on Earth |journal=[[Nature Geoscience]] |volume=6 |issue=4 |pages=284–88 |bibcode=2013NatGe...6..284G |doi=10.1038/ngeo1773}}</ref> Expeditions of the [[International Ocean Discovery Program]] found microorganisms in {{Cvt|120|C}} sediment that is {{Cvt|1.2|km}} below seafloor in the [[Nankai Trough]] [[subduction]] zone.<ref name=":0">{{Cite journal |last1=Heuer |first1=Verena B. |last2=Inagaki |first2=Fumio |last3=Morono |first3=Yuki |last4=Kubo |first4=Yusuke |last5=Spivack |first5=Arthur J. |last6=Viehweger |first6=Bernhard |last7=Treude |first7=Tina |last8=Beulig |first8=Felix |last9=Schubotz |first9=Florence |last10=Tonai |first10=Satoshi |last11=Bowden |first11=Stephen A. |date=2020-12-04 |title=Temperature limits to deep subseafloor life in the Nankai Trough subduction zone |url=https://www.science.org/doi/10.1126/science.abd7934 |journal=Science |language=en |volume=370 |issue=6521 |pages=1230–34 |bibcode=2020Sci...370.1230H |doi=10.1126/science.abd7934 |issn=0036-8075 |pmid=33273103 |hdl-access=free |hdl=2164/15700 |s2cid=227257205}}</ref><ref>{{Cite web |title=T-Limit of the Deep Biosphere off Muroto |url=https://www.jamstec.go.jp/chikyu/e/exp370/ |access-date=2021-03-08 |website=www.jamstec.go.jp}}</ref> Some microorganisms have been found thriving inside rocks up to {{convert|1900|ft}} below the sea floor under {{convert|8500|ft}} of ocean off the coast of the northwestern United States.<ref name="LS-20130317" /><ref name="LS-20130314">{{Cite web |last=Oskin |first=Becky |name-list-style=vanc |date=14 March 2013 |title=Intraterrestrials: Life Thrives in Ocean Floor |url=http://www.livescience.com/27899-ocean-subsurface-ecosystem-found.html |access-date=17 March 2013 |publisher=[[LiveScience]]}}</ref> According to one of the researchers, "You can find microbes everywhere—they're extremely adaptable to conditions, and survive wherever they are."<ref name="LS-20130317" /> A key to extremophile adaptation is their [[amino acid]] composition, affecting their [[protein folding]] ability under particular conditions.<ref name="Reed 2013">{{Cite journal |vauthors=Reed CJ, Lewis H, Trejo E, Winston V, Evilia C |date=2013 |title=Protein adaptations in archaeal extremophiles |journal=Archaea |volume=2013 |pages=373275 |doi=10.1155/2013/373275 |pmc=3787623 |pmid=24151449 |doi-access=free}}</ref> Studying extreme environments on Earth can help researchers understand the limits of habitability on other worlds.<ref name="NASA strategy 2015">{{Cite web |year=2015 |title=NASA Astrobiology Strategy |url=https://nai.nasa.gov/media/medialibrary/2015/10/NASA_Astrobiology_Strategy_2015_151008.pdf |url-status=dead |archive-url=https://web.archive.org/web/20161222190306/https://nai.nasa.gov/media/medialibrary/2015/10/NASA_Astrobiology_Strategy_2015_151008.pdf |archive-date=22 December 2016 |access-date=12 October 2017 |website=NASA |pages=59}}</ref>

Tom Gheysens from Ghent University in Belgium and colleagues showed that [[endospores]] from a species of ''Bacillus'' bacteria were viable after being heated to temperatures of {{convert|420|C}}.<ref>{{Cite web|url=https://www.smithsonianmag.com/air-space-magazine/turn-heat-bacterial-spores-can-take-temperatures-hundreds-degrees-180970425/|title=Turn Up the Heat: Bacterial Spores Can Take Temperatures in the Hundreds of Degrees|first1=Smithsonian|last1=Magazine|first2=Dirk|last2=Schulze-Makuch|website=Smithsonian Magazine}}</ref>