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{{Short description|Material world and its phenomena}} |
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{{Other uses}} |
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{{Redirect|Natural|other uses|Natural (disambiguation)|and|Nature (disambiguation)}} |
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{{short description|Natural physical or material world}} |
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[[File:Startrails above Gunung Bromo - Indonesia.jpg|upright=1.3|thumb|A timelapse composite panorama of different natural phenomena and environments around [[Mount Bromo]], Indonesia.]] |
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'''Nature''' is an inherent character or constitution,<ref name="Merriam-Webster 2024 d901">{{cite web | title=Definition of NATURE | website=Merriam-Webster | date=January 2, 2024 | url=https://www.merriam-webster.com/dictionary/nature | access-date=January 7, 2024 | archive-date=January 2, 2024 | archive-url=https://web.archive.org/web/20240102145752/https://www.merriam-webster.com/dictionary/nature | url-status=live }}</ref> particularly of the [[Ecosphere (planetary)|ecosphere]] or the [[universe]] as a whole. In this general sense nature refers to the [[Scientific law|laws]], elements and [[phenomenon|phenomena]] of the physical world, including [[life]]. Although humans are part of nature, human activity or humans as a whole are often described as at times at odds, or outright [[Anthropocentrism|separate and even superior]] to nature.<ref name="What does nature mean"/> |
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| image1 = Shaqi_jrvej.jpg |
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| caption1 = [[Shaki Waterfall]], Armenia |
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| image2 = Bachalpsee reflection.jpg |
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| caption2 = [[Bachalpsee]] in the [[Swiss Alps]] |
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| image3 = Galunggung.jpg |
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| caption3 = [[Lightning]] strikes during the eruption of the [[Galunggung]] [[volcano]], [[West Java]], in 1982 |
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| image4 = Expn7398 (39695069782).jpg |
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| caption4 = Life in the abyssal oceans |
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During the advent of modern [[scientific method]] in the last several centuries, nature became the passive [[reality]], organized and moved by divine laws.<ref>Isaac Newton's [[Philosophiae Naturalis Principia Mathematica]] (1687), for example, is translated "Mathematical Principles of Natural Philosophy", and reflects the then-current use of the words "[[natural philosophy]]", akin to "systematic study of nature"</ref><ref>The etymology of the word "physical" shows its use as a synonym for "natural" in about the mid-15th century: {{OEtymD|physical|access-date=September 20, 2006}}</ref> With the [[Industrial Revolution]], nature increasingly became seen as the part of reality deprived from intentional intervention: it was hence considered as sacred by some traditions ([[Jean-Jacques Rousseau|Rousseau]], American [[transcendentalism]]) or a mere decorum for [[divine providence]] or human history ([[Hegel]], [[Marx]]). However, a [[vitalist]] vision of nature, closer to the pre-Socratic one, got reborn at the same time, especially after [[Charles Darwin]].<ref name="What does nature mean" /> |
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'''Nature''', in the broadest sense, is the natural, physical, or material world or [[universe]]. "Nature" can refer to the [[phenomenon|phenomena]] of the physical world, and also to life in general. The study of nature is a large, if not the only, part of [[science]]. Although humans are part of nature, human activity is often understood as a separate category from other natural phenomena.<ref name="What does nature mean"/> |
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Within the various uses of the word today, "nature" often refers to [[geology]] and [[wildlife]]. Nature can refer to the general realm of [[life|living beings]], and in some cases to the processes associated with inanimate objects—the way that particular types of things exist and change of their own accord, such as the weather and geology of the [[Earth]]. It is often taken to mean the "[[natural environment]]" or [[wilderness]]—wild animals, rocks, forest, and in general those things that have not been substantially altered by human intervention, or which persist despite human intervention. For example, manufactured objects and human interaction generally are not considered part of nature, unless qualified as, for example, "human nature" or "the whole of nature". This more traditional concept of natural things that can still be found today implies a distinction between the natural and the artificial, with the artificial being understood as that which has been brought into being by a human [[consciousness]] or a human [[mind]]. Depending on the particular context, the term "natural" might also be distinguished from the [[Wikt:unnatural|unnatural]] or the [[supernatural]].<ref name="What does nature mean"/> |
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The word ''nature'' is derived from the [[Latin]] word ''natura'', or "essential qualities, innate disposition", and in ancient times, literally meant "birth".<ref name="etymonline-nature">{{OEtymD|nature|accessdate=September 23, 2006}}</ref> In ancient philosophy, ''Natura'' is mostly used as the Latin translation of the Greek word ''[[physis]]'' (φύσις), which originally related to the intrinsic characteristics that plants, animals, and other features of the world develop of their own accord.<ref>An account of the pre-Socratic use of the concept of φύσις may be found in Naddaf, Gerard (2006) ''The Greek Concept of Nature'', SUNY Press, and in {{cite journal |last1=Ducarme |first1=Frédéric |last2=Couvet |first2=Denis |year=2020 |title=What does 'nature' mean? |journal=[[Palgrave Communications]] |volume=6 |issue=14 |publisher=[[Springer Nature]] |pages= |doi=10.1057/s41599-020-0390-y }}. The word φύσις, while first used in connection with a plant in Homer, occurs very early in Greek philosophy, and in several senses. Generally, these senses match rather well the current senses in which the English word ''nature'' is used, as confirmed by Guthrie, W.K.C. ''Presocratic Tradition from Parmenides to Democritus'' (volume 2 of his ''History of Greek Philosophy''), Cambridge UP, 1965.</ref><ref>The first known use of ''physis'' was by [[Homer]] in reference to the intrinsic qualities of a plant: ὣς ἄρα φωνήσας πόρε φάρμακον ἀργεϊφόντης ἐκ γαίης ἐρύσας, καί μοι '''φύσιν''' αὐτοῦ ἔδειξε. (So saying, Argeiphontes [=Hermes] gave me the herb, drawing it from the ground, and showed me its '''nature'''.) ''[[Odyssey]]'' 10.302–03 (ed. A.T. Murray). (The word is dealt with thoroughly in Liddell and Scott's ''[http://archimedes.fas.harvard.edu/pollux Greek Lexicon] {{Webarchive|url=https://web.archive.org/web/20110305235638/http://archimedes.fas.harvard.edu/pollux/ |date=March 5, 2011 }}''.) For later but still very early Greek uses of the term, see earlier note.</ref> |
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The concept of nature as a whole, the physical [[universe]], is one of several expansions of the original notion;<ref name="What does nature mean">{{cite journal |last1=Ducarme |first1=Frédéric |last2=Couvet |first2=Denis |year=2020 |title=What does 'nature' mean? |journal=[[Palgrave Communications]] |volume=6 |issue=14 |publisher=[[Springer Nature]] |pages= |doi=10.1057/s41599-020-0390-y }}</ref> it began with certain core applications of the word φύσις by [[Pre-Socratic philosophy|pre-Socratic]] philosophers (though this word had a dynamic dimension then, especially for [[Heraclitus]]), and has steadily gained currency ever since. During the advent of modern [[scientific method]] in the last several centuries, nature became the passive reality, organized and moved by divine laws.<ref>Isaac Newton's [[Philosophiae Naturalis Principia Mathematica]] (1687), for example, is translated "Mathematical Principles of Natural Philosophy", and reflects the then-current use of the words "[[natural philosophy]]", akin to "systematic study of nature"</ref><ref>The etymology of the word "physical" shows its use as a synonym for "natural" in about the mid-15th century: {{OEtymD|physical|accessdate=September 20, 2006}}</ref> With the [[Industrial revolution]], nature increasingly became seen as the part of reality deprived from intentional intervention : it was hence considered as sacred by some traditions ([[Jean-Jacques Rousseau|Rousseau]], American [[transcendentalism]]) or a mere decorum for divine providence or human history ([[Hegel]], [[Marx]]). However, a vitalist vision of nature, closer to the presocratic one, got reborn at the same time, especially after [[Charles Darwin]].<ref name="What does nature mean"/> |
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==Etymology== |
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Within the various uses of the word today, "nature" often refers to geology and [[wildlife]]. Nature can refer to the general realm of living plants and animals, and in some cases to the processes associated with inanimate objects—the way that particular types of things exist and change of their own accord, such as the weather and geology of the [[Earth]]. It is often taken to mean the "[[natural environment]]" or [[wilderness]]—wild animals, rocks, forest, and in general those things that have not been substantially altered by human intervention, or which persist despite human intervention. For example, manufactured objects and human interaction generally are not considered part of nature, unless qualified as, for example, "human nature" or "the whole of nature". This more traditional concept of natural things that can still be found today implies a distinction between the natural and the artificial, with the artificial being understood as that which has been brought into being by a human [[consciousness]] or a human [[mind]]. Depending on the particular context, the term "natural" might also be distinguished from the [[Wikt:unnatural|unnatural]] or the [[supernatural]].<ref name="What does nature mean"/> |
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The word ''nature'' is borrowed from the [[Old French]] ''nature'' and is derived from the [[Latin]] word ''natura'', or "essential qualities, innate disposition", and in ancient times, literally meant "[[birth]]".<ref name="etymonline-nature">{{OEtymD|nature|access-date=September 23, 2006}}</ref> In ancient philosophy, ''natura'' is mostly used as the Latin translation of the Greek word ''[[physis]]'' (φύσις), which originally related to the intrinsic characteristics of plants, animals, and other features of the world to develop of their own accord.<ref>An account of the pre-Socratic use of the concept of φύσις may be found in Naddaf, Gerard (2006) ''The Greek Concept of Nature'', SUNY Press, and in {{cite journal |last1=Ducarme |first1=Frédéric |last2=Couvet |first2=Denis |year=2020 |title=What does 'nature' mean? |journal=[[Palgrave Communications]] |volume=6 |issue=14 |publisher=[[Springer Nature]] |doi=10.1057/s41599-020-0390-y |doi-access=free }}. The word φύσις, while first used in connection with a plant in Homer, occurs early in Greek philosophy, and in several senses. Generally, these senses match rather well the current senses in which the English word ''nature'' is used, as confirmed by Guthrie, W.K.C. ''Presocratic Tradition from Parmenides to Democritus'' (volume 2 of his ''History of Greek Philosophy''), Cambridge UP, 1965.</ref><ref>The first known use of ''physis'' was by [[Homer]] in reference to the intrinsic qualities of a plant: ὣς ἄρα φωνήσας πόρε φάρμακον ἀργεϊφόντης ἐκ γαίης ἐρύσας, καί μοι '''φύσιν''' αὐτοῦ ἔδειξε. (So saying, Argeiphontes [=Hermes] gave me the herb, drawing it from the ground, and showed me its '''nature'''.) ''[[Odyssey]]'' 10.302–303 (ed. A.T. Murray). (The word is dealt with thoroughly in Liddell and Scott's ''[http://archimedes.fas.harvard.edu/pollux Greek Lexicon] {{Webarchive|url=https://web.archive.org/web/20110305235638/http://archimedes.fas.harvard.edu/pollux/ |date=March 5, 2011 }}''.) For later but still very early Greek uses of the term, see earlier note.</ref> |
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The concept of nature as a whole, the physical [[universe]], is one of several expansions of the original notion;<ref name="What does nature mean">{{cite journal |last1=Ducarme |first1=Frédéric |last2=Couvet |first2=Denis |year=2020 |title=What does 'nature' mean? |journal=[[Palgrave Communications]] |volume=6 |issue=14 |publisher=[[Springer Nature]] |doi=10.1057/s41599-020-0390-y |doi-access=free }}</ref> it began with certain core applications of the word φύσις by [[Pre-Socratic philosophy|pre-Socratic]] philosophers (though this word had a dynamic dimension then, especially for [[Heraclitus]]), and has steadily gained currency ever since. |
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==Earth== |
==Earth== |
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{{Nature timeline}} |
{{Nature timeline}} |
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{{Main|Earth|Earth science}} |
{{Main|Earth|Earth science}} |
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[[File:The Earth seen from Apollo 17.jpg|thumb|left| |
[[File:The Earth seen from Apollo 17.jpg|thumb|left|''[[The Blue Marble]]'', which is a famous view of the [[Earth]], taken in 1972 by the crew of [[Apollo 17]]]] |
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Earth is the only [[planet]] known to support life, and its natural features are the subject of many fields of scientific research. Within the [[ |
Earth is the only [[planet]] known to support [[life]], and its natural features are the subject of many fields of scientific research. Within the [[Solar System]], it is third closest to the Sun; it is the largest [[terrestrial planet]] and the fifth largest overall. Its most prominent climatic features are its two large polar regions, two relatively narrow [[temperate]] zones, and a wide [[equator]]ial tropical to [[subtropical]] region.<ref> |
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{{cite web |
{{cite web |
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|url=http://www.blueplanetbiomes.org/climate.htm |
|url=http://www.blueplanetbiomes.org/climate.htm |
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|title=World Climates |
|title=World Climates |
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|work=Blue Planet Biomes |
|work=Blue Planet Biomes |
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|access-date=September 21, 2006 |
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|archive-url=https://web.archive.org/web/20081217015636/http://www.blueplanetbiomes.org/climate.htm |
|archive-url=https://web.archive.org/web/20081217015636/http://www.blueplanetbiomes.org/climate.htm |
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|archive-date=December 17, 2008 |
|archive-date=December 17, 2008 |
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</ref> [[ |
</ref> [[Precipitation]] varies widely with location, from several metres of water per year to less than a millimetre. 71 percent of the Earth's surface is covered by salt-water oceans. The remainder consists of continents and islands, with most of the inhabited land in the [[Northern Hemisphere]]. |
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Earth has evolved through geological and biological processes that have left traces of the original conditions. The [[Crust (geology)|outer surface]] is divided into several gradually migrating [[tectonic plate]]s. The interior remains active, with a thick layer of plastic [[Mantle (geology)|mantle]] and an iron-filled core that generates a [[magnetic field]]. This iron core is composed of a solid inner phase, and a fluid outer phase. Convective motion in the core generates electric currents through dynamo action, and these, in turn, generate the geomagnetic field. |
Earth has evolved through geological and biological processes that have left traces of the original conditions. The [[Crust (geology)|outer surface]] is divided into several gradually migrating [[tectonic plate]]s. The interior remains active, with a thick layer of plastic [[Mantle (geology)|mantle]] and an iron-filled core that generates a [[magnetic field]]. This iron core is composed of a solid inner phase, and a fluid outer phase. Convective motion in the core generates electric currents through dynamo action, and these, in turn, generate the geomagnetic field. |
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The [[atmosphere|atmospheric]] conditions have been significantly altered from the original conditions by the presence of life-forms,<ref>{{cite web|date = September 11, 2005|url = https://www.sciencedaily.com/releases/2005/09/050911103921.htm|title = Calculations favor reducing atmosphere for early Earth|work = [[Science Daily]]| |
The [[atmosphere|atmospheric]] conditions have been significantly altered from the original conditions by the presence of life-forms,<ref>{{cite web|date = September 11, 2005|url = https://www.sciencedaily.com/releases/2005/09/050911103921.htm|title = Calculations favor reducing atmosphere for early Earth|work = [[Science Daily]]|access-date = January 6, 2007|archive-url = https://web.archive.org/web/20060830150624/http://www.sciencedaily.com/releases/2005/09/050911103921.htm|archive-date = August 30, 2006|url-status=live|df = mdy-all}}</ref> which create an ecological balance that stabilizes the surface conditions. Despite the wide regional variations in climate by [[latitude]] and other geographic factors, the long-term average global climate is quite stable during interglacial periods,<ref>{{cite web|url = http://www.epa.gov/climatechange/science/pastcc.html|title = Past Climate Change| date=October 19, 2006 |publisher = U.S. Environmental Protection Agency|access-date = January 7, 2007|archive-url = https://web.archive.org/web/20120511021842/http://www.epa.gov/climatechange/science/pastcc.html|archive-date = May 11, 2012|url-status=live|df = mdy-all}}</ref> and variations of a degree or two of average global temperature have historically had major effects on the ecological balance, and on the actual geography of the Earth.<ref>{{cite web|author = Hugh Anderson|author2 = Bernard Walter|date = March 28, 1997|url = http://vathena.arc.nasa.gov/curric/land/global/climchng.html|title = History of Climate Change|publisher = NASA|access-date = January 7, 2007|url-status = dead|archive-url = https://web.archive.org/web/20080123130745/http://vathena.arc.nasa.gov/curric/land/global/climchng.html|archive-date = January 23, 2008}}</ref><ref>{{cite web|last = Weart|first = Spencer|date = June 2006|url = http://www.aip.org/history/climate/|title = The Discovery of Global Warming|publisher = American Institute of Physics|access-date = January 7, 2007|archive-url = https://web.archive.org/web/20110804232058/http://www.aip.org/history/climate/|archive-date = August 4, 2011|url-status = dead|df = mdy-all}}</ref> |
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===Geology=== |
===Geology=== |
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{{Main|Geology}} |
{{Main|Geology}} |
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Geology is the science and study of the solid and liquid matter that constitutes the |
Geology is the science and study of the solid and liquid matter that constitutes the Earth. The field of geology encompasses the study of the composition, [[structural geology|structure]], [[Physical property|physical properties]], dynamics, and [[History of the Earth|history]] of [[Earth materials]], and the processes by which they are formed, moved, and changed. The field is a major [[academic discipline]], and is also important for [[mining|mineral]] and [[petroleum geology|hydrocarbon]] extraction, knowledge about and mitigation of [[natural hazard]]s, some [[Geotechnical engineering]] fields, and understanding [[Paleoclimatology|past climates]] and environments. |
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====Geological evolution==== |
====Geological evolution==== |
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[[File:Tectonic plate boundaries.png|thumb|left|upright=1.3|Three types of geological [[plate tectonic]] boundaries |
[[File:Tectonic plate boundaries.png|thumb|left|upright=1.3|Three types of geological [[plate tectonic]] boundaries]] |
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The geology of an area evolves through time as rock units are deposited and inserted and deformational processes change their shapes and locations. |
The geology of an area evolves through time as rock units are deposited and inserted and deformational processes change their shapes and locations. |
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===Historical perspective=== |
===Historical perspective=== |
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{{Main|History of the Earth|Evolution}} |
{{Main|History of the Earth|Evolution}} |
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[[File:Pangea animation 03.gif|thumb|300px|An animation showing the movement of the continents from the separation of [[Pangaea]] until the present day |
[[File:Pangea animation 03.gif|thumb|300px|An animation showing the movement of the continents from the separation of [[Pangaea]] until the present day]] |
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Earth is estimated to have formed 4.54 billion years ago from the [[solar nebula]], along with the [[Sun]] and other [[planet]]s.<ref>{{cite book |first=G. Brent |last=Dalrymple |date=1991 |title=The Age of the Earth |publisher=Stanford University Press |location=Stanford |isbn=978-0-8047-1569-0}}</ref> The |
Earth is estimated to have formed 4.54 billion years ago from the [[solar nebula]], along with the [[Sun]] and other [[planet]]s.<ref>{{cite book |first=G. Brent |last=Dalrymple |date=1991 |title=The Age of the Earth |publisher=Stanford University Press |location=Stanford |isbn=978-0-8047-1569-0}}</ref> The Moon formed roughly 20 million years later. Initially molten, the outer layer of the Earth cooled, resulting in the solid crust. Outgassing and [[Volcano|volcanic]] activity produced the primordial atmosphere. Condensing [[water vapor]], most or all of which came from [[ice]] delivered by [[comet]]s, [[Origin of water on Earth|produced the oceans]] and other water sources.<ref> |
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{{cite journal|first=A.|last=Morbidelli|display-authors=etal|date=2000|bibcode=2000M&PS...35.1309M|title=Source Regions and Time Scales for the Delivery of Water to Earth|journal=Meteoritics & Planetary Science|volume=35|issue=6|pages=1309–1320|doi=10.1111/j.1945-5100.2000.tb01518.x|doi-access=free}}</ref> The highly energetic chemistry is believed to have produced a self-replicating molecule around 4 billion years ago.<ref>{{cite news|title=Earth's Oldest Mineral Grains Suggest an Early Start for Life|publisher=NASA Astrobiology Institute|date=December 24, 2001|url=http://nai.arc.nasa.gov/news_stories/news_detail.cfm?ID=76|access-date=May 24, 2006|url-status=dead|archive-url=https://web.archive.org/web/20060928231649/http://nai.arc.nasa.gov/news_stories/news_detail.cfm?ID=76|archive-date=September 28, 2006}}</ref> |
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{{cite journal |
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[[File:Hyperia.jpg|thumb|left|[[Plankton]] inhabit oceans, seas and lakes, and have existed in various forms for at least 2 billion years.<ref name="Margulis1995">{{cite book|last=Margulis|first=Lynn|author-link=Lynn Margulis|author2=Dorian Sagan|date=1995|title=What is Life?|publisher=Simon & Schuster|location=New York|isbn=978-0-684-81326-4|url=https://archive.org/details/isbn_9780684810874}}</ref>]] |
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|first=A. |
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Continents formed, then broke up and reformed as the surface of Earth reshaped over hundreds of millions of years, occasionally combining to make a [[supercontinent]]. Roughly 750 million years ago, the earliest known supercontinent [[Rodinia]], began to break apart. The continents later recombined to form [[Pannotia]] which broke apart about 540 million years ago, then finally [[Pangaea]], which broke apart about 180 million years ago.<ref>{{cite journal |first=J.B. |last=Murphy |author2=R.D. Nance |date=2004 |url=http://www.americanscientist.org/issues/page2/how-do-supercontinents-assemble |title=How do supercontinents assemble? |journal=American Scientist |volume=92 |issue=4 |doi=10.1511/2004.4.324 |page=324 |access-date=August 23, 2010 |archive-url=https://web.archive.org/web/20110128224011/http://www.americanscientist.org/issues/page2/how-do-supercontinents-assemble |archive-date=January 28, 2011 |url-status=dead |df=mdy-all }}</ref> |
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|last=Morbidelli |
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|display-authors=etal |
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|date=2000 |
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|bibcode=2000M&PS...35.1309M |
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|title=Source Regions and Time Scales for the Delivery of Water to Earth |
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|journal=Meteoritics & Planetary Science |
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|volume=35 |
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|issue=6 |
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|pages=1309–20 |
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|doi=10.1111/j.1945-5100.2000.tb01518.x |
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}}</ref> The highly energetic chemistry is believed to have produced a self-replicating molecule around 4 billion years ago.<ref> |
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{{cite news |
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|title=Earth's Oldest Mineral Grains Suggest an Early Start for Life |
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|publisher=NASA Astrobiology Institute |
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|date=December 24, 2001 |
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|url=http://nai.arc.nasa.gov/news_stories/news_detail.cfm?ID=76 |
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|accessdate=May 24, 2006 |
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|url-status=dead |
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|archiveurl=https://web.archive.org/web/20060928231649/http://nai.arc.nasa.gov/news_stories/news_detail.cfm?ID=76 |
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|archivedate=September 28, 2006 |
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During the [[Neoproterozoic]] era, freezing temperatures covered much of the Earth in [[glacier]]s and ice sheets. This hypothesis has been termed the "[[Snowball Earth]]", and it is of particular interest as it precedes the [[Cambrian explosion]] in which multicellular life forms began to proliferate about 530–540 million years ago.<ref>{{cite book |first=J.L. |last=Kirschvink |date=1992 |chapter=Late Proterozoic Low-Latitude Global Glaciation: The Snowball Earth |chapter-url=http://www.gps.caltech.edu/~jkirschvink/pdfs/firstsnowball.pdf |title=The Proterozoic Biosphere |editor=J.W. Schopf |editor2=C. Klein |publisher=Cambridge University Press |location=Cambridge |pages=51–52 |isbn=978-0-521-36615-1 |access-date=September 22, 2006 |archive-date=September 9, 2014 |archive-url=https://web.archive.org/web/20140909194300/http://www.gps.caltech.edu/~jkirschvink/pdfs/firstsnowball.pdf |url-status=live }}</ref> |
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}}</ref> |
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[[File:Hyperia.jpg|thumb|left|[[Plankton]] inhabit oceans, seas and lakes, and have existed in various forms for at least 2 billion years.<ref name="Margulis1995">{{cite book|last=Margulis|first=Lynn|author2=Dorian Sagan|date=1995|title=What is Life?|publisher=Simon & Schuster|location=New York|isbn=978-0-684-81326-4|url=https://archive.org/details/isbn_9780684810874}}</ref>]] |
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Continents formed, then broke up and reformed as the surface of Earth reshaped over hundreds of millions of years, occasionally combining to make a [[supercontinent]]. Roughly 750 million years ago, the earliest known supercontinent [[Rodinia]], began to break apart. The continents later recombined to form [[Pannotia]] which broke apart about 540 million years ago, then finally [[Pangaea]], which broke apart about 180 million years ago.<ref>{{cite journal |first=J.B. |last=Murphy |author2=R.D. Nance |date=2004 |url=http://www.americanscientist.org/issues/page2/how-do-supercontinents-assemble |title=How do supercontinents assemble? |journal=American Scientist |volume=92 |issue=4 |doi=10.1511/2004.4.324 |page=324 |access-date=August 23, 2010 |archive-url=https://web.archive.org/web/20110128224011/http://www.americanscientist.org/issues/page2/how-do-supercontinents-assemble |archive-date=January 28, 2011 |url-status=live |df=mdy-all }}</ref> |
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Since the Cambrian explosion there have been five distinctly identifiable [[Extinction event|mass extinctions]].<ref>{{cite journal |last=Raup |first=David M. |author2=J. John Sepkoski Jr. |date=March 1982 |title=Mass extinctions in the marine fossil record |journal=Science |volume=215 |issue=4539|pages = 1501–1503 |doi=10.1126/science.215.4539.1501 |pmid=17788674 |bibcode=1982Sci...215.1501R|s2cid=43002817 }}</ref> The last mass extinction occurred some 66 million years ago, when a meteorite collision probably triggered the extinction of the [[Bird|non-avian]] [[dinosaur]]s and other large reptiles, but spared small animals such as [[mammal]]s. Over the past 66 million years, mammalian life diversified.<ref>{{cite book |last=Margulis |first=Lynn |author2=Dorian Sagan |date=1995 |title=What is Life? |publisher=Simon & Schuster |location=New York |isbn=978-0-684-81326-4 |page=[https://archive.org/details/isbn_9780684810874/page/145 145] |url=https://archive.org/details/isbn_9780684810874/page/145 }}</ref> |
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During the [[Neoproterozoic]] era, freezing temperatures covered much of the Earth in [[glacier]]s and ice sheets. This hypothesis has been termed the "[[Snowball Earth]]", and it is of particular interest as it precedes the [[Cambrian explosion]] in which multicellular life forms began to proliferate about 530–540 million years ago.<ref>{{cite book |first=J.L. |last=Kirschvink |date=1992 |chapter=Late Proterozoic Low-Latitude Global Glaciation: The Snowball Earth |chapterurl=http://www.gps.caltech.edu/~jkirschvink/pdfs/firstsnowball.pdf |title=The Proterozoic Biosphere |editor=J.W. Schopf |editor2=C. Klein |publisher=Cambridge University Press |location=Cambridge |pages=51–52 |isbn=978-0-521-36615-1}}</ref> |
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Since the Cambrian explosion there have been five distinctly identifiable [[Extinction event|mass extinctions]].<ref>{{cite journal |last=Raup |first=David M. |author2=J. John Sepkoski Jr. |date=March 1982 |title=Mass extinctions in the marine fossil record |journal=Science |volume=215 |issue=4539|pages = 1501–03 |doi=10.1126/science.215.4539.1501 |pmid=17788674 |bibcode=1982Sci...215.1501R|url=https://semanticscholar.org/paper/9442a415ed7dec89a6294a4a449ec6500dc6f9a3 }}</ref> The last mass extinction occurred some 66 million years ago, when a meteorite collision probably triggered the extinction of the [[Bird|non-avian]] [[dinosaur]]s and other large reptiles, but spared small animals such as [[mammal]]s. Over the past 66 million years, mammalian life diversified.<ref>{{cite book |last=Margulis |first=Lynn |author2=Dorian Sagan |date=1995 |title=What is Life? |publisher=Simon & Schuster |location=New York |isbn=978-0-684-81326-4 |page=[https://archive.org/details/isbn_9780684810874/page/145 145] |url=https://archive.org/details/isbn_9780684810874/page/145 }}</ref> |
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Several million years ago, a species of small African [[ape]] gained the ability to stand upright.<ref name="Margulis1995" /> The subsequent advent of human life, and the development of agriculture and further [[civilization]] allowed humans to affect the Earth more rapidly than any previous life form, affecting both the nature and quantity of other organisms as well as global climate. By comparison, the [[Great Oxygenation Event]], produced by the proliferation of [[algae]] during the [[Siderian]] period, required about 300 million years to culminate. |
Several million years ago, a species of small African [[ape]] gained the ability to stand upright.<ref name="Margulis1995" /> The subsequent advent of human life, and the development of agriculture and further [[civilization]] allowed humans to affect the Earth more rapidly than any previous life form, affecting both the nature and quantity of other organisms as well as global climate. By comparison, the [[Great Oxygenation Event]], produced by the proliferation of [[algae]] during the [[Siderian]] period, required about 300 million years to culminate. |
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The present era is classified as part of a mass [[extinction event]], the [[Holocene extinction]] event, the fastest ever to have occurred.<ref>{{cite journal|author = Diamond J|title = The present, past and future of human-caused extinctions|journal = Philos Trans R Soc Lond B Biol Sci|volume = 325|issue = 1228|pages = |
The present era is classified as part of a mass [[extinction event]], the [[Holocene extinction]] event, the fastest ever to have occurred.<ref>{{cite journal|author = Diamond J|title = The present, past and future of human-caused extinctions|journal = Philos Trans R Soc Lond B Biol Sci|volume = 325|issue = 1228|pages = 469–476; discussion 476–477|date = 1989|pmid = 2574887|doi = 10.1098/rstb.1989.0100|last2 = Ashmole|first2 = N. P.|last3 = Purves|first3 = P. E.|bibcode = 1989RSPTB.325..469D|doi-access = }}</ref><ref>{{cite journal|author = Novacek M|author2 = Cleland E|title = The current biodiversity extinction event: scenarios for mitigation and recovery|journal = Proc Natl Acad Sci USA|volume = 98|issue = 10|date = 2001|pmid = 11344295|doi = 10.1073/pnas.091093698|pmc = 33235|bibcode = 2001PNAS...98.5466N|pages = 5466–5470|doi-access = free}}</ref> Some, such as [[E. O. Wilson]] of [[Harvard University]], predict that human destruction of the [[biosphere]] could cause the extinction of one-half of all species in the next 100 years.<ref>{{cite journal|title=The mid-Holocene extinction of silver fir (Abies alba) in the Southern Alps: a consequence of forest fires? Palaeobotanical records and forest simulations|doi=10.1007/s00334-006-0051-0|date=2006|last1=Wick|first1=Lucia|last2=Möhl|first2=Adrian|journal=Vegetation History and Archaeobotany|volume=15|issue=4|pages=435–444|bibcode=2006VegHA..15..435W |s2cid=52953180|url=http://doc.rero.ch/record/309852/files/334_2006_Article_51.pdf|access-date=November 15, 2018|archive-url=https://web.archive.org/web/20181115113137/http://doc.rero.ch/record/309852/files/334_2006_Article_51.pdf|archive-date=November 15, 2018|url-status=live|df=mdy-all}}</ref> The extent of the current extinction event is still being researched, debated and calculated by biologists.<ref>[http://park.org/Canada/Museum/extinction/holmass.html The Holocene Extinction] {{Webarchive|url=https://web.archive.org/web/20060925041056/http://park.org/Canada/Museum/extinction/holmass.html |date=September 25, 2006 }}. Park.org. Retrieved on November 3, 2016.</ref><ref>[http://park.org/Canada/Museum/extinction/extincmenu.html Mass Extinctions Of The Phanerozoic Menu] {{Webarchive|url=https://web.archive.org/web/20060925030659/http://park.org/Canada/Museum/extinction/extincmenu.html |date=September 25, 2006 }}. Park.org. Retrieved on November 3, 2016.</ref><ref>[http://park.org/Canada/Museum/extinction/patterns.html Patterns of Extinction] {{Webarchive|url=https://web.archive.org/web/20060925024739/http://park.org/Canada/Museum/extinction/patterns.html |date=September 25, 2006 }}. Park.org. Retrieved on November 3, 2016.</ref> |
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{{clear right}} |
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==Atmosphere, climate, and weather== |
==Atmosphere, climate, and weather== |
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[[File:Top of Atmosphere.jpg|thumb|[[Rayleigh scattering|Blue light is scattered more]] than other wavelengths by the gases in the [[atmosphere]], giving the Earth a blue [[Halo (optical phenomenon)|halo]] when seen from space]] |
[[File:Top of Atmosphere.jpg|thumb|[[Rayleigh scattering|Blue light is scattered more]] than other wavelengths by the gases in the [[atmosphere]], giving the Earth a blue [[Halo (optical phenomenon)|halo]] when seen from space.]] |
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{{Main|Atmosphere of Earth|Climate|Weather}} |
{{Main|Atmosphere of Earth|Climate|Weather}} |
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The Earth's atmosphere is a key factor in sustaining the [[Nature#Ecosystems|ecosystem]]. The thin layer of gases that envelops the Earth is held in place by gravity. Air is mostly [[nitrogen]], [[oxygen]], [[water vapor]], with much smaller amounts of carbon dioxide, argon, etc. The atmospheric pressure declines steadily with altitude. The [[ozone layer]] plays an important role in depleting the amount of [[ultraviolet]] (UV) radiation that reaches the surface. As [[DNA]] is readily damaged by UV light, this serves to protect life at the surface. The atmosphere also retains heat during the night, thereby reducing the daily temperature extremes. |
The Earth's atmosphere is a key factor in sustaining the [[Nature#Ecosystems|ecosystem]]. The thin layer of gases that envelops the Earth is held in place by gravity. Air is mostly [[nitrogen]], [[oxygen]], [[water vapor]], with much smaller amounts of carbon dioxide, argon, etc. The atmospheric pressure declines steadily with altitude. The [[ozone layer]] plays an important role in depleting the amount of [[ultraviolet]] (UV) radiation that reaches the surface. As [[DNA]] is readily damaged by UV light, this serves to protect life at the surface. The atmosphere also retains heat during the night, thereby reducing the daily temperature extremes. |
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Terrestrial weather occurs almost exclusively in the [[troposphere|lower part of the atmosphere]], and serves as a convective system for redistributing heat.<ref>{{Cite book|url=https://books.google.com/?id=AJ4SnHbb-ZcC&pg=PA42|title=Environmental Science: Problems, Connections and Solutions| |
Terrestrial weather occurs almost exclusively in the [[troposphere|lower part of the atmosphere]], and serves as a convective system for redistributing heat.<ref>{{Cite book|url=https://books.google.com/books?id=AJ4SnHbb-ZcC&pg=PA42|title=Environmental Science: Problems, Connections and Solutions|last1=Miller|last2=Spoolman|first2=Scott|date=September 28, 2007|publisher=Cengage Learning|isbn=978-0-495-38337-6}}</ref> [[Ocean current]]s are another important factor in determining climate, particularly the major underwater [[thermohaline circulation]] which distributes heat energy from the equatorial oceans to the polar regions. These currents help to moderate the differences in temperature between winter and summer in the temperate zones. Also, without the redistributions of heat energy by the ocean currents and atmosphere, the tropics would be much hotter, and the [[polar region]]s much colder. |
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[[File:Lightnings sequence 2 animation-wcag.gif|thumb|left|[[Lightning]]]] |
[[File:Lightnings sequence 2 animation-wcag.gif|thumb|left|[[Lightning]]]] |
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Weather can have both beneficial and harmful effects. Extremes in weather, such as [[tornado]]es or [[hurricane]]s and [[cyclone]]s, can expend large amounts of energy along their paths, and produce devastation. Surface vegetation has evolved a dependence on the seasonal variation of the weather, and sudden changes lasting only a few years can have a dramatic effect, both on the vegetation and on the animals which depend on its growth for their food. |
Weather can have both beneficial and harmful effects. Extremes in weather, such as [[tornado]]es or [[hurricane]]s and [[cyclone]]s, can expend large amounts of energy along their paths, and produce devastation. Surface vegetation has evolved a dependence on the seasonal variation of the weather, and sudden changes lasting only a few years can have a dramatic effect, both on the vegetation and on the animals which depend on its growth for their food. |
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Climate is a measure of the long-term trends in the weather. Various factors are known to [[Climate |
Climate is a measure of the long-term trends in the weather. Various factors are known to [[Climate variability and change|influence the climate]], including ocean currents, surface [[albedo]], [[greenhouse gas]]es, variations in the solar luminosity, and changes to the Earth's orbit. Based on historical and geological records, the Earth is known to have undergone drastic [[climate change]]s in the past, including [[ice age]]s. |
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[[File: |
[[File:A tornado near Anadarko, Oklahoma, on May 3, 1999.jpg|thumb|A tornado in central [[Oklahoma]]]] |
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The climate of a region depends on a number of factors, especially [[latitude]]. A latitudinal band of the surface with similar climatic attributes forms a climate region. There are a number of such regions, ranging from the [[tropical climate]] at the equator to the [[polar climate]] in the northern and southern extremes. Weather is also influenced by the seasons, which result from the [[Earth]]'s [[axis of rotation|axis]] being [[axial tilt|tilted]] relative to its [[orbital plane (astronomy)|orbital plane]]. Thus, at any given time during the summer or winter, one part of the Earth is more directly exposed to the rays of the [[sun]]. This exposure alternates as the Earth revolves in its orbit. At any given time, regardless of season, the [[ |
The climate of a region depends on a number of factors, especially [[latitude]]. A latitudinal band of the surface with similar climatic attributes forms a climate region. There are a number of such regions, ranging from the [[tropical climate]] at the equator to the [[polar climate]] in the northern and southern extremes. Weather is also influenced by the seasons, which result from the [[Earth]]'s [[axis of rotation|axis]] being [[axial tilt|tilted]] relative to its [[orbital plane (astronomy)|orbital plane]]. Thus, at any given time during the summer or winter, one part of the Earth is more directly exposed to the rays of the [[sun]]. This exposure alternates as the Earth revolves in its orbit. At any given time, regardless of season, the [[Northern Hemisphere|Northern]] and [[Southern Hemisphere|Southern]] Hemispheres experience opposite seasons. |
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Weather is a [[Chaos theory|chaotic system]] that is readily modified by small changes to the [[Natural environment|environment]], so accurate [[Meteorology|weather forecasting]] is limited to only a few days.<ref>{{Cite journal| |
Weather is a [[Chaos theory|chaotic system]] that is readily modified by small changes to the [[Natural environment|environment]], so accurate [[Meteorology|weather forecasting]] is limited to only a few days.<ref>{{Cite journal|last1=Stern|first1=Harvey|last2=Davidson|first2=Noel|date=May 25, 2015|title=Trends in the skill of weather prediction at lead times of 1–14 days|journal=Quarterly Journal of the Royal Meteorological Society|volume=141|issue=692|pages=2726–2736|doi=10.1002/qj.2559|bibcode=2015QJRMS.141.2726S|s2cid=119942734|doi-access=free}}</ref> Overall, two things are happening worldwide: (1) temperature is increasing on the average; and (2) regional climates have been undergoing noticeable changes.<ref>{{cite web|title=Tropical Ocean Warming Drives Recent Northern Hemisphere Climate Change|website=Science Daily|date=April 6, 2001|url=https://www.sciencedaily.com/releases/2001/04/010406073554.htm|access-date=May 24, 2006|archive-url=https://web.archive.org/web/20060421222313/http://www.sciencedaily.com/releases/2001/04/010406073554.htm|archive-date=April 21, 2006|url-status=live|df=mdy-all}}</ref> |
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==Water on Earth== |
==Water on Earth== |
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[[File:44 - Iguazu - Décembre 2007.jpg|thumb|upright=1.4|The [[Iguazu Falls]] on the border between [[Brazil]] and [[Argentina]]]] |
[[File:44 - Iguazu - Décembre 2007.jpg|thumb|upright=1.4|The [[Iguazu Falls]] on the border between [[Brazil]] and [[Argentina]]]] |
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{{Main|Water}} |
{{Main|Water}} |
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Water is a [[chemical substance]] that is composed of [[hydrogen]] and [[oxygen]] (H2O) and is vital for all known forms of life.<ref>{{cite web |url=https://www.un.org/waterforlifedecade/background.html |title=Water for Life |publisher=Un.org |date=March 22, 2005 |access-date=May 14, 2011 |archive-url=https://web.archive.org/web/20110514200432/http://www.un.org/waterforlifedecade/background.html |archive-date=May 14, 2011 |url-status=live |df=mdy-all }}</ref> In typical usage, "water" refers only to its liquid [[States of matter|form]], but it also has a solid state, [[ice]], and a [[gas]]eous state, [[water vapor]], or [[steam]]. <!--About 1.460 [[Tonne#Multiples|petatonnes]] (Pt) (10<sup>21</sup> kilograms) of water-->Water covers 71% of the [[Earth]]'s surface.<ref>{{cite web|url=https://www.cia.gov/the-world-factbook/countries/world/|title=World|work=CIA – World Fact Book|access-date=December 20, 2008|df=mdy-all|archive-date=January 26, 2021|archive-url=https://web.archive.org/web/20210126032610/https://www.cia.gov/the-world-factbook/countries/world/|url-status=live}}</ref> On Earth, it is found mostly in oceans and other large bodies of water, with 1.6% of water below ground in [[aquifer]]s and 0.001% in the [[atmosphere|air]] as [[vapor]], clouds, and [[precipitation (meteorology)|precipitation]].<ref>[https://web.archive.org/web/20070320034158/http://www.agu.org/sci_soc/mockler.html Water Vapor in the Climate System], Special Report, American Geophysical Union, December 1995.</ref><ref>[https://web.archive.org/web/20080220070111/http://www.unep.org/dewa/assessments/ecosystems/water/vitalwater/ Vital Water]. [[UNEP]].</ref> Oceans hold 97% of surface water, [[glacier]]s, and polar [[ice cap]]s 2.4%, and other land surface water such as rivers, lakes, and ponds 0.6%. Additionally, a minute amount of the Earth's water is contained within biological bodies and manufactured products. |
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===Oceans=== |
===Oceans=== |
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[[File:Ocean from Leblon.jpg|thumb|left|A view of the Atlantic Ocean from [[Leblon]], Rio de Janeiro |
[[File:Ocean from Leblon.jpg|thumb|left|A view of the Atlantic Ocean from [[Leblon]], Rio de Janeiro]] |
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{{Main|Ocean}} |
{{Main|Ocean}} |
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An ocean is a major body of [[Seawater|saline water]], and a principal component of the hydrosphere. Approximately 71% of the Earth's surface (an area of some 361 million square kilometers) is covered by ocean, a [[World Ocean|continuous body of water]] that is customarily divided into several principal oceans and smaller seas. More than half of this area is over {{convert|3000|m|ft|abbr=off|sp=us}} deep. Average oceanic [[salinity]] is around 35 [[parts per thousand]] (ppt) (3.5%), and nearly all seawater has a salinity in the range of 30 to 38 ppt. Though generally recognized as several 'separate' oceans, these waters comprise one global, interconnected body of salt water often referred to as the [[World Ocean]] or global ocean.<ref>"[http://www.answers.com/Ocean#Encyclopedia Ocean] {{Webarchive|url=https://web.archive.org/web/20110126035624/http://www.answers.com/topic/ocean#Encyclopedia |date=January 26, 2011 }}". ''The Columbia Encyclopedia.'' 2002. New York: Columbia University Press</ref><ref name="UNAoO">"[http://www.oceansatlas.com/unatlas/about/physicalandchemicalproperties/background/seemore1.html Distribution of land and water on the planet] {{webarchive|url=https://web.archive.org/web/20080531103749/http://www.oceansatlas.com/unatlas/about/physicalandchemicalproperties/background/seemore1.html |date=May 31, 2008 }}". [http://www.oceansatlas.com/ UN Atlas of the Oceans] {{Webarchive|url=https://web.archive.org/web/20080915105349/http://www.oceansatlas.com/ |date=September 15, 2008 }}</ref> This concept of a global ocean as a continuous body of water with relatively free interchange among its parts is of fundamental importance to [[oceanography]].<ref>{{cite journal | last1 = Spilhaus | first1 = Athelstan F | year = 1942 | title = Maps of the whole world ocean |
An ocean is a major body of [[Seawater|saline water]], and a principal component of the hydrosphere. Approximately 71% of the Earth's surface (an area of some 361 million square kilometers) is covered by ocean, a [[World Ocean|continuous body of water]] that is customarily divided into several principal oceans and smaller seas. More than half of this area is over {{convert|3000|m|ft|abbr=off|sp=us}} deep. Average oceanic [[salinity]] is around 35 [[parts per thousand]] (ppt) (3.5%), and nearly all seawater has a salinity in the range of 30 to 38 ppt. Though generally recognized as several 'separate' oceans, these waters comprise one global, interconnected body of salt water often referred to as the [[World Ocean]] or global ocean.<ref>"[http://www.answers.com/Ocean#Encyclopedia Ocean] {{Webarchive|url=https://web.archive.org/web/20110126035624/http://www.answers.com/topic/ocean#Encyclopedia |date=January 26, 2011 }}". ''The Columbia Encyclopedia.'' 2002. New York: Columbia University Press</ref><ref name="UNAoO">"[http://www.oceansatlas.com/unatlas/about/physicalandchemicalproperties/background/seemore1.html Distribution of land and water on the planet] {{webarchive|url=https://web.archive.org/web/20080531103749/http://www.oceansatlas.com/unatlas/about/physicalandchemicalproperties/background/seemore1.html |date=May 31, 2008 }}". [http://www.oceansatlas.com/ UN Atlas of the Oceans] {{Webarchive|url=https://web.archive.org/web/20080915105349/http://www.oceansatlas.com/ |date=September 15, 2008 }}</ref> This concept of a global ocean as a continuous body of water with relatively free interchange among its parts is of fundamental importance to [[oceanography]].<ref>{{cite journal | last1 = Spilhaus | first1 = Athelstan F | year = 1942 | title = Maps of the whole world ocean | journal = Geographical Review | volume = 32 | issue = 3| pages = 431–435 | doi=10.2307/210385| jstor = 210385 | bibcode = 1942GeoRv..32..431S }}</ref> |
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The major oceanic divisions are defined in part by the [[continent]]s, various [[archipelago]]s, and other criteria: these divisions are (in descending order of size) the [[Pacific Ocean]], the [[Atlantic Ocean]], the [[Indian Ocean]], the [[Southern Ocean]], and the [[Arctic Ocean]]. Smaller regions of the oceans are called seas, |
The major oceanic divisions are defined in part by the [[continent]]s, various [[archipelago]]s, and other criteria: these divisions are (in descending order of size) the [[Pacific Ocean]], the [[Atlantic Ocean]], the [[Indian Ocean]], the [[Southern Ocean]], and the [[Arctic Ocean]]. Smaller regions of the oceans are called seas, gulfs, [[bay]]s and other names. There are also [[salt lake]]s, which are smaller bodies of landlocked saltwater that are not interconnected with the World Ocean. Two notable examples of salt lakes are the [[Aral Sea]] and the [[Great Salt Lake]]. |
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===Lakes=== |
===Lakes=== |
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A lake (from Latin word ''lacus'') is a [[terrain feature]] (or [[physical feature]]), a body of liquid on the surface of a world that is localized to the bottom of [[Depression (geology)|basin]] (another type of landform or terrain feature; that is, it is not global) and moves slowly if it moves at all. On Earth, a body of water is considered a lake when it is inland, not part of the ocean, is larger and deeper than a pond, and is fed by a river.<ref> |
A lake (from Latin word ''lacus'') is a [[terrain feature]] (or [[physical feature]]), a body of liquid on the surface of a world that is localized to the bottom of [[Depression (geology)|basin]] (another type of landform or terrain feature; that is, it is not global) and moves slowly if it moves at all. On Earth, a body of water is considered a lake when it is inland, not part of the ocean, is larger and deeper than a pond, and is fed by a river.<ref> |
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{{cite web |
{{cite web |
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|author=Britannica Online |
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|title=Lake (physical feature) |
|title=Lake (physical feature) |
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|quote=[a Lake is] any relatively large body of slowly moving or standing water that occupies an inland basin of appreciable size. Definitions that precisely distinguish lakes, ponds, swamps, and even rivers and other bodies of nonoceanic water are not well established. It may be said, however, that rivers and streams are relatively fast moving; marshes and swamps contain relatively large quantities of grasses, trees, or shrubs; and ponds are relatively small in comparison to lakes. Geologically defined, lakes are temporary bodies of water. |
|quote=[a Lake is] any relatively large body of slowly moving or standing water that occupies an inland basin of appreciable size. Definitions that precisely distinguish lakes, ponds, swamps, and even rivers and other bodies of nonoceanic water are not well established. It may be said, however, that rivers and streams are relatively fast moving; marshes and swamps contain relatively large quantities of grasses, trees, or shrubs; and ponds are relatively small in comparison to lakes. Geologically defined, lakes are temporary bodies of water. |
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|archive-url=https://web.archive.org/web/20080611194244/ |
|archive-url=https://web.archive.org/web/20080611194244/https://www.britannica.com/EBchecked/topic/328083/lake |
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|archive-date=June 11, 2008 |
|archive-date=June 11, 2008 |
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</ref><ref>{{cite web|title=Lake Definition|url=http://www.dictionary.com/browse/lake|website=Dictionary.com| |
</ref><ref>{{cite web|title=Lake Definition|url=http://www.dictionary.com/browse/lake|website=Dictionary.com|access-date=September 6, 2016|archive-url=https://web.archive.org/web/20160905184816/http://www.dictionary.com/browse/lake|archive-date=September 5, 2016|url-status=live|df=mdy-all}}</ref> The only world other than Earth known to harbor lakes is [[Titan (moon)|Titan]], Saturn's largest moon, which has lakes of [[ethane]], most likely mixed with [[methane]]. It is not known if Titan's lakes are fed by rivers, though Titan's surface is carved by numerous river beds. Natural lakes on Earth are generally found in mountainous areas, [[rift zone]]s, and areas with ongoing or recent [[glacier|glaciation]]. Other lakes are found in [[endorheic basin]]s or along the courses of mature rivers. In some parts of the world, there are many lakes because of chaotic drainage patterns left over from the [[Last Glacial Period|last ice age]]. All lakes are temporary over geologic time scales, as they will slowly fill in with sediments or spill out of the basin containing them. |
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====Ponds==== |
====Ponds==== |
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[[File:Mill Pond Sunset.jpg|thumb|The Westborough Reservoir (Mill Pond) in [[Westborough, Massachusetts]] |
[[File:Mill Pond Sunset.jpg|thumb|The Westborough Reservoir (Mill Pond) in [[Westborough, Massachusetts]]]] |
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{{Main|Pond}} |
{{Main|Pond}} |
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A '''pond''' is a [[body of water|body]] of [[Water stagnation|standing water]], either natural or |
A '''pond''' is a [[body of water|body]] of [[Water stagnation|standing water]], either natural or human-made, that is usually smaller than a lake. A wide variety of human-made bodies of water are classified as ponds, including [[water garden]]s designed for aesthetic ornamentation, [[fish pond]]s designed for commercial fish breeding, and [[solar pond]]s designed to store thermal energy. Ponds and lakes are distinguished from streams via [[current (stream)|current]] speed. While currents in streams are easily observed, ponds and lakes possess thermally driven micro-currents and moderate wind driven currents. These features distinguish a pond from many other aquatic terrain features, such as [[stream pool]]s and [[tide pool]]s. |
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===Rivers=== |
===Rivers=== |
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[[File:View from Cairo Tower 31march2007.jpg|thumb|left|The [[Nile]] river in [[Cairo]], |
[[File:View from Cairo Tower 31march2007.jpg|thumb|left|The [[Nile]] river in [[Cairo]], Egypt's capital city]] |
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{{Main|River}} |
{{Main|River}} |
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A river is a natural [[watercourse]],<ref>[http://www.merriam-webster.com/dictionary/river River {definition}] {{Webarchive|url=https://web.archive.org/web/20100221200545/http://www.merriam-webster.com/dictionary/river |date=February 21, 2010 }} from Merriam-Webster. Accessed February 2010.</ref> usually [[freshwater]], flowing towards an ocean, a lake, a sea or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including stream, creek, brook, rivulet, and rill; there is no general rule that defines what can be called a river. Many names for small rivers are specific to geographic location; one example is ''Burn'' in Scotland and North-east England. Sometimes a river is said to be larger than a creek, but this is not always the case, due to vagueness in the language.<ref>[http://geonames.usgs.gov/domestic/faqs.htm USGS – U.S. Geological Survey – FAQs] {{Webarchive|url=https://web.archive.org/web/20150701155523/http://geonames.usgs.gov/domestic/faqs.htm |date=July 1, 2015 }}, No. 17 What is the difference between mountain, hill, and [[Summit (topography)|peak]]; lake and pond; or river and [[stream|creek]]?</ref> A river is part of the [[hydrological cycle]]. Water within a river is generally collected from [[Precipitation (meteorology)|precipitation]] through [[surface runoff]], [[groundwater]] recharge, [[Spring (hydrology)|springs]], and the release of stored water in natural ice and snowpacks (i.e., from [[glacier]]s). |
A river is a natural [[watercourse]],<ref>[http://www.merriam-webster.com/dictionary/river River {definition}] {{Webarchive|url=https://web.archive.org/web/20100221200545/http://www.merriam-webster.com/dictionary/river |date=February 21, 2010 }} from Merriam-Webster. Accessed February 2010.</ref> usually [[freshwater]], flowing towards an ocean, a lake, a sea or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including stream, creek, brook, rivulet, and rill; there is no general rule that defines what can be called a river. Many names for small rivers are specific to geographic location; one example is ''Burn'' in Scotland and North-east England. Sometimes a river is said to be larger than a creek, but this is not always the case, due to vagueness in the language.<ref>[http://geonames.usgs.gov/domestic/faqs.htm USGS – U.S. Geological Survey – FAQs] {{Webarchive|url=https://web.archive.org/web/20150701155523/http://geonames.usgs.gov/domestic/faqs.htm |date=July 1, 2015 }}, No. 17 What is the difference between mountain, hill, and [[Summit (topography)|peak]]; lake and pond; or river and [[stream|creek]]?</ref> A river is part of the [[hydrological cycle]]. Water within a river is generally collected from [[Precipitation (meteorology)|precipitation]] through [[surface runoff]], [[groundwater]] recharge, [[Spring (hydrology)|springs]], and the release of stored water in natural ice and snowpacks (i.e., from [[glacier]]s). |
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==Ecosystems==<!-- This section is linked from Nature --> |
==Ecosystems==<!-- This section is linked from Nature --> |
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[[File:View of loch lomond.JPG|thumb|left|[[Loch Lomond]] in Scotland forms a relatively isolated ecosystem. The fish community of this lake has remained unchanged over a very long period of time.<ref>{{cite journal|last=Adams|first=C.E.|title=The fish community of Loch Lomond, Scotland: its history and rapidly changing status|journal=Hydrobiologia|date=1994|volume=290|issue=1–3|pages=91–102|url=http://cat.inist.fr/?aModele=afficheN&cpsidt=3302548|doi=10.1007/BF00008956| |
[[File:View of loch lomond.JPG|thumb|left|[[Loch Lomond]] in Scotland forms a relatively isolated ecosystem. The fish community of this lake has remained unchanged over a very long period of time.<ref>{{cite journal|last=Adams|first=C.E.|title=The fish community of Loch Lomond, Scotland: its history and rapidly changing status|journal=Hydrobiologia|date=1994|volume=290|issue=1–3|pages=91–102|url=http://cat.inist.fr/?aModele=afficheN&cpsidt=3302548|doi=10.1007/BF00008956|s2cid=6894397|access-date=January 5, 2007|archive-url=https://web.archive.org/web/20120114115347/http://cat.inist.fr/?aModele=afficheN&cpsidt=3302548|archive-date=January 14, 2012|url-status=live|df=mdy-all|doi-access=free|bibcode=1994HyBio.290...91A }}</ref>]] |
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[[File:Aravalli.jpg|thumb|left|Lush green [[Aravalli Range|Aravalli Mountain Range]] in the Desert country – [[Rajasthan]], India. |
[[File:Aravalli.jpg|thumb|left|Lush green [[Aravalli Range|Aravalli Mountain Range]] in the Desert country – [[Rajasthan]], India.]] |
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[[File:Chicago Downtown Aerial View.jpg|thumb|An aerial view of a [[human ecosystem]]. Pictured is the city of Chicago]] |
[[File:Chicago Downtown Aerial View.jpg|thumb|An aerial view of a [[human ecosystem]]. Pictured is the city of Chicago.]] |
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{{Main|Ecology|Ecosystem}} |
{{Main|Ecology|Ecosystem}} |
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Ecosystems are composed of a variety of [[biotic component|biotic]] and [[abiotic component]]s that function in an interrelated way.<ref>{{cite web |last=Pidwirny |first=Michael |date=2006 |work=Fundamentals of Physical Geography (2nd Edition) |title=Introduction to the Biosphere: Introduction to the Ecosystem Concept |url=http://www.physicalgeography.net/fundamentals/9j.html | |
Ecosystems are composed of a variety of [[biotic component|biotic]] and [[abiotic component]]s that function in an interrelated way.<ref>{{cite web |last=Pidwirny |first=Michael |date=2006 |work=Fundamentals of Physical Geography (2nd Edition) |title=Introduction to the Biosphere: Introduction to the Ecosystem Concept |url=http://www.physicalgeography.net/fundamentals/9j.html |access-date=September 28, 2006 |archive-url=https://web.archive.org/web/20110718040429/http://www.physicalgeography.net/fundamentals/9j.html |archive-date=July 18, 2011 |url-status=live |df=mdy-all }}</ref> The structure and composition is determined by various environmental factors that are interrelated. Variations of these factors will initiate dynamic modifications to the ecosystem. Some of the more important components are [[soil]], [[atmosphere]], radiation from the [[sun]], water, and living organisms. |
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[[File:PenasBlancas, part of the Bosawas Reserve, Jinotega Department, Nicaragua.jpg|thumb|left|Peñas Blancas, part of the [[Bosawás Biosphere Reserve]]. Located northeast of the city of [[Jinotega]] in Northeastern Nicaragua |
[[File:PenasBlancas, part of the Bosawas Reserve, Jinotega Department, Nicaragua.jpg|thumb|left|Peñas Blancas, part of the [[Bosawás Biosphere Reserve]]. Located northeast of the city of [[Jinotega]] in Northeastern Nicaragua]] |
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Central to the ecosystem concept is the idea that [[living organism]]s interact with every other element in their local [[environment (biophysical)|environment]]. Eugene Odum, a founder of ecology, stated: "Any unit that includes all of the organisms (ie: the "community") in a given area interacting with the physical environment so that a flow of energy leads to clearly defined trophic structure, biotic diversity, and material cycles (i.e.: exchange of materials between living and nonliving parts) within the system is an ecosystem."<ref name="Odum1971">Odum, EP (1971) ''Fundamentals of ecology'', 3rd edition, Saunders New York</ref> Within the ecosystem, species are connected and dependent upon one another in the [[food chain]], and exchange energy and [[matter]] between themselves as well as with their environment.<ref>{{cite web |last=Pidwirny |first=Michael |date=2006 |work=Fundamentals of Physical Geography (2nd edition) |title=Introduction to the Biosphere: Organization of Life |url=http://www.physicalgeography.net/fundamentals/9d.html | |
Central to the ecosystem concept is the idea that [[living organism]]s interact with every other element in their local [[environment (biophysical)|environment]]. Eugene Odum, a founder of ecology, stated: "Any unit that includes all of the organisms (ie: the "community") in a given area interacting with the physical environment so that a flow of energy leads to clearly defined trophic structure, biotic diversity, and material cycles (i.e.: exchange of materials between living and nonliving parts) within the system is an ecosystem."<ref name="Odum1971">Odum, EP (1971) ''Fundamentals of ecology'', 3rd edition, Saunders New York</ref> Within the ecosystem, species are connected and dependent upon one another in the [[food chain]], and exchange energy and [[matter]] between themselves as well as with their environment.<ref>{{cite web |last=Pidwirny |first=Michael |date=2006 |work=Fundamentals of Physical Geography (2nd edition) |title=Introduction to the Biosphere: Organization of Life |url=http://www.physicalgeography.net/fundamentals/9d.html |access-date=September 28, 2006 |archive-url=https://web.archive.org/web/20110813100946/http://www.physicalgeography.net/fundamentals/9d.html |archive-date=August 13, 2011 |url-status=live |df=mdy-all }}</ref> The human ecosystem concept is based on the human/nature [[dichotomy]] and the idea that all species are ecologically dependent on each other, as well as with the abiotic constituents of their [[biotope]].<ref>{{Cite book|url=https://books.google.com/books?id=-s5oRDUuMSIC&pg=PA237|title=Biotechnology Fundamentals|last=Khan|first=Firdos Alam|date=2011|publisher=CRC Press|isbn=978-1-4398-2009-4}}</ref> |
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A smaller unit of size is called a [[microecosystem]]. For example, a microsystem can be a stone and all the life under it. A ''macroecosystem'' might involve a whole [[ecoregion]], with its [[drainage basin]].<ref>{{cite journal|last=Bailey |first=Robert G. |date=April 2004 |title=Identifying Ecoregion Boundaries |journal=Environmental Management |volume=34 |pmid=15883869 |issue=Supplement 1 |url=http://www.fs.fed.us/institute/news_info/Identifying_ecoregion_boundaries.pdf |doi=10.1007/s00267-003-0163-6 |pages= |
A smaller unit of size is called a [[microecosystem]]. For example, a microsystem can be a stone and all the life under it. A ''macroecosystem'' might involve a whole [[ecoregion]], with its [[drainage basin]].<ref>{{cite journal|last=Bailey |first=Robert G. |date=April 2004 |title=Identifying Ecoregion Boundaries |journal=Environmental Management |volume=34 |pmid=15883869 |issue=Supplement 1 |url=http://www.fs.fed.us/institute/news_info/Identifying_ecoregion_boundaries.pdf |doi=10.1007/s00267-003-0163-6 |pages=S14–S26 |bibcode=2004EnMan..34S..14B |s2cid=31998098 |url-status=dead |archive-url=https://web.archive.org/web/20091001013622/http://www.fs.fed.us/institute/news_info/Identifying_ecoregion_boundaries.pdf |archive-date=October 1, 2009 }}</ref> |
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===Wilderness=== |
===Wilderness=== |
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[[File:Biogradska suma.jpg|thumb|[[Old-growth forest|Old growth]] [[European Beech]] forest in [[Biogradska Gora]] National Park, [[Montenegro]] |
[[File:Biogradska suma.jpg|thumb|[[Old-growth forest|Old growth]] [[European Beech]] forest in [[Biogradska Gora]] National Park, [[Montenegro]]]] |
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{{Main|Wilderness}} |
{{Main|Wilderness}} |
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'''Wilderness''' is generally defined as areas that have not been significantly modified by human activity. Wilderness areas can be found in preserves, estates, farms, conservation preserves, ranches, [[:Category:national forests|national forests]], [[national park]]s, and even in urban areas along rivers, gulches, or otherwise undeveloped areas. Wilderness areas and protected [[parks]] are considered important for the survival of certain [[species]], ecological studies, [[Habitat conservation|conservation]], and solitude. Some nature writers believe wilderness areas are vital for the human spirit and creativity,<ref name="Man p155-157">Botkin, Daniel B. (2000) ''No Man's Garden'', Island Press, pp. |
'''Wilderness''' is generally defined as areas that have not been significantly modified by human activity. Wilderness areas can be found in preserves, estates, farms, conservation preserves, ranches, [[:Category:national forests|national forests]], [[national park]]s, and even in urban areas along rivers, gulches, or otherwise undeveloped areas. Wilderness areas and protected [[parks]] are considered important for the survival of certain [[species]], ecological studies, [[Habitat conservation|conservation]], and solitude. Some nature writers believe wilderness areas are vital for the human spirit and creativity,<ref name="Man p155-157">Botkin, Daniel B. (2000) ''No Man's Garden'', Island Press, pp. 155–157, {{ISBN|1-55963-465-0}}.</ref> and some ecologists consider wilderness areas to be an integral part of the Earth's self-sustaining natural [[ecosystem]] (the [[biosphere]]). They may also preserve historic [[genetics|genetic]] traits and that they provide [[habitat]] for wild [[flora (plants)|flora]] and [[fauna (animals)|fauna]] that may be difficult or impossible to recreate in [[zoo]]s, [[arboretum]]s, or [[laboratory|laboratories]]. |
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==Life== |
==Life== |
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{{Life timeline}} |
{{Life timeline}} |
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[[File:Malards in Golden Gate Park.jpg|thumb|left|upright|Female mallard and ducklings – [[reproduction]] is essential for continuing life]] |
[[File:Malards in Golden Gate Park.jpg|thumb|left|upright|Female mallard and ducklings – [[reproduction]] is essential for continuing life.]] |
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{{Main|Life|Biology|Biosphere}} |
{{Main|Life|Biology|Biosphere}} |
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Although there is no universal agreement on the definition of life, scientists generally accept that the biological manifestation of life is characterized by [[Organism|organization]], [[metabolism]], [[cell growth|growth]], [[adaptation]], response to [[stimulus (physiology)|stimuli]], and [[reproduction]].<ref>{{cite web|date=2006 |url=http://www.calacademy.org/exhibits/xtremelife/what_is_life.php |title=Definition of Life |publisher=California Academy of Sciences | |
Although there is no universal agreement on the definition of life, scientists generally accept that the biological manifestation of life is characterized by [[Organism|organization]], [[metabolism]], [[cell growth|growth]], [[adaptation]], response to [[stimulus (physiology)|stimuli]], and [[reproduction]].<ref>{{cite web |date=2006 |url=http://www.calacademy.org/exhibits/xtremelife/what_is_life.php |title=Definition of Life |publisher=California Academy of Sciences |access-date=January 7, 2007 |url-status=dead |archive-url=https://web.archive.org/web/20070208220940/http://www.calacademy.org/exhibits/xtremelife/what_is_life.php |archive-date=February 8, 2007 }}</ref> Life may also be said to be simply the characteristic state of [[organism]]s. |
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Present day organisms from [[virus]]es to humans possess a self-replicating informational molecule (genome), either [[DNA]] or [[RNA]] (as in some viruses), and such an informational molecule is probably intrinsic to life. It is likely that the earliest forms of life were based on a self-replicating informational molecule ([[genome]]), perhaps RNA<ref>{{cite journal |vauthors=Neveu M, Kim HJ, Benner SA |title=The "strong" RNA world hypothesis: fifty years old |journal=Astrobiology |volume=13 |issue=4 |pages=391–403 |date=April 2013 |pmid=23551238 |doi=10.1089/ast.2012.0868 |bibcode=2013AsBio..13..391N |url=}}</ref><ref>{{cite journal |vauthors=Cech TR |title=The RNA worlds in context |journal=Cold Spring Harb Perspect Biol |volume=4 |issue=7 |pages=a006742 |date=July 2012 |pmid=21441585 |pmc=3385955 |doi=10.1101/cshperspect.a006742 |url=}}</ref> or a molecule more primitive than RNA or DNA. The specific [[deoxyribonucleotide]]/[[ribonucleotide]] sequence in each currently extant individual organism contains sequence information that functions to promotes survival, [[reproduction]], and the capacity to acquire resources necessary for reproduction, and such sequences probably emerged early in the evolution of life. Survival functions present early in the evolution of life likely also included genomic sequences that promote the avoidance of damage to the self-replicating molecule and also the capability to [[DNA repair|repair such damages]] that do occur. Repair of some genome damages may have involved using information from another similar molecule by a process of [[genetic recombination|recombination]] (a primitive form of [[sexual reproduction|sexual interaction]]).<ref>{{cite journal |vauthors=Bernstein H, Byerly HC, Hopf FA, Michod RE |title=Genetic damage, mutation, and the evolution of sex |journal=Science |volume=229 |issue=4719 |pages=1277–81 |date=September 1985 |pmid=3898363 |doi=10.1126/science.3898363 |bibcode=1985Sci...229.1277B |url=}}</ref> |
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Properties common to terrestrial organisms (plants, animals, [[Fungus|fungi]], [[protist]]s, [[archaea]], and bacteria) are that they are cellular, carbon-and-water-based with complex organization, having a metabolism, a capacity to grow, respond to stimuli, and reproduce. An entity with these properties is generally considered life. However, not every definition of life considers all of these properties to be essential. Human-made [[Artificial life|analogs of life]] may also be considered to be life. |
Properties common to terrestrial organisms (plants, animals, [[Fungus|fungi]], [[protist]]s, [[archaea]], and bacteria) are that they are cellular, carbon-and-water-based with complex organization, having a metabolism, a capacity to grow, respond to stimuli, and reproduce. An entity with these properties is generally considered life. However, not every definition of life considers all of these properties to be essential. Human-made [[Artificial life|analogs of life]] may also be considered to be life. |
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The [[biosphere]] is the part of Earth's outer shell—including land, surface rocks, water, air and the atmosphere—within which life occurs, and which [[Biology|biotic]] processes in turn alter or transform. From the broadest [[Geophysiology|geophysiological]] point of view, the biosphere is the global ecological system integrating all living beings and their relationships, including their interaction with the elements of the [[lithosphere]] (rocks), [[hydrosphere]] (water), and [[atmosphere]] (air). The entire Earth contains over 75 billion tons (150 ''trillion'' pounds or about 6.8×10<sup>13</sup> kilograms) of [[biomass (ecology)|biomass]] (life), which lives within various environments within the biosphere.<ref>The figure "about one-half of one percent" takes into account the following (See, e.g., {{cite book |last=Leckie |first=Stephen |date=1999 |chapter=How Meat-centred Eating Patterns Affect Food Security and the Environment | |
The [[biosphere]] is the part of Earth's outer shell—including land, surface rocks, water, air and the atmosphere—within which life occurs, and which [[Biology|biotic]] processes in turn alter or transform. From the broadest [[Geophysiology|geophysiological]] point of view, the biosphere is the global ecological system integrating all living beings and their relationships, including their interaction with the elements of the [[lithosphere]] (rocks), [[hydrosphere]] (water), and [[atmosphere]] (air). The entire Earth contains over 75 billion tons (150 ''trillion'' pounds or about 6.8×10<sup>13</sup> kilograms) of [[biomass (ecology)|biomass]] (life), which lives within various environments within the biosphere.<ref>The figure "about one-half of one percent" takes into account the following (See, e.g., {{cite book |last=Leckie |first=Stephen |date=1999 |chapter=How Meat-centred Eating Patterns Affect Food Security and the Environment |chapter-url=http://www.idrc.ca/en/ev-30610-201-1-DO_TOPIC.html |title=For hunger-proof cities: sustainable urban food systems |publisher=International Development Research Centre |location=Ottawa |isbn=978-0-88936-882-8 |archive-url=https://web.archive.org/web/20101113020336/http://www.idrc.ca/en/ev-30610-201-1-DO_TOPIC.html |archive-date=November 13, 2010 }}, which takes global average weight as 60 kg.), the total human biomass is the average weight multiplied by the current human population of approximately 6.5 billion (see, ''e.g.'', {{cite web |title=World Population Information |url=https://www.census.gov/ipc/www/world.html |access-date=September 28, 2006 |publisher=U.S. Census Bureau }}{{Dead link|date=February 2019 |bot=InternetArchiveBot |fix-attempted=yes }}): Assuming 60–70 kg to be the average human mass (approximately 130–150 [[pound (mass)|lb]] on the average), an approximation of total global human mass of between 390 billion (390×10<sup>9</sup>) and 455 billion kg (between 845 billion and 975 billion lb, or about 423 million–488 million [[short ton]]s). The total biomass of all kinds on earth is estimated to be in excess of 6.8 x 10<sup>13</sup> kg (75 billion short tons). By these calculations, the portion of total biomass accounted for by humans would be very roughly 0.6%.</ref> |
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Over nine-tenths of the total biomass on Earth is plant life, on which animal life depends very heavily for its existence.<ref>{{cite web |first=Peter V. |last=Sengbusch |title=The Flow of Energy in Ecosystems – Productivity, Food Chain, and Trophic Level |work=Botany online |publisher=University of Hamburg Department of Biology |url=http://www.biologie.uni-hamburg.de/b-online/e54/54c.htm | |
Over nine-tenths of the total biomass on Earth is plant life, on which animal life depends very heavily for its existence.<ref>{{cite web |first=Peter V. |last=Sengbusch |title=The Flow of Energy in Ecosystems – Productivity, Food Chain, and Trophic Level |work=Botany online |publisher=University of Hamburg Department of Biology |url=http://www.biologie.uni-hamburg.de/b-online/e54/54c.htm |access-date=September 23, 2006 |archive-url=https://web.archive.org/web/20110726071651/http://www.biologie.uni-hamburg.de/b-online/e54/54c.htm |archive-date=July 26, 2011 |url-status=dead |df=mdy-all }}</ref> More than 2 million species of plant and animal life have been identified to date,<ref>{{cite web |last=Pidwirny |first=Michael |date=2006 |work=Fundamentals of Physical Geography (2nd Edition) |title=Introduction to the Biosphere: Species Diversity and Biodiversity |url=http://www.physicalgeography.net/fundamentals/9h.html |access-date=September 23, 2006 |archive-url=https://web.archive.org/web/20110718040705/http://www.physicalgeography.net/fundamentals/9h.html |archive-date=July 18, 2011 |url-status=live |df=mdy-all }}</ref> and estimates of the actual number of existing species range from several million to well over 50 million.<ref>{{cite web |url=http://faculty.plattsburgh.edu/thomas.wolosz/howmanysp.htm |title=How Many Species are There? |work=Extinction Web Page Class Notes |access-date=September 23, 2006 |url-status=dead |archive-url=https://web.archive.org/web/20060909194319/http://faculty.plattsburgh.edu/thomas.wolosz/howmanysp.htm |archive-date=September 9, 2006 }}</ref><ref>"Animal." World Book Encyclopedia. 16 vols. Chicago: World Book, 2003. This source gives an estimate of from 2 to 50 million.</ref><ref>{{cite web |url=https://www.sciencedaily.com/releases/2003/05/030526103731.htm |title=Just How Many Species Are There, Anyway? |website=Science Daily |date=May 2003 |access-date=September 26, 2006 |archive-url=https://web.archive.org/web/20070211001529/http://www.sciencedaily.com/releases/2003/05/030526103731.htm |archive-date=February 11, 2007 |url-status=live |df=mdy-all }}</ref> The number of individual species of life is constantly in some degree of flux, with new species appearing and others ceasing to exist on a continual basis.<ref>{{cite web |last=Withers |first=Mark A. |display-authors=etal |title=Changing Patterns in the Number of Species in North American Floras |work=Land Use History of North America |url=http://biology.usgs.gov/luhna/chap4.html |date=1998 |access-date=September 26, 2006 |url-status=dead |archive-url=https://web.archive.org/web/20060923054200/http://biology.usgs.gov/luhna/chap4.html |archive-date=September 23, 2006 }} Website based on the contents of the book: {{cite book |editor=Sisk, T.D. |date=1998 |title=Perspectives on the land use history of North America: a context for understanding our changing environment |publisher=U.S. Geological Survey, Biological Resources Division |id=USGS/BRD/BSR-1998-0003 |edition=Revised September 1999}}</ref><ref>{{cite web |title=Tropical Scientists Find Fewer Species Than Expected |url=https://www.sciencedaily.com/releases/2002/04/020425072847.htm |date=April 2002 |website=Science Daily |access-date=September 27, 2006 |archive-url=https://web.archive.org/web/20060830182612/http://www.sciencedaily.com/releases/2002/04/020425072847.htm |archive-date=August 30, 2006 |url-status=live |df=mdy-all }}</ref> The total number of species is in rapid decline.<ref>{{cite journal |last=Bunker |first=Daniel E. |display-authors=etal |title=Species Loss and Aboveground Carbon Storage in a Tropical Forest |journal=Science |date=November 2005 |volume=310 |issue=5750 |pages=1029–1031 |doi=10.1126/science.1117682 |pmid=16239439 |bibcode = 2005Sci...310.1029B|citeseerx=10.1.1.465.7559 |s2cid=42696030 }}</ref><ref>{{cite journal |last=Wilcox |first=Bruce A. |title=Amphibian Decline: More Support for Biocomplexity as a Research Paradigm |journal=EcoHealth |date=2006 |volume=3 |issue=1 |doi=10.1007/s10393-005-0013-5|pages = 1–2|s2cid=23011961 }}</ref><ref>{{cite book |editor=Clarke, Robin |editor2=Robert Lamb |editor3=Dilys Roe Ward |date=2002 |title=Global environment outlook 3: past, present and future perspectives |chapter=Decline and loss of species |chapter-url=http://www.unep.org/geo/assessments/global-assessments/global-environment-outlook-3 |publisher=Nairobi, Kenya: UNEP |location=London; Sterling, VA |isbn=978-92-807-2087-7 |url-access=registration |url=https://archive.org/details/globalenvironmen0000unse_z8s0 }}</ref> |
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===Evolution=== |
===Evolution=== |
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[[File:Amazon Manaus forest.jpg|thumb|An area of the [[Amazon Rainforest]] shared between [[Colombia]] and [[Brazil]]. The [[tropical rainforest]]s of South America contain the largest [[biodiversity|diversity]] of species on [[Earth]].<ref>{{cite web|url=http://earthobservatory.nasa.gov/Newsroom/view.php?id=28907 |title=Why the Amazon Rainforest is So Rich in Species: News |publisher=Earthobservatory.nasa.gov |date=December 5, 2005 | |
[[File:Amazon Manaus forest.jpg|thumb|An area of the [[Amazon Rainforest]] shared between [[Colombia]] and [[Brazil]]. The [[tropical rainforest]]s of South America contain the largest [[biodiversity|diversity]] of species on [[Earth]].<ref>{{cite web|url=http://earthobservatory.nasa.gov/Newsroom/view.php?id=28907 |title=Why the Amazon Rainforest is So Rich in Species: News |publisher=Earthobservatory.nasa.gov |date=December 5, 2005 |access-date=May 14, 2011 |url-status=dead |archive-url=https://web.archive.org/web/20110225204348/http://earthobservatory.nasa.gov/Newsroom/view.php?id=28907 |archive-date=February 25, 2011 }}</ref><ref>{{cite web|url=http://earthobservatory.nasa.gov/Newsroom/view.php?id=28907 |title=Why The Amazon Rainforest Is So Rich in Species |publisher=Sciencedaily.com |date=December 5, 2005 |access-date=May 14, 2011 |url-status=dead |archive-url=https://web.archive.org/web/20110225204348/http://earthobservatory.nasa.gov/Newsroom/view.php?id=28907 |archive-date=February 25, 2011 }}</ref>]] |
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{{Main|Evolution}} |
{{Main|Evolution}} |
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The [[origin of life]] on Earth is not well understood, but it is known to have occurred at least 3.5 billion years ago,<ref name="Origin1">Schopf |
The [[origin of life]] on Earth is not well understood, but it is known to have occurred at least 3.5 billion years ago,<ref name="Origin1">{{cite journal|last1=Schopf|first1=J. William|last2=Kudryavtsev|first2=Anatoliy B.|last3=Czaja|first3=Andrew D.|last4=Tripathi|first4=Abhishek B.|title=Evidence of Archean life: Stromatolites and microfossils|journal=Precambrian Research|volume=158|issue=3–4|year=2007|pages=141–155|doi=10.1016/j.precamres.2007.04.009|bibcode=2007PreR..158..141S}}</ref><ref name="Origin2">{{cite journal | last1 = Schopf | first1 = JW | year = 2006 | title = Fossil evidence of Archaean life | doi = 10.1098/rstb.2006.1834 | journal = Philos Trans R Soc Lond B Biol Sci | volume = 361 | issue = 1470| pages = 869–885 | pmid=16754604 | pmc=1578735}}</ref><ref name="RavenJohnson2002">{{cite book|author1=Raven, Peter Hamilton |author2=Johnson, George Brooks |title=Biology|url=https://archive.org/details/biologyrave00rave|url-access=registration|access-date=July 7, 2013|date=2002|publisher=McGraw-Hill Education|isbn=978-0-07-112261-0|page=[https://archive.org/details/biologyrave00rave/page/68 68]|df=mdy-all}}</ref> during the [[hadean]] or [[archean]] eons on a [[Early Earth|primordial Earth]] that had a substantially different environment than is found at present.<ref name=Line>{{cite journal|author = Line, M.|title = The enigma of the origin of life and its timing|journal = Microbiology|volume = 148|issue = Pt 1|pages = 21–27|date=January 1, 2002| pmid = 11782495 | doi = 10.1099/00221287-148-1-21 |doi-access = free}}</ref> These life forms possessed the basic traits of self-replication and inheritable traits. Once life had appeared, the process of [[evolution]] by [[natural selection]] resulted in the development of ever-more diverse life forms. |
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Species that were unable to adapt to the changing environment and competition from other life forms became extinct. However, the [[fossil]] record retains evidence of many of these older species. Current fossil and [[DNA]] evidence shows that all existing species can trace a continual ancestry back to the first primitive life forms.<ref name=Line/> |
Species that were unable to adapt to the changing environment and competition from other life forms became extinct. However, the [[fossil]] record retains evidence of many of these older species. Current fossil and [[DNA]] evidence shows that all existing species can trace a continual ancestry back to the first primitive life forms.<ref name=Line/> |
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When basic forms of plant life developed the process of [[photosynthesis]] the sun's energy could be harvested to create conditions which allowed for more complex life forms.<ref>{{Cite web|url=https://phys.org/news/2016-03-photosynthesis-ancient-thought.html|title=Photosynthesis more ancient than thought, and most living things could do it|website= |
When basic forms of plant life developed the process of [[photosynthesis]] the sun's energy could be harvested to create conditions which allowed for more complex life forms.<ref>{{Cite web|url=https://phys.org/news/2016-03-photosynthesis-ancient-thought.html|title=Photosynthesis more ancient than thought, and most living things could do it|website=Phys.org|access-date=2019-01-19|archive-url=https://web.archive.org/web/20190120043127/https://phys.org/news/2016-03-photosynthesis-ancient-thought.html|archive-date=January 20, 2019|url-status=live|df=mdy-all}}</ref> The resultant [[oxygen]] accumulated in the atmosphere and gave rise to the [[ozone layer]]. The incorporation of smaller cells within larger ones resulted in the [[endosymbiotic theory|development of yet more complex cells]] called [[eukaryotes]].<ref>{{cite journal |first=L. V. |last=Berkner |author2=L. C. Marshall |date=May 1965 |title=On the Origin and Rise of Oxygen Concentration in the Earth's Atmosphere |journal=Journal of the Atmospheric Sciences |volume=22 |issue=3 |pages=225–261|doi=10.1175/1520-0469(1965)022<0225:OTOARO>2.0.CO;2 |bibcode=1965JAtS...22..225B |doi-access=free }}</ref> Cells within colonies became increasingly specialized, resulting in true multicellular organisms. With the ozone layer absorbing harmful [[ultraviolet radiation]], life colonized the surface of Earth. |
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===Microbes=== |
===Microbes=== |
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[[File:Yellow mite (Tydeidae) Lorryia formosa 2 edit.jpg|thumb|upright|A microscopic mite |
[[File:Yellow mite (Tydeidae) Lorryia formosa 2 edit.jpg|thumb|upright|A microscopic mite [[Mite|''Lorryia formosa'']]]] |
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{{Main|Microbe}} |
{{Main|Microbe}} |
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The first form of life to develop on the Earth were |
The first form of life to develop on the Earth were [[unicellular]], and they remained the only form of life until about a billion years ago when multi-cellular organisms began to appear.<ref>{{cite journal | |
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author = Schopf J|title = Disparate rates, differing fates: tempo and mode of evolution changed from the Precambrian to the Phanerozoic|journal = Proc Natl Acad Sci USA|volume = 91|issue = 15|pages = 6735–42|date = 1994|pmid = 8041691|doi = 10.1073/pnas.91.15.6735 | |
author = Schopf J|title = Disparate rates, differing fates: tempo and mode of evolution changed from the Precambrian to the Phanerozoic|journal = Proc Natl Acad Sci USA|volume = 91|issue = 15|pages = 6735–42|date = 1994|pmid = 8041691|doi = 10.1073/pnas.91.15.6735 | |
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pmc = 44277 |
pmc = 44277 |
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|bibcode = 1994PNAS...91.6735S}}</ref> Microorganisms |
|bibcode = 1994PNAS...91.6735S|doi-access = free}}</ref> Microorganisms or microbes are [[microscopic]], and smaller than the human eye can see.<ref>{{Britannica URL |dictionary/microorganism|Microorganism}}</ref> [[Microorganism]]s can be [[single-celled]], such as [[Bacteria]], [[Archaea]], many [[Protist]]a, and a minority of [[Fungus|Fungi]].<ref>{{cite web|url=https://www.biologyonline.com/dictionary/unicellular|title=Unicellular|work= BiologyOnline.com | access-date=5 August 2008}}</ref> |
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These life forms are found in almost every location on the Earth where there is liquid water, including in the Earth's interior.<ref>{{cite journal|author = Szewzyk U|author2 = Szewzyk R|author3 = Stenström T|title = Thermophilic, anaerobic bacteria isolated from a deep borehole in granite in Sweden|doi= 10.1073/pnas.91.5.1810|journal = Proc Natl Acad Sci USA|volume = 91|issue = 5|pages = |
These life forms are found in almost every location on the Earth where there is liquid water, including in the Earth's interior.<ref>{{cite journal|author = Szewzyk U|author2 = Szewzyk R|author3 = Stenström T|title = Thermophilic, anaerobic bacteria isolated from a deep borehole in granite in Sweden|doi= 10.1073/pnas.91.5.1810|journal = Proc Natl Acad Sci USA|volume = 91|issue = 5|pages = 1810–1813|date = 1994|pmid = 11607462|pmc = 43253|bibcode = 1994PNAS...91.1810S|doi-access = free}}</ref> |
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Their reproduction is both rapid and profuse. The combination of a high mutation rate and a [[horizontal gene transfer]]<ref>{{cite journal|author = Wolska K|title = Horizontal DNA transfer between bacteria in the environment|journal = Acta Microbiol Pol|volume = 52|issue = 3|pages = |
Their reproduction is both rapid and profuse. The combination of a high mutation rate and a [[horizontal gene transfer]]<ref>{{cite journal|author = Wolska K|title = Horizontal DNA transfer between bacteria in the environment|journal = Acta Microbiol Pol|volume = 52|issue = 3|pages = 233–243|date = 2003|pmid = 14743976}}</ref> ability makes them highly adaptable, and able to survive in new and sometimes very harsh environments, including [[outer space]].<ref>{{cite journal|author = Horneck G|title = Survival of microorganisms in space: a review|journal = Adv Space Res|volume = 1|issue = 14|pages = 39–48|date = 1981|pmid = 11541716|doi = 10.1016/0273-1177(81)90241-6}}</ref> They form an essential part of the planetary ecosystem. However, some microorganisms are [[pathogen]]ic and can post health risk to other organisms. |
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[[Virus|Viruses]] are [[pathogen|infectious agents]], but they are not autonomous [[Outline of life forms|life forms]], as it is the case for [[viroid|viroids]], [[satellite (biology)|satellites]], [[Defective interfering particle|DPIs]] and [[prion|prions]].<ref name="Solomon">{{cite book|last1=Solomon|first1=Eldra|last2=Martin |first2=Charles |last3=Martin |first3=Diana W. |last4=Berg |first4=Linda R. |title=Biology |date=2019|publisher=[[Cengage Learning]]|isbn=978-1305179899|pages=408, 420–422}}</ref> |
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===Plants and animals=== |
===Plants and animals=== |
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{{Main|Plant|Animal}} |
{{Main|Plant|Animal}} |
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[[File:Diversity of plants |
[[File:Diversity of plants (Streptophyta) version 2.png|thumb|left|A selection of diverse [[plant species]]]] |
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[[File:Animal diversity.png|thumb|A selection of diverse [[animal species]]]] |
[[File:Animal diversity.png|thumb|A selection of diverse [[animal species]]]] |
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Originally [[Aristotle]] divided all living things between plants, which generally do not move fast enough for humans to notice, and animals. In [[Carl Linnaeus|Linnaeus]]' system, these became the [[kingdom (biology)|kingdoms]] [[Vegetabilia]] (later [[ |
Originally [[Aristotle]] divided all living things between plants, which generally do not move fast enough for humans to notice, and animals. In [[Carl Linnaeus|Linnaeus]]' system, these became the [[kingdom (biology)|kingdoms]] [[Vegetabilia]] (later [[Plant]]ae) and [[Animal]]ia. Since then, it has become clear that the Plantae as originally defined included several unrelated groups, and the [[fungus|fungi]] and several groups of [[alga]]e were removed to new kingdoms. However, these are still often considered plants in many contexts. Bacterial life is sometimes included in flora,<ref>{{cite web |title=flora |url=http://webster.com/cgi-bin/dictionary?va=flora |work=Merriam-Webster Online Dictionary |publisher=Merriam-Webster |access-date=September 27, 2006 |archive-url=https://web.archive.org/web/20060430072626/http://webster.com/cgi-bin/dictionary?va=flora |archive-date=April 30, 2006 |url-status=dead |df=mdy-all }}</ref><ref>{{cite book |date=1998 |title=Status and Trends of the Nation's Biological Resources |chapter=Glossary |chapter-url=http://biology.usgs.gov/s+t/SNT/noframe/zy198.htm |publisher=Department of the Interior, Geological Survey |location=Reston, VA |id=SuDocs No. I 19.202:ST 1/V.1-2 |url-status=dead |archive-url=https://web.archive.org/web/20070715060359/http://biology.usgs.gov/s+t/SNT/noframe/zy198.htm |archive-date=July 15, 2007 }}</ref> and some classifications use the term ''bacterial flora'' separately from ''plant flora''. |
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Among the many ways of classifying plants are by regional [[flora]]s, which, depending on the purpose of study, can also include ''fossil flora'', remnants |
Among the many ways of classifying plants are by regional [[flora]]s, which, depending on the purpose of study, can also include ''fossil flora'', remnants of plant life from a previous era. People in many regions and countries take great pride in their individual arrays of characteristic flora, which can vary widely across the globe due to differences in climate and [[terrain]]. |
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Regional floras commonly are divided into categories such as ''native flora'' |
Regional floras commonly are divided into categories such as ''native flora'' or ''agricultural and garden flora''. Some types of "native flora" actually have been introduced centuries ago by people migrating from one region or continent to another, and become an integral part of the native, or natural flora of the place to which they were introduced. This is an example of how human interaction with nature can blur the boundary of what is considered nature. |
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Another category of plant has historically been carved out for ''weeds''. Though the term has fallen into disfavor among [[ |
Another category of plant has historically been carved out for ''weeds''. Though the term has fallen into disfavor among [[Botany|botanists]] as a formal way to categorize "useless" plants, the informal use of the word "weeds" to describe those plants that are deemed worthy of elimination is illustrative of the general tendency of people and societies to seek to alter or shape the course of nature. Similarly, animals are often categorized in ways such as ''domestic'', ''farm animals'', ''wild animals'', ''pests'', etc. according to their relationship to human life. |
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Animals as a category have several characteristics that generally set them apart from other living things. Animals are [[eukaryote|eukaryotic]] and usually [[multicellular]] |
Animals as a category have several characteristics that generally set them apart from other living things. Animals are [[eukaryote|eukaryotic]] and usually [[multicellular]], which separates them from bacteria, [[archaea]], and most [[protist]]s. They are [[heterotroph]]ic, generally digesting food in an internal chamber, which separates them from plants and [[alga]]e. They are also distinguished from plants, algae, and [[fungus|fungi]] by lacking [[cell wall]]s. |
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With a few exceptions—most notably the two [[Phylum|phyla]] consisting of [[sponge]]s and [[placozoa]]ns—animals have bodies that are differentiated into [[biological tissue|tissues]]. These include [[muscle]]s, which are able to contract and control locomotion, and a [[nervous system]], which sends and processes signals. There is also typically an internal [[digestion|digestive]] chamber. The eukaryotic cells possessed by all animals are surrounded by a characteristic extracellular matrix composed of [[collagen]] and elastic [[glycoprotein]]s. This may be calcified to form structures like [[ |
With a few exceptions—most notably the two [[Phylum|phyla]] consisting of [[sponge]]s and [[placozoa]]ns—animals have bodies that are differentiated into [[biological tissue|tissues]]. These include [[muscle]]s, which are able to contract and control locomotion, and a [[nervous system]], which sends and processes signals. There is also typically an internal [[digestion|digestive]] chamber. The eukaryotic cells possessed by all animals are surrounded by a characteristic extracellular matrix composed of [[collagen]] and elastic [[glycoprotein]]s. This may be calcified to form structures like [[Exoskeleton|shells]], [[bone]]s, and [[spicule (sponge)|spicules]], a framework upon which cells can move about and be reorganized during development and maturation, and which supports the complex anatomy required for mobility.{{Citation needed|date=August 2024|reason=Are there unicellular animals?}} |
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==Human interrelationship== |
==Human interrelationship== |
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{{Human timeline}} |
{{Human timeline}} |
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[[File:Na Pali Coast - Kauai.jpg|thumb|left|Despite their natural beauty, the secluded valleys along the [[Na Pali Coast]] in Hawaii are heavily modified by introduced [[invasive species]] such as [[She-oak]].]] |
[[File:Na Pali Coast - Kauai.jpg|thumb|left|Despite their natural beauty, the secluded valleys along the [[Na Pali Coast]] in Hawaii are heavily modified by introduced [[invasive species]] such as [[She-oak]].]] |
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Although [[humans]] comprise only a minuscule proportion of the total living [[biomass]] on Earth, the [[human impact on the environment|human effect on nature]] is disproportionately large. Because of the extent of human influence, the boundaries between what humans regard as nature and "made environments" is not clear cut except at the extremes. Even at the extremes, the amount of natural environment that is free of discernible human influence is diminishing at an increasingly rapid pace. |
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===Human impact=== |
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The development of [[technology]] by the human race has allowed the greater [[exploitation of natural resources]] and has helped to alleviate some of the risk from [[natural hazards]]. In spite of this progress, however, the fate of human [[civilization]] remains closely linked to changes in the environment. There exists a highly complex [[feedback loop]] between the use of advanced technology and changes to the environment that are only slowly becoming understood.<ref>{{cite web|title=Feedback Loops in Global Climate Change Point to a Very Hot 21st Century|website=Science Daily|date=May 22, 2006|url=http://www.lbl.gov/Science-Articles/Archive/ESD-feedback-loops.html|accessdate=January 7, 2007|archive-url=https://web.archive.org/web/20061208131415/http://www.lbl.gov/Science-Articles/Archive/ESD-feedback-loops.html|archive-date=December 8, 2006|url-status=live|df=mdy-all}}</ref> Man-made threats to the Earth's natural environment include pollution, [[deforestation]], and disasters such as oil spills. Humans have contributed to the [[extinction]] of many plants and animals. |
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Although [[humans]] comprise a minuscule proportion of the total living [[Biomass (ecology)|biomass]] on Earth, the [[human impact on the environment|human effect on nature]] is disproportionately large. Because of the extent of human influence, the boundaries between what humans regard as nature and "made environments" is not clear cut except at the extremes. Even at the extremes, the amount of natural environment that is free of discernible human influence is diminishing at an increasingly rapid pace. A 2020 study published in ''[[Nature (journal)|Nature]]'' found that anthropogenic mass (human-made materials) outweighs all living biomass on earth, with [[Plastic pollution|plastic]] alone exceeding the mass of all land and marine animals combined.<ref>{{cite journal |last1=Elhacham|first1=Emily |last2=Ben-Uri |first2=Liad |display-authors=etal. |date=2020|title=Global human-made mass exceeds all living biomass |journal=Nature |volume=588 |issue=7838 |pages=442–444 |doi=10.1038/s41586-020-3010-5|pmid=33299177 |bibcode=2020Natur.588..442E |s2cid=228077506 }}</ref> And according to a 2021 study published in ''Frontiers in Forests and Global Change'', only about 3% of the planet's terrestrial surface is ecologically and [[fauna]]lly intact, with a low human footprint and healthy populations of native animal species.<ref>{{cite news |last=Carrington |first=Damian |date=April 15, 2021 |title=Just 3% of world's ecosystems remain intact, study suggests |url=https://www.theguardian.com/environment/2021/apr/15/just-3-of-worlds-ecosystems-remain-intact-study-suggests |work=The Guardian |location= |access-date=April 16, 2021 |archive-date=November 24, 2021 |archive-url=https://web.archive.org/web/20211124133706/https://www.theguardian.com/environment/2021/apr/15/just-3-of-worlds-ecosystems-remain-intact-study-suggests |url-status=live }}</ref><ref>{{cite journal |last1=Plumptre|first1=Andrew J. |last2=Baisero |first2=Daniele |display-authors=etal. |date=2021 |title=Where Might We Find Ecologically Intact Communities? |url= |journal=Frontiers in Forests and Global Change |volume=4 |issue= |page=626635 |doi=10.3389/ffgc.2021.626635|bibcode=2021FrFGC...4.6635P |doi-access=free |hdl=10261/242175 |hdl-access=free }}</ref> Philip Cafaro, professor of philosophy at the School of Global Environmental Sustainability at [[Colorado State University]], wrote in 2022 that "the cause of global biodiversity loss is clear: other species are being displaced by a rapidly growing human economy."<ref>{{cite journal |last1= Cafaro|first1=Philip|date=2022 |title=Reducing Human Numbers and the Size of our Economies is Necessary to Avoid a Mass Extinction and Share Earth Justly with Other Species|url=https://www.researchgate.net/publication/359182950|journal=Philosophia|volume=50 |issue= 5|pages=2263–2282 |doi=10.1007/s11406-022-00497-w|s2cid=247433264 |access-date=}}</ref> |
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The development of [[technology]] by the human race has allowed the greater [[exploitation of natural resources]] and has helped to alleviate some of the risk from [[natural hazards]]. In spite of this progress, however, the fate of human [[civilization]] remains closely linked to changes in the environment. There exists a highly complex [[feedback loop]] between the use of advanced technology and changes to the environment that are only slowly becoming understood.<ref>{{cite web|title=Feedback Loops in Global Climate Change Point to a Very Hot 21st Century|website=Science Daily|date=May 22, 2006|url=http://www.lbl.gov/Science-Articles/Archive/ESD-feedback-loops.html|access-date=January 7, 2007|archive-url=https://web.archive.org/web/20061208131415/http://www.lbl.gov/Science-Articles/Archive/ESD-feedback-loops.html|archive-date=December 8, 2006|url-status=dead|df=mdy-all}}</ref> Human-made threats to the Earth's natural environment include [[pollution]], [[deforestation]], and disasters such as oil spills. Humans have contributed to the [[Holocene extinction|extinction]] of many plants and animals,<ref>{{Cite book |last=Kolbert |first=Elizabeth |author-link=Elizabeth Kolbert |title=The Sixth Extinction: An Unnatural History |title-link=The Sixth Extinction: An Unnatural History |year=2014 |publisher=[[Henry Holt and Company]] |location=New York City |isbn=978-0805092998}}</ref> with roughly 1 million species threatened with extinction within decades.<ref>{{Cite journal|doi=10.1126/science.aax9287|title=Landmark analysis documents the alarming global decline of nature|last=Stokstad|first=Erik|date=5 May 2019|journal=[[Science (journal)|Science]]|s2cid=166478506}}</ref> The [[biodiversity loss|loss of biodiversity]] and ecosystem functions over the last half century have impacted the extent that nature can contribute to human quality of life,<ref>{{cite journal |last1=Brauman |first1=Kate A. |last2=Garibaldi |first2=Lucas A. |date=2020 |title=Global trends in nature's contributions to people |url= |journal=[[Proceedings of the National Academy of Sciences of the United States of America|PNAS]] |volume=117 |issue=51 |pages=32799–32805 |doi=10.1073/pnas.2010473117|pmid=33288690 |pmc=7768808 |bibcode=2020PNAS..11732799B |doi-access=free }}</ref> and continued declines could pose a major threat to the existence of human civilization, unless a rapid course correction is made.<ref>{{cite journal |last1=Bradshaw |first1=Corey J. A. |last2=Ehrlich |first2=Paul R. |last3=Beattie |first3=Andrew |last4=Ceballos |first4=Gerardo |last5=Crist |first5=Eileen |last6=Diamond |first6=Joan |last7=Dirzo |first7=Rodolfo |last8=Ehrlich |first8=Anne H. |last9=Harte |first9=John |last10=Harte |first10=Mary Ellen |last11=Pyke |first11=Graham |last12=Raven |first12=Peter H. |last13=Ripple |first13=William J. |last14=Saltré |first14=Frédérik |last15=Turnbull |first15=Christine |last16=Wackernagel |first16=Mathis |last17=Blumstein |first17=Daniel T. |date=2021 |title=Underestimating the Challenges of Avoiding a Ghastly Future |journal=Frontiers in Conservation Science |volume=1 |issue= |pages= |doi=10.3389/fcosc.2020.615419 |access-date=|doi-access=free }}</ref> The value of natural resources to human society is poorly reflected in [[market failure|market prices]] because except for labour costs the natural resources are available free of charge.{{dubious|reason=equipment/exploration/licensing/lawsuits are costs.|date=November 2024}} This distorts market pricing of natural resources and at the same time leads to underinvestment in our natural assets. The annual global cost of public subsidies that damage nature is conservatively estimated at $4–6 trillion (million million). Institutional protections of these natural goods, such as the oceans and rainforests, are lacking. Governments have not prevented these economic [[externalities]].<ref>UK Government Official Documents, February 2021, [https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/957629/Dasgupta_Review_-_Headline_Messages.pdf "The Economics of Biodiversity: The Dasgupta Review Headline Messages"] {{Webarchive|url=https://web.archive.org/web/20220520070152/https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/957629/Dasgupta_Review_-_Headline_Messages.pdf |date=May 20, 2022 }} p. 2</ref><ref>{{cite news |last=Carrington |first=Damian |date=February 2, 2021 |title=Economics of biodiversity review: what are the recommendations? |url=https://www.theguardian.com/environment/2021/feb/02/economics-of-biodiversity-review-what-are-the-recommendations |work=[[The Guardian]] |location= |access-date=13 November 2021 |archive-date=May 24, 2022 |archive-url=https://web.archive.org/web/20220524182314/https://www.theguardian.com/environment/2021/feb/02/economics-of-biodiversity-review-what-are-the-recommendations |url-status=live }}</ref> |
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Humans employ nature for both leisure and economic activities. The acquisition of natural resources for industrial use remains a sizable component of the world's [[economic system]].<ref>{{Cite web|url=https://knoema.com/zscvyje/natural-resources-contribution-to-gdp|title=Natural Resources contribution to GDP|date=November 2014|website=World Development Indicators (WDI)|archive-url=https://web.archive.org/web/20141223080408/https://knoema.com/zscvyje/natural-resources-contribution-to-gdp|archive-date=December 23, 2014|url-status=dead|access-date=}}</ref><ref>{{cite web|url=https://www.cia.gov/library/publications/the-world-factbook/fields/2012.html|title=GDP – Composition by Sector|publisher=[[Central Intelligence Agency]]|work=[[The World Factbook]]|accessdate=February 19, 2017|archive-url=https://web.archive.org/web/20140522215220/https://www.cia.gov/library/publications/the-world-factbook/fields/2012.html|archive-date=May 22, 2014|url-status=live|df=mdy-all}}</ref> Some activities, such as hunting and fishing, are used for both sustenance and leisure, often by different people. [[Agriculture#History|Agriculture]] was first adopted around the [[9th millennium BCE]]. Ranging from food production to energy, nature influences economic wealth. |
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Humans employ nature for both leisure and economic activities. The acquisition of natural resources for industrial use remains a sizable component of the world's [[economic system]].<ref>{{Cite web|url=https://knoema.com/zscvyje/natural-resources-contribution-to-gdp|title=Natural Resources contribution to GDP|date=November 2014|website=World Development Indicators (WDI)|archive-url=https://web.archive.org/web/20141223080408/https://knoema.com/zscvyje/natural-resources-contribution-to-gdp|archive-date=December 23, 2014|url-status=dead}}</ref><ref>{{cite web|url=https://www.cia.gov/library/publications/the-world-factbook/fields/2012.html|title=GDP – Composition by Sector|publisher=[[Central Intelligence Agency]]|work=[[The World Factbook]]|access-date=February 19, 2017|archive-url=https://web.archive.org/web/20140522215220/https://www.cia.gov/library/publications/the-world-factbook/fields/2012.html|archive-date=May 22, 2014|url-status=dead|df=mdy-all}}</ref> Some activities, such as hunting and fishing, are used for both sustenance and leisure, often by different people. [[Agriculture#History|Agriculture]] was first adopted around the [[9th millennium BCE]]. Ranging from food production to energy, nature influences economic wealth. |
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Although early humans gathered uncultivated plant materials for food and employed the [[medicinal plant|medicinal properties of vegetation]] for healing,<ref>{{cite web|url = http://www.nps.gov/plants/medicinal/plants.htm|title = Plant Conservation Alliance – Medicinal Plant Working Groups Green Medicine|publisher = US National Park Services|accessdate = September 23, 2006|archive-url = https://web.archive.org/web/20061009003035/http://www.nps.gov/plants/medicinal/plants.htm|archive-date = October 9, 2006|url-status=live|df = mdy-all}}</ref> most modern human use of plants is through [[agriculture]]. The [[land conversion|clearance of large tracts]] of land for [[crop]] growth has led to a significant reduction in the amount available of [[forestation]] and [[wetlands]], resulting in the [[loss of habitat]] for many plant and animal species as well as increased [[erosion]].<ref>{{cite web|last = Oosthoek|first = Jan|date = 1999|url = http://www.eh-resources.org/philosophy.html|title = Environmental History: Between Science & Philosophy|publisher = Environmental History Resources|accessdate = December 1, 2006|archive-url = https://web.archive.org/web/20070626085227/http://www.eh-resources.org/philosophy.html|archive-date = June 26, 2007|url-status=live|df = mdy-all}}</ref> |
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Although early humans gathered uncultivated plant materials for food and employed the [[medicinal plant|medicinal properties of vegetation]] for healing,<ref>{{cite web|url = http://www.nps.gov/plants/medicinal/plants.htm|title = Plant Conservation Alliance – Medicinal Plant Working Groups Green Medicine|publisher = US National Park Services|access-date = September 23, 2006|archive-url = https://web.archive.org/web/20061009003035/http://www.nps.gov/plants/medicinal/plants.htm|archive-date = October 9, 2006|url-status=live|df = mdy-all}}</ref> most modern human use of plants is through [[agriculture]]. The [[land conversion|clearance of large tracts]] of land for [[crop]] growth has led to a significant reduction in the amount available of [[forestation]] and [[wetlands]], resulting in the [[loss of habitat]] for many plant and animal species as well as increased [[erosion]].<ref>{{cite web|last = Oosthoek|first = Jan|date = 1999|url = http://www.eh-resources.org/philosophy.html|title = Environmental History: Between Science & Philosophy|publisher = Environmental History Resources|access-date = December 1, 2006|archive-url = https://web.archive.org/web/20070626085227/http://www.eh-resources.org/philosophy.html|archive-date = June 26, 2007|url-status=live|df = mdy-all}}</ref> |
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===Aesthetics and beauty=== |
===Aesthetics and beauty=== |
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[[File:504px-Pinguiculagrandiflora1web.jpg|thumb|left|upright|''[[Pinguicula grandiflora]]'', commonly known as a [[Butterwort]]]] |
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[[File:Cyclamen coum (d.j.b.) 02.jpg|thumb|Aesthetically pleasing flowers]] |
[[File:Cyclamen coum (d.j.b.) 02.jpg|thumb|Aesthetically pleasing flowers]] |
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Beauty in nature has historically been a prevalent theme in art and books, filling large sections of libraries and bookstores. That nature has been depicted and celebrated by so much art, photography, poetry, and other literature shows the strength with which many people associate nature and beauty. Reasons why this association exists, and what the association consists of, are studied by the branch of philosophy called [[aesthetics]]. Beyond certain basic characteristics that many philosophers agree about to explain what is seen as beautiful, the opinions are virtually endless.<ref>{{cite web|url=http://www.wilderness.org/Library/Documents/Beauty_Quotes.cfm |title=On the Beauty of Nature |publisher=The Wilderness Society | |
Beauty in nature has historically been a prevalent theme in art and books, filling large sections of libraries and bookstores. That nature has been depicted and celebrated by so much art, photography, poetry, and other literature shows the strength with which many people associate nature and beauty. Reasons why this association exists, and what the association consists of, are studied by the branch of philosophy called [[aesthetics]]. Beyond certain basic characteristics that many philosophers agree about to explain what is seen as beautiful, the opinions are virtually endless.<ref>{{cite web |url=http://www.wilderness.org/Library/Documents/Beauty_Quotes.cfm |title=On the Beauty of Nature |publisher=The Wilderness Society |access-date=September 29, 2006 |url-status=dead |archive-url=https://web.archive.org/web/20060909220214/http://www.wilderness.org/Library/Documents/Beauty_Quotes.cfm |archive-date=September 9, 2006 }}</ref> Nature and wildness have been important subjects in various eras of world history. An early tradition of [[landscape art]] began in China during the [[Tang Dynasty art|Tang Dynasty]] (618–907). The tradition of representing nature ''as it is'' became one of the aims of [[Chinese painting]] and was a significant influence in Asian art. |
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Although natural wonders are celebrated in the [[Psalms]] and the [[Book of Job]], [[wilderness]] portrayals in art became more prevalent in the 1800s, especially in the works of the [[Romantic movement]]. [[Kingdom of Great Britain|British]] artists [[John Constable]] and [[J. M. W. Turner]] turned their attention to capturing the beauty of the natural world in their paintings. Before that, paintings had been primarily of religious scenes or of human beings. [[William Wordsworth]]'s poetry described the wonder of the natural world, which had formerly been viewed as a threatening place. Increasingly the valuing of nature became an aspect of Western culture.<ref name=History>[http://www.spacesfornature.org/greatspaces/conservation.html History of Conservation] {{Webarchive|url=https://web.archive.org/web/20060708005819/http://www.spacesfornature.org/greatspaces/conservation.html |date=July 8, 2006 }} BC Spaces for Nature. Accessed: May 20, 2006.</ref> This artistic movement also coincided with the [[Transcendentalism|Transcendentalist movement]] in the Western world. A common classical idea of beautiful art involves the word [[mimesis]], the imitation of nature. Also in the realm of ideas about beauty in nature is that the perfect is implied through perfect mathematical [[Substantial form|forms]] and more generally by [[patterns in nature]]. As David Rothenburg writes, "The beautiful is the root of science and the goal of art, the highest possibility that humanity can ever hope to see".<ref>{{cite book | title=Survival of the Beautiful: Art, Science and Evolution | publisher=Bloomsbury | author=Rothenberg, David | isbn=978-1-60819-216-8 | date=2011 | url-access=registration | url=https://archive.org/details/survivalofbeauti0000roth }}</ref>{{rp|281}} |
Although natural wonders are celebrated in the [[Psalms]] and the [[Book of Job]], [[wilderness]] portrayals in art became more prevalent in the 1800s, especially in the works of the [[Romantic movement]]. [[Kingdom of Great Britain|British]] artists [[John Constable]] and [[J. M. W. Turner]] turned their attention to capturing the beauty of the natural world in their paintings. Before that, paintings had been primarily of religious scenes or of human beings. [[William Wordsworth]]'s poetry described the wonder of the natural world, which had formerly been viewed as a threatening place. Increasingly the valuing of nature became an aspect of Western culture.<ref name=History>[http://www.spacesfornature.org/greatspaces/conservation.html History of Conservation] {{Webarchive|url=https://web.archive.org/web/20060708005819/http://www.spacesfornature.org/greatspaces/conservation.html |date=July 8, 2006 }} BC Spaces for Nature. Accessed: May 20, 2006.</ref> This artistic movement also coincided with the [[Transcendentalism|Transcendentalist movement]] in the Western world. A common classical idea of beautiful art involves the word [[mimesis]], the imitation of nature. Also in the realm of ideas about beauty in nature is that the perfect is implied through perfect mathematical [[Substantial form|forms]] and more generally by [[patterns in nature]]. As David Rothenburg writes, "The beautiful is the root of science and the goal of art, the highest possibility that humanity can ever hope to see".<ref>{{cite book | title=Survival of the Beautiful: Art, Science and Evolution | publisher=Bloomsbury | author=Rothenberg, David | isbn=978-1-60819-216-8 | date=2011 | url-access=registration | url=https://archive.org/details/survivalofbeauti0000roth }}</ref>{{rp|281}} |
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[[File:Hydrogen Density Plots.png|thumb|The first few [[hydrogen atom]] [[Atomic orbital|electron orbitals]] shown as cross-sections with color-coded probability density]] |
[[File:Hydrogen Density Plots.png|thumb|The first few [[hydrogen atom]] [[Atomic orbital|electron orbitals]] shown as cross-sections with color-coded probability density]] |
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{{Main|Matter|Energy}} |
{{Main|Matter|Energy}} |
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The [[natural science]]s view matter as obeying certain [[scientific law |laws of nature]] which [[scientists]] seeks to understand.<ref name="COPL">{{cite book|last=Feynman|first=Richard|title=The Character of Physical Law|publisher=Modern Library|date=1965|isbn=978-0-679-60127-2}}</ref> |
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Some fields of science see nature as matter in motion, obeying certain laws of nature which science seeks to understand. For this reason the most fundamental science is generally understood to be "[[physics]]"—the name for which is still recognizable as meaning that it is the "'''''study of nature'''''". |
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Matter is commonly defined as the substance of which physical objects are composed. It constitutes the [[observable universe]]. The visible components of the universe are now believed to compose only 4.9 percent of the total mass. The remainder is believed to consist of 26.8 percent [[cold dark matter]] and 68.3 percent [[dark energy]].<ref name="planck_overview">{{cite journal |title=Planck 2013 results. I. Overview of products and scientific results – Table 9. |journal=[[Astronomy and Astrophysics]] |first1=P. A. R. |last1=Ade |first2=N. |last2=Aghanim |author2-link=Nabila Aghanim|first3=C. |last3=Armitage-Caplan |last4=et al. (Planck Collaboration) |date=March 22, 2013 |arxiv=1303.5062|bibcode = 2014A&A...571A...1P |doi=10.1051/0004-6361/201321529 |volume=571 |pages=A1|s2cid=218716838 }}</ref> The exact arrangement of these components is still unknown and is under intensive investigation by physicists. |
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Matter is commonly defined as the substance of which physical objects are composed. It constitutes the [[observable universe]]. The visible components of the universe are now believed to compose only 4.9 percent of the total mass. The remainder is believed to consist of 26.8 percent [[cold dark matter]] and 68.3 percent [[dark energy]].<ref name="planck_overview">{{cite journal |title=Planck 2013 results. I. Overview of products and scientific results – Table 9. |journal=[[Astronomy and Astrophysics]] |first1=P. A. R. |last1=Ade |first2=N. |last2=Aghanim |first3=C. |last3=Armitage-Caplan |last4=et al. (Planck Collaboration) |date=March 22, 2013 |arxiv=1303.5062|bibcode = 2014A&A...571A...1P |doi=10.1051/0004-6361/201321529 |volume=571 |pages=A1}}</ref> The exact arrangement of these components is still unknown and is under intensive investigation by physicists. |
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The behaviour of matter and energy throughout the observable universe appears to follow well-defined [[physical law]]s. These laws have been employed to produce [[Physical cosmology|cosmological]] models that successfully explain the structure and the evolution of the universe we can observe. The mathematical expressions of the laws of physics employ a set of twenty [[physical constant]]s<ref> |
The behaviour of matter and energy throughout the observable universe appears to follow well-defined [[physical law]]s. These laws have been employed to produce [[Physical cosmology|cosmological]] models that successfully explain the structure and the evolution of the universe we can observe. The mathematical expressions of the laws of physics employ a set of twenty [[physical constant]]s<ref>{{cite web|last = Taylor|first = Barry N.|date = 1971|url = http://www.physics.nist.gov/cuu/Constants/introduction.html|title = Introduction to the constants for nonexperts|publisher = National Institute of Standards and Technology|access-date = January 7, 2007|archive-url = https://web.archive.org/web/20070107012004/http://physics.nist.gov/cuu/Constants/introduction.html|archive-date = January 7, 2007|url-status = dead|df = mdy-all}}</ref> that appear to be static across the observable universe.<ref>{{cite journal|author=Varshalovich, D.A.|author2=Potekhin, A.Y.|author3=Ivanchik, A.V. |name-list-style=amp|title=Testing cosmological variability of fundamental constants|journal=AIP Conference Proceedings|date=2000|volume=506|page=503|arxiv=physics/0004062|doi=10.1063/1.1302777|bibcode=2000AIPC..506..503V|citeseerx=10.1.1.43.6877}}</ref> The values of these constants have been carefully measured, but the reason for their specific values remains a mystery. |
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{{cite web|last = Taylor|first = Barry N.|date = 1971|url = http://www.physics.nist.gov/cuu/Constants/introduction.html|title = Introduction to the constants for nonexperts|publisher = National Institute of Standards and Technology|accessdate = January 7, 2007|archive-url = https://web.archive.org/web/20070107012004/http://physics.nist.gov/cuu/Constants/introduction.html|archive-date = January 7, 2007|url-status=live|df = mdy-all}} |
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</ref> that appear to be static across the observable universe.<ref>{{cite journal|author=Varshalovich, D.A.|author2=Potekhin, A.Y.|author3=Ivanchik, A.V. |last-author-amp=yes|title=Testing cosmological variability of fundamental constants|journal=AIP Conference Proceedings|date=2000|volume=506|page=503|arxiv=physics/0004062|doi=10.1063/1.1302777|bibcode=2000AIPC..506..503V|citeseerx=10.1.1.43.6877}}</ref> The values of these constants have been carefully measured, but the reason for their specific values remains a mystery. |
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==Beyond Earth== |
==Beyond Earth== |
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[[File:Planets2013.jpg|thumb|left|upright=1.3|[[Planet]]s of the [[Solar System]] ''(Sizes to scale, distances and illumination not to scale)'']] |
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[[File:NGC 4414 (NASA-med).jpg|thumb|'''[[NGC 4414]]''' is a spiral galaxy in the constellation [[Coma Berenices]] about 56,000 [[light-year]]s in diameter and approximately 60 million light-years from [[Earth]]]] |
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{{Main|Outer space|Universe|Extraterrestrial life}} |
{{Main|Outer space|Universe|Extraterrestrial life}} |
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Outer space, also simply called ''space'', refers to the relatively empty regions of the [[universe]] outside the [[atmosphere]]s of celestial bodies. ''Outer'' space is used to distinguish it from [[airspace]] (and terrestrial locations). There is no discrete boundary between the [[Earth's atmosphere]] and space, as the atmosphere gradually attenuates with increasing altitude. Outer space within the [[Solar System]] is called [[interplanetary space]], which passes over into [[interstellar medium|interstellar space]] at what is known as the [[heliopause (astronomy)|heliopause]]. |
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[[File:Planets2013.svg|thumb|left|upright=1.3|[[Planet]]s of the [[Solar System]] ''(sizes to scale, distances and illumination not to scale)'']] |
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Outer space is sparsely filled with several dozen types of [[organic chemistry|organic]] [[molecule]]s discovered to date by [[rotational spectroscopy|microwave spectroscopy]], [[cosmic microwave background radiation|blackbody radiation]] left over from the [[Big Bang]] and the origin of the universe, and [[cosmic ray]]s, which include [[ion]]ized [[atomic nucleus|atomic nuclei]] and various [[subatomic particle]]s. There is also some gas, [[Plasma (physics)|plasma]] and [[dust]], and small [[meteor]]s. Additionally, there are signs of human life in outer space today, such as material left over from previous manned and unmanned launches which are a potential hazard to spacecraft. Some of this [[space debris|debris]] re-enters the atmosphere periodically. |
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[[File:NGC 4414 (NASA-med).jpg|thumb|'''[[NGC 4414]]''' is a spiral galaxy in the constellation [[Coma Berenices]] about 56,000 [[light-year]]s in diameter and approximately 60 million light-years from [[Earth]].]] |
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Outer space, also simply called ''space'', refers to the relatively empty regions of the [[Universe]] outside the [[atmosphere]]s of celestial bodies. ''Outer'' space is used to distinguish it from [[airspace]] (and terrestrial locations). There is no discrete boundary between [[atmosphere of Earth|Earth's atmosphere]] and space, as the atmosphere gradually attenuates with increasing altitude. Outer space within the [[Solar System]] is called [[interplanetary medium|interplanetary space]], which passes over into [[interstellar medium|interstellar space]] at what is known as the [[Heliopause (astronomy)|heliopause]]. |
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Although the Earth is the only body within the solar system known to support life, evidence suggests that in the distant past the planet [[Mars]] possessed bodies of liquid water on the surface.<ref>{{cite journal|author = Bibring, J |display-authors=etal|title = Global mineralogical and aqueous mars history derived from OMEGA/Mars Express data|journal = Science|volume = 312|issue = 5772|pages = 400–04|date = 2006|pmid = 16627738|doi = 10.1126/science.1122659|bibcode = 2006Sci...312..400B}}</ref> For a brief period in Mars' history, it may have also been capable of forming life. At present though, most of the water remaining on Mars is frozen. |
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If life exists at all on Mars, it is most likely to be located underground where liquid water can still exist.<ref>{{cite web|first = Tariq|last = Malik|date = March 8, 2005|url = http://www.nbcnews.com/id/7129347|title = Hunt for Mars life should go underground|publisher = Space.com via NBC News|accessdate = September 4, 2006|df = mdy-all}}</ref> |
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Outer space is sparsely filled with several dozen types of [[organic chemistry|organic]] [[molecule]]s discovered to date by [[rotational spectroscopy|microwave spectroscopy]], [[cosmic microwave background|blackbody radiation]] left over from the [[Big Bang]] and the origin of the universe, and [[cosmic ray]]s, which include [[ion]]ized [[atomic nucleus|atomic nuclei]] and various [[subatomic particle]]s. There is also some gas, [[plasma (physics)|plasma]] and [[dust]], and small [[meteor]]s. Additionally, there are signs of human life in outer space today, such as material left over from previous crewed and uncrewed launches which are a potential hazard to spacecraft. Some of this [[space debris|debris]] re-enters the atmosphere periodically. |
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Conditions on the other terrestrial planets, [[Mercury (planet)|Mercury]] and [[Venus]], appear to be too harsh to support life as we know it. But it has been conjectured that [[Europa (moon)|Europa]], the fourth-largest moon of [[Jupiter]], may possess a sub-surface ocean of liquid water and could potentially host life.<ref>{{cite web|author = Turner, Scott|date = March 2, 1998|url = http://www2.jpl.nasa.gov/galileo/news8.html|title = Detailed Images From Europa Point To Slush Below Surface|publisher = NASA|accessdate = September 28, 2006|archive-url = https://web.archive.org/web/20060929232149/http://www2.jpl.nasa.gov/galileo/news8.html|archive-date = September 29, 2006|url-status=live|df = mdy-all}}</ref> |
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Although Earth is the only body within the [[Solar System]] known to support life, evidence suggests that in the distant past the planet [[Mars]] possessed bodies of liquid water on the surface.<ref>{{cite journal|author = Bibring, J |display-authors=etal|title = Global mineralogical and aqueous mars history derived from OMEGA/Mars Express data|journal = Science|volume = 312|issue = 5772|pages = 400–404|date = 2006|pmid = 16627738|doi = 10.1126/science.1122659|bibcode = 2006Sci...312..400B|s2cid=13968348 |doi-access = }}</ref> For a brief period in Mars' history, it may have also been capable of forming life. At present though, most of the water remaining on Mars is frozen. |
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Astronomers have started to discover extrasolar [[Earth analog]]s – planets that lie in the [[habitable zone]] of space surrounding a [[star]], and therefore could possibly host life as we know it.<ref>Choi, Charles Q. (March 21, 2011) [http://www.space.com/11188-alien-earths-planets-sun-stars.html New Estimate for Alien Earths: 2 Billion in Our Galaxy Alone | Alien Planets, Extraterrestrial Life & Extrasolar Planets | Exoplanets & Kepler Space Telescope] {{Webarchive|url=https://web.archive.org/web/20130703101746/http://www.space.com/11188-alien-earths-planets-sun-stars.html |date=July 3, 2013 }}. Space.com.</ref> |
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If life exists at all on Mars, it is most likely to be located underground where liquid water can still exist.<ref>{{cite web|first = Tariq|last = Malik|date = March 8, 2005|url = http://www.nbcnews.com/id/7129347|title = Hunt for Mars life should go underground|publisher = Space.com via NBC News|access-date = September 4, 2006|df = mdy-all|archive-date = September 30, 2013|archive-url = https://web.archive.org/web/20130930205156/http://www.nbcnews.com/id/7129347/|url-status = dead}}</ref> |
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Conditions on the other terrestrial planets, [[Mercury (planet)|Mercury]] and [[Venus]], appear to be too harsh to support life as we know it. But it has been conjectured that [[Europa (moon)|Europa]], the fourth-largest moon of [[Jupiter]], may possess a sub-surface ocean of liquid water and could potentially host life.<ref>{{cite web|author = Turner, Scott|date = March 2, 1998|url = http://www2.jpl.nasa.gov/galileo/news8.html|title = Detailed Images From Europa Point To Slush Below Surface|publisher = NASA|access-date = September 28, 2006|archive-url = https://web.archive.org/web/20060929232149/http://www2.jpl.nasa.gov/galileo/news8.html|archive-date = September 29, 2006|url-status = dead|df = mdy-all}}</ref> |
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Astronomers have started to discover extrasolar [[Earth analog]]s – planets that lie in the [[circumstellar habitable zone|habitable zone]] of space surrounding a [[star]], and therefore could possibly host life as we know it.<ref>Choi, Charles Q. (March 21, 2011) [http://www.space.com/11188-alien-earths-planets-sun-stars.html New Estimate for Alien Earths: 2 Billion in Our Galaxy Alone | Alien Planets, Extraterrestrial Life & Extrasolar Planets | Exoplanets & Kepler Space Telescope] {{Webarchive|url=https://web.archive.org/web/20130703101746/http://www.space.com/11188-alien-earths-planets-sun-stars.html |date=July 3, 2013 }}. Space.com.</ref> |
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==See also== |
==See also== |
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{{Portal|Animals|Astronomy|Biology|Earth sciences|Ecology|Environment|Plants|Science|Solar System|Stars|Trees|Water|Weather|World}} |
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{{Wikipedia books}} |
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{{div col|colwidth=20em}} |
{{div col|colwidth=20em}} |
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* [[Biophilic design]] |
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* [[Force of nature (disambiguation)|Force of nature]] |
* [[Force of nature (disambiguation)|Force of nature]] |
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* [[Human nature]] |
* [[Human nature]] |
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* [[Natural building]] |
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* [[Natural history]] |
* [[Natural history]] |
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* [[Naturalism (disambiguation)|Naturalism]] |
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* [[Natural landscape]] |
* [[Natural landscape]] |
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* [[Natural law]] |
* [[Natural law]] |
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* [[Natural science]] |
* [[Natural science]] |
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* [[Natural theology]] |
* [[Natural theology]] |
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* [[Naturalism (disambiguation)|Naturalism]] |
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* [[Nature reserve]] |
* [[Nature reserve]] |
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* [[Template:Nature timeline|Nature timeline]] |
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* [[Nature versus nurture]] |
* [[Nature versus nurture]] |
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* [[Nature worship]] |
* [[Nature worship]] |
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* [[Nature-based solutions]] |
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* [[Naturism]] |
* [[Naturism]] |
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* [[Rewilding (conservation biology)|Rewilding]] |
* [[Rewilding (conservation biology)|Rewilding]] |
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'''Media:''' |
'''Media:''' |
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* ''[[National Wildlife (magazine)|National Wildlife]]'', a publication of the National Wildlife Federation |
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* ''[[Natural History (Pliny)|Natural History]]'', by [[Pliny the Elder]] |
* ''[[Natural History (Pliny)|Natural History]]'', by [[Pliny the Elder]] |
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* ''[[Natural World (TV series)|Natural World]]'' (TV series) |
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* ''[[Nature (essay)|Nature]]'', by [[Ralph Waldo Emerson]] |
* ''[[Nature (essay)|Nature]]'', by [[Ralph Waldo Emerson]] |
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* ''[[Nature (journal)|Nature]]'', a prominent scientific journal |
* ''[[Nature (journal)|Nature]]'', a prominent scientific journal |
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* ''[[National Wildlife (magazine)|National Wildlife]]'', a publication of the National Wildlife Federation |
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* ''[[Nature (TV series)|Nature]]'' (TV series) |
* ''[[Nature (TV series)|Nature]]'' (TV series) |
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* ''[[ |
* ''[[The World We Live In (Life magazine)]]'' |
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'''Organizations:''' |
'''Organizations:''' |
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* [[The Nature Conservancy]] |
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* [[Nature Detectives]] |
* [[Nature Detectives]] |
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* [[The Nature Conservancy]] |
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'''Philosophy:''' |
'''Philosophy:''' |
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* [[Balance of nature]] (biological fallacy), a discredited concept of natural equilibrium in predator–prey dynamics |
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* [[Mother Nature]] |
* [[Mother Nature]] |
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* [[Naturalism (philosophy)|Naturalism]], any of several philosophical stances, typically those descended from [[materialism]] and [[pragmatism]] that do not distinguish the supernatural from nature;<ref>Papineau, David (2016) [https://plato.stanford.edu/archives/win2016/entries/naturalism/ "Naturalism"], The Stanford Encyclopedia of Philosophy, Edward N. Zalta (ed.), {{Webarchive|url=https://web.archive.org/web/20190401175926/https://plato.stanford.edu/archives/win2016/entries/naturalism/ |date=April 1, 2019 }}></ref> this includes the ''methodological naturalism'' of natural science, which makes the [[methodology|methodological]] assumption that [[observation|observable]] events in nature are explained only by natural causes, without assuming either the existence or non-existence of the supernatural |
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* [[Nature (philosophy)]] |
* [[Nature (philosophy)]] |
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* [[Naturalism (philosophy)|Naturalism]], any of several philosophical stances, typically those descended from [[materialism]] and [[pragmatism]] that do not distinguish the supernatural from nature;<ref>Papineau, David, "Naturalism", The Stanford Encyclopedia of Philosophy (Winter 2016 Edition), Edward N. Zalta (ed.), URL = <https://plato.stanford.edu/archives/win2016/entries/naturalism/ {{Webarchive|url=https://web.archive.org/web/20190401175926/https://plato.stanford.edu/archives/win2016/entries/naturalism/ |date=April 1, 2019 }}></ref> this includes the ''methodological naturalism'' of natural science, which makes the [[methodology|methodological]] assumption that [[observation|observable]] events in nature are explained only by natural causes, without assuming either the existence or non-existence of the supernatural |
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* [[Balance of nature]] (biological fallacy), a discredited concept of natural equilibrium in predator–prey dynamics |
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==Notes and references== |
==Notes and references== |
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== Further reading == |
== Further reading == |
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* {{ |
* {{Cite journal |last1=Droz |first1=Layna |last2=Chen |first2=Hsun-Mei |last3=Chu |first3=Hung-Tao |last4=Fajrini |first4=Rika |last5=Imbong |first5=Jerry |last6=Jannel |first6=Romaric |last7=Komatsubara |first7=Orika |last8=Lagasca-Hiloma |first8=Concordia Marie A. |last9=Meas |first9=Chansatya |last10=Nguyen |first10=Duy Hung |last11=Sherpa |first11=Tshering Ongmu |display-authors=1 |date=May 31, 2022 |title=Exploring the diversity of conceptualizations of nature in East and South-East Asia |journal=Humanities and Social Sciences Communications |volume=9 |issue=1 |pages=1–12 |doi=10.1057/s41599-022-01186-5 |issn=2662-9992 |doi-access=free}} |
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* {{cite journal |last1=Ducarme |first1=Frédéric |last2=Couvet |first2=Denis |year=2020 |title=What does 'nature' mean? |journal=[[Palgrave Communications]] |volume=6 |issue=14 |publisher=[[Springer Nature]] |doi=10.1057/s41599-020-0390-y |doi-access=free }} |
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* {{cite book |last1=Emerson |first1=Ralph W. |year=1836 |title=Nature |location=Boston|publisher=James Munroe & Co }} |
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* Farber, Paul Lawrence (2000), ''Finding Order in Nature: The Naturalist Tradition from Linnaeus to E. O. Wilson''. Johns Hopkins University Press: Baltimore. |
* Farber, Paul Lawrence (2000), ''Finding Order in Nature: The Naturalist Tradition from Linnaeus to E. O. Wilson''. Johns Hopkins University Press: Baltimore. |
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* {{cite web|url=https://theconversation.com/have-we-reached-the-end-of-nature-our-relationship-with-the-environment-is-in-crisis-206278|title=Have we reached the end of nature? Our relationship with the environment is in crisis|last=Lynch|first=Derek|date=October 17, 2023|website=[[The Conversation (website)|The Conversation]]|publisher=|access-date=|quote=|archive-date=October 22, 2023|archive-url=https://web.archive.org/web/20231022040316/https://theconversation.com/have-we-reached-the-end-of-nature-our-relationship-with-the-environment-is-in-crisis-206278|url-status=live}} |
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* {{cite book |last1=Worster |first1=D. |year=1994 |title=Nature's Economy: A History of Ecological Ideas |location=Cambridge |publisher=[[Cambridge University Press]] |isbn=}} |
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* {{cite book |last1= |
* {{cite book |last1=Naddaf|first1=Gerard |year=2006 |title=The Greek Concept of Nature|location=Albany|publisher=SUNY Press }} |
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* {{cite journal |last1=Piccolo|first1=John J. |last2=Taylor|first2=Bron |last3=Washington|first3=Haydn |last4=Kopnina|first4=Helen |last5=Gray|first5=Joe |last6=Alberro|first6=Heather |last7= Orlikowska|first7=Ewa|date=2022 |title="Nature's contributions to people" and peoples' moral obligations to nature|url= |journal=[[Biological Conservation (journal)|Biological Conservation]]|volume=270 |issue= |page=109572 |doi=10.1016/j.biocon.2022.109572|s2cid=248769087 |doi-access=free|bibcode=2022BCons.27009572P }} |
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* {{cite book |last1=Naddaf|first1=Gerard |year=2006 |title=The Greek Concept of Nature|location=Albany|publisher=SUNY Press |isbn=}} |
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* {{cite book |last1=Worster |first1=D. |year=1994 |title=Nature's Economy: A History of Ecological Ideas |location=Cambridge |publisher=[[Cambridge University Press]] }} |
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==External links== |
==External links== |
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* [http://www.iucnredlist.org/ The IUCN Red List of Threatened Species (iucnredlist.org)] |
* [http://www.iucnredlist.org/ The IUCN Red List of Threatened Species (iucnredlist.org)] {{Webarchive|url=https://web.archive.org/web/20140627000000/http://www.iucnredlist.org/ |date=June 27, 2014 }} |
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* {{cite web |url=https://www.encyclopedie-environnement.org/en/life/what-is-nature/ |title=What is nature? |last1=Ducarme |first1=Frédéric |date=3 January 2021 |website=Encyclopedia of the Environment |access-date= |archive-date=April 23, 2021 |archive-url=https://web.archive.org/web/20210423163751/https://www.encyclopedie-environnement.org/en/life/what-is-nature/ |url-status=live }} |
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* [http://www.wild.org/ The Wild Foundation – The heart of the global wilderness conservation movement (wild.org)] |
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* [http://www.fauna-flora.org/ Fauna & Flora International is taking decisive action to help save the world’s wild species and spaces (fauna-flora.org)] |
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* [http://www.eurowildlife.org European Wildlife is a Pan-European non-profit organization dedicated to nature preservation and environmental protection (eurowildlife.org)] |
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* [http://www.nature.com/nature/index.html Nature Journal (nature.com)] |
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* [http://www.nationalgeographic.com/ The National Geographic Society (nationalgeographic.com)] |
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* [https://archive.today/20160426231847/http://www.arkive.org/ Record of life on Earth (arkive.org)] |
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* [http://www.bbc.co.uk/sn/ BBC – Science and Nature (bbc.co.uk)] |
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* [https://www.pbs.org/topics/science-nature/ PBS – Science and Nature (pbs.org)] |
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* [https://www.sciencedaily.com/news/plants_animals/ Science Daily (sciencedaily.com)] |
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* [http://ec.europa.eu/environment/nature/index_en.htm European Commission – Nature and Biodiversity (ec.europa.eu)] |
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* [http://www.nhm.ac.uk/ Natural History Museum (.nhm.ac.uk)] |
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* [http://eol.org/ Encyclopedia of Life (eol.org)]. |
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* [https://web.archive.org/web/20090506215842/http://science.gov/browse/w_123.htm Science.gov – Environment & Environmental Quality]. |
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* [https://web.archive.org/web/20170606165757/https://www.check123.com/categories/nature Check123 – Nature videos (Check123.com)] |
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* [http://www.naturelyrics.com/pages/articles/nature_photography/nature_in_nature_photography.html Art of the Nature Timelines] |
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* [http://www.bbc.co.uk/programmes/p005490t Nature], BBC Radio 4 discussion with Jonathan Bate, Roger Scruton & Karen Edwards (''In Our Time'', July 10, 2003) |
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[[Category:Nature| ]] |
[[Category:Nature| ]] |
Latest revision as of 21:06, 17 December 2024
Nature is an inherent character or constitution,[1] particularly of the ecosphere or the universe as a whole. In this general sense nature refers to the laws, elements and phenomena of the physical world, including life. Although humans are part of nature, human activity or humans as a whole are often described as at times at odds, or outright separate and even superior to nature.[2]
During the advent of modern scientific method in the last several centuries, nature became the passive reality, organized and moved by divine laws.[3][4] With the Industrial Revolution, nature increasingly became seen as the part of reality deprived from intentional intervention: it was hence considered as sacred by some traditions (Rousseau, American transcendentalism) or a mere decorum for divine providence or human history (Hegel, Marx). However, a vitalist vision of nature, closer to the pre-Socratic one, got reborn at the same time, especially after Charles Darwin.[2]
Within the various uses of the word today, "nature" often refers to geology and wildlife. Nature can refer to the general realm of living beings, and in some cases to the processes associated with inanimate objects—the way that particular types of things exist and change of their own accord, such as the weather and geology of the Earth. It is often taken to mean the "natural environment" or wilderness—wild animals, rocks, forest, and in general those things that have not been substantially altered by human intervention, or which persist despite human intervention. For example, manufactured objects and human interaction generally are not considered part of nature, unless qualified as, for example, "human nature" or "the whole of nature". This more traditional concept of natural things that can still be found today implies a distinction between the natural and the artificial, with the artificial being understood as that which has been brought into being by a human consciousness or a human mind. Depending on the particular context, the term "natural" might also be distinguished from the unnatural or the supernatural.[2]
Etymology
The word nature is borrowed from the Old French nature and is derived from the Latin word natura, or "essential qualities, innate disposition", and in ancient times, literally meant "birth".[5] In ancient philosophy, natura is mostly used as the Latin translation of the Greek word physis (φύσις), which originally related to the intrinsic characteristics of plants, animals, and other features of the world to develop of their own accord.[6][7] The concept of nature as a whole, the physical universe, is one of several expansions of the original notion;[2] it began with certain core applications of the word φύσις by pre-Socratic philosophers (though this word had a dynamic dimension then, especially for Heraclitus), and has steadily gained currency ever since.
Earth
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Earth is the only planet known to support life, and its natural features are the subject of many fields of scientific research. Within the Solar System, it is third closest to the Sun; it is the largest terrestrial planet and the fifth largest overall. Its most prominent climatic features are its two large polar regions, two relatively narrow temperate zones, and a wide equatorial tropical to subtropical region.[8] Precipitation varies widely with location, from several metres of water per year to less than a millimetre. 71 percent of the Earth's surface is covered by salt-water oceans. The remainder consists of continents and islands, with most of the inhabited land in the Northern Hemisphere.
Earth has evolved through geological and biological processes that have left traces of the original conditions. The outer surface is divided into several gradually migrating tectonic plates. The interior remains active, with a thick layer of plastic mantle and an iron-filled core that generates a magnetic field. This iron core is composed of a solid inner phase, and a fluid outer phase. Convective motion in the core generates electric currents through dynamo action, and these, in turn, generate the geomagnetic field.
The atmospheric conditions have been significantly altered from the original conditions by the presence of life-forms,[9] which create an ecological balance that stabilizes the surface conditions. Despite the wide regional variations in climate by latitude and other geographic factors, the long-term average global climate is quite stable during interglacial periods,[10] and variations of a degree or two of average global temperature have historically had major effects on the ecological balance, and on the actual geography of the Earth.[11][12]
Geology
Geology is the science and study of the solid and liquid matter that constitutes the Earth. The field of geology encompasses the study of the composition, structure, physical properties, dynamics, and history of Earth materials, and the processes by which they are formed, moved, and changed. The field is a major academic discipline, and is also important for mineral and hydrocarbon extraction, knowledge about and mitigation of natural hazards, some Geotechnical engineering fields, and understanding past climates and environments.
Geological evolution
The geology of an area evolves through time as rock units are deposited and inserted and deformational processes change their shapes and locations.
Rock units are first emplaced either by deposition onto the surface or intrude into the overlying rock. Deposition can occur when sediments settle onto the surface of the Earth and later lithify into sedimentary rock, or when as volcanic material such as volcanic ash or lava flows, blanket the surface. Igneous intrusions such as batholiths, laccoliths, dikes, and sills, push upwards into the overlying rock, and crystallize as they intrude.
After the initial sequence of rocks has been deposited, the rock units can be deformed and/or metamorphosed. Deformation typically occurs as a result of horizontal shortening, horizontal extension, or side-to-side (strike-slip) motion. These structural regimes broadly relate to convergent boundaries, divergent boundaries, and transform boundaries, respectively, between tectonic plates.
Historical perspective
Earth is estimated to have formed 4.54 billion years ago from the solar nebula, along with the Sun and other planets.[13] The Moon formed roughly 20 million years later. Initially molten, the outer layer of the Earth cooled, resulting in the solid crust. Outgassing and volcanic activity produced the primordial atmosphere. Condensing water vapor, most or all of which came from ice delivered by comets, produced the oceans and other water sources.[14] The highly energetic chemistry is believed to have produced a self-replicating molecule around 4 billion years ago.[15]
Continents formed, then broke up and reformed as the surface of Earth reshaped over hundreds of millions of years, occasionally combining to make a supercontinent. Roughly 750 million years ago, the earliest known supercontinent Rodinia, began to break apart. The continents later recombined to form Pannotia which broke apart about 540 million years ago, then finally Pangaea, which broke apart about 180 million years ago.[17]
During the Neoproterozoic era, freezing temperatures covered much of the Earth in glaciers and ice sheets. This hypothesis has been termed the "Snowball Earth", and it is of particular interest as it precedes the Cambrian explosion in which multicellular life forms began to proliferate about 530–540 million years ago.[18]
Since the Cambrian explosion there have been five distinctly identifiable mass extinctions.[19] The last mass extinction occurred some 66 million years ago, when a meteorite collision probably triggered the extinction of the non-avian dinosaurs and other large reptiles, but spared small animals such as mammals. Over the past 66 million years, mammalian life diversified.[20]
Several million years ago, a species of small African ape gained the ability to stand upright.[16] The subsequent advent of human life, and the development of agriculture and further civilization allowed humans to affect the Earth more rapidly than any previous life form, affecting both the nature and quantity of other organisms as well as global climate. By comparison, the Great Oxygenation Event, produced by the proliferation of algae during the Siderian period, required about 300 million years to culminate.
The present era is classified as part of a mass extinction event, the Holocene extinction event, the fastest ever to have occurred.[21][22] Some, such as E. O. Wilson of Harvard University, predict that human destruction of the biosphere could cause the extinction of one-half of all species in the next 100 years.[23] The extent of the current extinction event is still being researched, debated and calculated by biologists.[24][25][26]
Atmosphere, climate, and weather
The Earth's atmosphere is a key factor in sustaining the ecosystem. The thin layer of gases that envelops the Earth is held in place by gravity. Air is mostly nitrogen, oxygen, water vapor, with much smaller amounts of carbon dioxide, argon, etc. The atmospheric pressure declines steadily with altitude. The ozone layer plays an important role in depleting the amount of ultraviolet (UV) radiation that reaches the surface. As DNA is readily damaged by UV light, this serves to protect life at the surface. The atmosphere also retains heat during the night, thereby reducing the daily temperature extremes.
Terrestrial weather occurs almost exclusively in the lower part of the atmosphere, and serves as a convective system for redistributing heat.[27] Ocean currents are another important factor in determining climate, particularly the major underwater thermohaline circulation which distributes heat energy from the equatorial oceans to the polar regions. These currents help to moderate the differences in temperature between winter and summer in the temperate zones. Also, without the redistributions of heat energy by the ocean currents and atmosphere, the tropics would be much hotter, and the polar regions much colder.
Weather can have both beneficial and harmful effects. Extremes in weather, such as tornadoes or hurricanes and cyclones, can expend large amounts of energy along their paths, and produce devastation. Surface vegetation has evolved a dependence on the seasonal variation of the weather, and sudden changes lasting only a few years can have a dramatic effect, both on the vegetation and on the animals which depend on its growth for their food.
Climate is a measure of the long-term trends in the weather. Various factors are known to influence the climate, including ocean currents, surface albedo, greenhouse gases, variations in the solar luminosity, and changes to the Earth's orbit. Based on historical and geological records, the Earth is known to have undergone drastic climate changes in the past, including ice ages.
The climate of a region depends on a number of factors, especially latitude. A latitudinal band of the surface with similar climatic attributes forms a climate region. There are a number of such regions, ranging from the tropical climate at the equator to the polar climate in the northern and southern extremes. Weather is also influenced by the seasons, which result from the Earth's axis being tilted relative to its orbital plane. Thus, at any given time during the summer or winter, one part of the Earth is more directly exposed to the rays of the sun. This exposure alternates as the Earth revolves in its orbit. At any given time, regardless of season, the Northern and Southern Hemispheres experience opposite seasons.
Weather is a chaotic system that is readily modified by small changes to the environment, so accurate weather forecasting is limited to only a few days.[28] Overall, two things are happening worldwide: (1) temperature is increasing on the average; and (2) regional climates have been undergoing noticeable changes.[29]
Water on Earth
Water is a chemical substance that is composed of hydrogen and oxygen (H2O) and is vital for all known forms of life.[30] In typical usage, "water" refers only to its liquid form, but it also has a solid state, ice, and a gaseous state, water vapor, or steam. Water covers 71% of the Earth's surface.[31] On Earth, it is found mostly in oceans and other large bodies of water, with 1.6% of water below ground in aquifers and 0.001% in the air as vapor, clouds, and precipitation.[32][33] Oceans hold 97% of surface water, glaciers, and polar ice caps 2.4%, and other land surface water such as rivers, lakes, and ponds 0.6%. Additionally, a minute amount of the Earth's water is contained within biological bodies and manufactured products.
Oceans
An ocean is a major body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface (an area of some 361 million square kilometers) is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas. More than half of this area is over 3,000 meters (9,800 feet) deep. Average oceanic salinity is around 35 parts per thousand (ppt) (3.5%), and nearly all seawater has a salinity in the range of 30 to 38 ppt. Though generally recognized as several 'separate' oceans, these waters comprise one global, interconnected body of salt water often referred to as the World Ocean or global ocean.[34][35] This concept of a global ocean as a continuous body of water with relatively free interchange among its parts is of fundamental importance to oceanography.[36]
The major oceanic divisions are defined in part by the continents, various archipelagos, and other criteria: these divisions are (in descending order of size) the Pacific Ocean, the Atlantic Ocean, the Indian Ocean, the Southern Ocean, and the Arctic Ocean. Smaller regions of the oceans are called seas, gulfs, bays and other names. There are also salt lakes, which are smaller bodies of landlocked saltwater that are not interconnected with the World Ocean. Two notable examples of salt lakes are the Aral Sea and the Great Salt Lake.
Lakes
A lake (from Latin word lacus) is a terrain feature (or physical feature), a body of liquid on the surface of a world that is localized to the bottom of basin (another type of landform or terrain feature; that is, it is not global) and moves slowly if it moves at all. On Earth, a body of water is considered a lake when it is inland, not part of the ocean, is larger and deeper than a pond, and is fed by a river.[37][38] The only world other than Earth known to harbor lakes is Titan, Saturn's largest moon, which has lakes of ethane, most likely mixed with methane. It is not known if Titan's lakes are fed by rivers, though Titan's surface is carved by numerous river beds. Natural lakes on Earth are generally found in mountainous areas, rift zones, and areas with ongoing or recent glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers. In some parts of the world, there are many lakes because of chaotic drainage patterns left over from the last ice age. All lakes are temporary over geologic time scales, as they will slowly fill in with sediments or spill out of the basin containing them.
Ponds
A pond is a body of standing water, either natural or human-made, that is usually smaller than a lake. A wide variety of human-made bodies of water are classified as ponds, including water gardens designed for aesthetic ornamentation, fish ponds designed for commercial fish breeding, and solar ponds designed to store thermal energy. Ponds and lakes are distinguished from streams via current speed. While currents in streams are easily observed, ponds and lakes possess thermally driven micro-currents and moderate wind driven currents. These features distinguish a pond from many other aquatic terrain features, such as stream pools and tide pools.
Rivers
A river is a natural watercourse,[39] usually freshwater, flowing towards an ocean, a lake, a sea or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including stream, creek, brook, rivulet, and rill; there is no general rule that defines what can be called a river. Many names for small rivers are specific to geographic location; one example is Burn in Scotland and North-east England. Sometimes a river is said to be larger than a creek, but this is not always the case, due to vagueness in the language.[40] A river is part of the hydrological cycle. Water within a river is generally collected from precipitation through surface runoff, groundwater recharge, springs, and the release of stored water in natural ice and snowpacks (i.e., from glaciers).
Streams
A stream is a flowing body of water with a current, confined within a bed and stream banks. In the United States, a stream is classified as a watercourse less than 60 feet (18 metres) wide. Streams are important as conduits in the water cycle, instruments in groundwater recharge, and they serve as corridors for fish and wildlife migration. The biological habitat in the immediate vicinity of a stream is called a riparian zone. Given the status of the ongoing Holocene extinction, streams play an important corridor role in connecting fragmented habitats and thus in conserving biodiversity. The study of streams and waterways in general involves many branches of inter-disciplinary natural science and engineering, including hydrology, fluvial geomorphology, aquatic ecology, fish biology, riparian ecology, and others.
Ecosystems
Ecosystems are composed of a variety of biotic and abiotic components that function in an interrelated way.[42] The structure and composition is determined by various environmental factors that are interrelated. Variations of these factors will initiate dynamic modifications to the ecosystem. Some of the more important components are soil, atmosphere, radiation from the sun, water, and living organisms.
Central to the ecosystem concept is the idea that living organisms interact with every other element in their local environment. Eugene Odum, a founder of ecology, stated: "Any unit that includes all of the organisms (ie: the "community") in a given area interacting with the physical environment so that a flow of energy leads to clearly defined trophic structure, biotic diversity, and material cycles (i.e.: exchange of materials between living and nonliving parts) within the system is an ecosystem."[43] Within the ecosystem, species are connected and dependent upon one another in the food chain, and exchange energy and matter between themselves as well as with their environment.[44] The human ecosystem concept is based on the human/nature dichotomy and the idea that all species are ecologically dependent on each other, as well as with the abiotic constituents of their biotope.[45]
A smaller unit of size is called a microecosystem. For example, a microsystem can be a stone and all the life under it. A macroecosystem might involve a whole ecoregion, with its drainage basin.[46]
Wilderness
Wilderness is generally defined as areas that have not been significantly modified by human activity. Wilderness areas can be found in preserves, estates, farms, conservation preserves, ranches, national forests, national parks, and even in urban areas along rivers, gulches, or otherwise undeveloped areas. Wilderness areas and protected parks are considered important for the survival of certain species, ecological studies, conservation, and solitude. Some nature writers believe wilderness areas are vital for the human spirit and creativity,[47] and some ecologists consider wilderness areas to be an integral part of the Earth's self-sustaining natural ecosystem (the biosphere). They may also preserve historic genetic traits and that they provide habitat for wild flora and fauna that may be difficult or impossible to recreate in zoos, arboretums, or laboratories.
Life
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Although there is no universal agreement on the definition of life, scientists generally accept that the biological manifestation of life is characterized by organization, metabolism, growth, adaptation, response to stimuli, and reproduction.[48] Life may also be said to be simply the characteristic state of organisms.
Present day organisms from viruses to humans possess a self-replicating informational molecule (genome), either DNA or RNA (as in some viruses), and such an informational molecule is probably intrinsic to life. It is likely that the earliest forms of life were based on a self-replicating informational molecule (genome), perhaps RNA[49][50] or a molecule more primitive than RNA or DNA. The specific deoxyribonucleotide/ribonucleotide sequence in each currently extant individual organism contains sequence information that functions to promotes survival, reproduction, and the capacity to acquire resources necessary for reproduction, and such sequences probably emerged early in the evolution of life. Survival functions present early in the evolution of life likely also included genomic sequences that promote the avoidance of damage to the self-replicating molecule and also the capability to repair such damages that do occur. Repair of some genome damages may have involved using information from another similar molecule by a process of recombination (a primitive form of sexual interaction).[51]
Properties common to terrestrial organisms (plants, animals, fungi, protists, archaea, and bacteria) are that they are cellular, carbon-and-water-based with complex organization, having a metabolism, a capacity to grow, respond to stimuli, and reproduce. An entity with these properties is generally considered life. However, not every definition of life considers all of these properties to be essential. Human-made analogs of life may also be considered to be life.
The biosphere is the part of Earth's outer shell—including land, surface rocks, water, air and the atmosphere—within which life occurs, and which biotic processes in turn alter or transform. From the broadest geophysiological point of view, the biosphere is the global ecological system integrating all living beings and their relationships, including their interaction with the elements of the lithosphere (rocks), hydrosphere (water), and atmosphere (air). The entire Earth contains over 75 billion tons (150 trillion pounds or about 6.8×1013 kilograms) of biomass (life), which lives within various environments within the biosphere.[52]
Over nine-tenths of the total biomass on Earth is plant life, on which animal life depends very heavily for its existence.[53] More than 2 million species of plant and animal life have been identified to date,[54] and estimates of the actual number of existing species range from several million to well over 50 million.[55][56][57] The number of individual species of life is constantly in some degree of flux, with new species appearing and others ceasing to exist on a continual basis.[58][59] The total number of species is in rapid decline.[60][61][62]
Evolution
The origin of life on Earth is not well understood, but it is known to have occurred at least 3.5 billion years ago,[65][66][67] during the hadean or archean eons on a primordial Earth that had a substantially different environment than is found at present.[68] These life forms possessed the basic traits of self-replication and inheritable traits. Once life had appeared, the process of evolution by natural selection resulted in the development of ever-more diverse life forms.
Species that were unable to adapt to the changing environment and competition from other life forms became extinct. However, the fossil record retains evidence of many of these older species. Current fossil and DNA evidence shows that all existing species can trace a continual ancestry back to the first primitive life forms.[68]
When basic forms of plant life developed the process of photosynthesis the sun's energy could be harvested to create conditions which allowed for more complex life forms.[69] The resultant oxygen accumulated in the atmosphere and gave rise to the ozone layer. The incorporation of smaller cells within larger ones resulted in the development of yet more complex cells called eukaryotes.[70] Cells within colonies became increasingly specialized, resulting in true multicellular organisms. With the ozone layer absorbing harmful ultraviolet radiation, life colonized the surface of Earth.
Microbes
The first form of life to develop on the Earth were unicellular, and they remained the only form of life until about a billion years ago when multi-cellular organisms began to appear.[71] Microorganisms or microbes are microscopic, and smaller than the human eye can see.[72] Microorganisms can be single-celled, such as Bacteria, Archaea, many Protista, and a minority of Fungi.[73]
These life forms are found in almost every location on the Earth where there is liquid water, including in the Earth's interior.[74] Their reproduction is both rapid and profuse. The combination of a high mutation rate and a horizontal gene transfer[75] ability makes them highly adaptable, and able to survive in new and sometimes very harsh environments, including outer space.[76] They form an essential part of the planetary ecosystem. However, some microorganisms are pathogenic and can post health risk to other organisms.
Viruses are infectious agents, but they are not autonomous life forms, as it is the case for viroids, satellites, DPIs and prions.[77]
Plants and animals
Originally Aristotle divided all living things between plants, which generally do not move fast enough for humans to notice, and animals. In Linnaeus' system, these became the kingdoms Vegetabilia (later Plantae) and Animalia. Since then, it has become clear that the Plantae as originally defined included several unrelated groups, and the fungi and several groups of algae were removed to new kingdoms. However, these are still often considered plants in many contexts. Bacterial life is sometimes included in flora,[78][79] and some classifications use the term bacterial flora separately from plant flora.
Among the many ways of classifying plants are by regional floras, which, depending on the purpose of study, can also include fossil flora, remnants of plant life from a previous era. People in many regions and countries take great pride in their individual arrays of characteristic flora, which can vary widely across the globe due to differences in climate and terrain.
Regional floras commonly are divided into categories such as native flora or agricultural and garden flora. Some types of "native flora" actually have been introduced centuries ago by people migrating from one region or continent to another, and become an integral part of the native, or natural flora of the place to which they were introduced. This is an example of how human interaction with nature can blur the boundary of what is considered nature.
Another category of plant has historically been carved out for weeds. Though the term has fallen into disfavor among botanists as a formal way to categorize "useless" plants, the informal use of the word "weeds" to describe those plants that are deemed worthy of elimination is illustrative of the general tendency of people and societies to seek to alter or shape the course of nature. Similarly, animals are often categorized in ways such as domestic, farm animals, wild animals, pests, etc. according to their relationship to human life.
Animals as a category have several characteristics that generally set them apart from other living things. Animals are eukaryotic and usually multicellular, which separates them from bacteria, archaea, and most protists. They are heterotrophic, generally digesting food in an internal chamber, which separates them from plants and algae. They are also distinguished from plants, algae, and fungi by lacking cell walls.
With a few exceptions—most notably the two phyla consisting of sponges and placozoans—animals have bodies that are differentiated into tissues. These include muscles, which are able to contract and control locomotion, and a nervous system, which sends and processes signals. There is also typically an internal digestive chamber. The eukaryotic cells possessed by all animals are surrounded by a characteristic extracellular matrix composed of collagen and elastic glycoproteins. This may be calcified to form structures like shells, bones, and spicules, a framework upon which cells can move about and be reorganized during development and maturation, and which supports the complex anatomy required for mobility.[citation needed]
Human interrelationship
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Human impact
Although humans comprise a minuscule proportion of the total living biomass on Earth, the human effect on nature is disproportionately large. Because of the extent of human influence, the boundaries between what humans regard as nature and "made environments" is not clear cut except at the extremes. Even at the extremes, the amount of natural environment that is free of discernible human influence is diminishing at an increasingly rapid pace. A 2020 study published in Nature found that anthropogenic mass (human-made materials) outweighs all living biomass on earth, with plastic alone exceeding the mass of all land and marine animals combined.[80] And according to a 2021 study published in Frontiers in Forests and Global Change, only about 3% of the planet's terrestrial surface is ecologically and faunally intact, with a low human footprint and healthy populations of native animal species.[81][82] Philip Cafaro, professor of philosophy at the School of Global Environmental Sustainability at Colorado State University, wrote in 2022 that "the cause of global biodiversity loss is clear: other species are being displaced by a rapidly growing human economy."[83]
The development of technology by the human race has allowed the greater exploitation of natural resources and has helped to alleviate some of the risk from natural hazards. In spite of this progress, however, the fate of human civilization remains closely linked to changes in the environment. There exists a highly complex feedback loop between the use of advanced technology and changes to the environment that are only slowly becoming understood.[84] Human-made threats to the Earth's natural environment include pollution, deforestation, and disasters such as oil spills. Humans have contributed to the extinction of many plants and animals,[85] with roughly 1 million species threatened with extinction within decades.[86] The loss of biodiversity and ecosystem functions over the last half century have impacted the extent that nature can contribute to human quality of life,[87] and continued declines could pose a major threat to the existence of human civilization, unless a rapid course correction is made.[88] The value of natural resources to human society is poorly reflected in market prices because except for labour costs the natural resources are available free of charge.[dubious – discuss] This distorts market pricing of natural resources and at the same time leads to underinvestment in our natural assets. The annual global cost of public subsidies that damage nature is conservatively estimated at $4–6 trillion (million million). Institutional protections of these natural goods, such as the oceans and rainforests, are lacking. Governments have not prevented these economic externalities.[89][90]
Humans employ nature for both leisure and economic activities. The acquisition of natural resources for industrial use remains a sizable component of the world's economic system.[91][92] Some activities, such as hunting and fishing, are used for both sustenance and leisure, often by different people. Agriculture was first adopted around the 9th millennium BCE. Ranging from food production to energy, nature influences economic wealth.
Although early humans gathered uncultivated plant materials for food and employed the medicinal properties of vegetation for healing,[93] most modern human use of plants is through agriculture. The clearance of large tracts of land for crop growth has led to a significant reduction in the amount available of forestation and wetlands, resulting in the loss of habitat for many plant and animal species as well as increased erosion.[94]
Aesthetics and beauty
Beauty in nature has historically been a prevalent theme in art and books, filling large sections of libraries and bookstores. That nature has been depicted and celebrated by so much art, photography, poetry, and other literature shows the strength with which many people associate nature and beauty. Reasons why this association exists, and what the association consists of, are studied by the branch of philosophy called aesthetics. Beyond certain basic characteristics that many philosophers agree about to explain what is seen as beautiful, the opinions are virtually endless.[95] Nature and wildness have been important subjects in various eras of world history. An early tradition of landscape art began in China during the Tang Dynasty (618–907). The tradition of representing nature as it is became one of the aims of Chinese painting and was a significant influence in Asian art.
Although natural wonders are celebrated in the Psalms and the Book of Job, wilderness portrayals in art became more prevalent in the 1800s, especially in the works of the Romantic movement. British artists John Constable and J. M. W. Turner turned their attention to capturing the beauty of the natural world in their paintings. Before that, paintings had been primarily of religious scenes or of human beings. William Wordsworth's poetry described the wonder of the natural world, which had formerly been viewed as a threatening place. Increasingly the valuing of nature became an aspect of Western culture.[96] This artistic movement also coincided with the Transcendentalist movement in the Western world. A common classical idea of beautiful art involves the word mimesis, the imitation of nature. Also in the realm of ideas about beauty in nature is that the perfect is implied through perfect mathematical forms and more generally by patterns in nature. As David Rothenburg writes, "The beautiful is the root of science and the goal of art, the highest possibility that humanity can ever hope to see".[97]: 281
Matter and energy
The natural sciences view matter as obeying certain laws of nature which scientists seeks to understand.[98] Matter is commonly defined as the substance of which physical objects are composed. It constitutes the observable universe. The visible components of the universe are now believed to compose only 4.9 percent of the total mass. The remainder is believed to consist of 26.8 percent cold dark matter and 68.3 percent dark energy.[99] The exact arrangement of these components is still unknown and is under intensive investigation by physicists.
The behaviour of matter and energy throughout the observable universe appears to follow well-defined physical laws. These laws have been employed to produce cosmological models that successfully explain the structure and the evolution of the universe we can observe. The mathematical expressions of the laws of physics employ a set of twenty physical constants[100] that appear to be static across the observable universe.[101] The values of these constants have been carefully measured, but the reason for their specific values remains a mystery.
Beyond Earth
Outer space, also simply called space, refers to the relatively empty regions of the Universe outside the atmospheres of celestial bodies. Outer space is used to distinguish it from airspace (and terrestrial locations). There is no discrete boundary between Earth's atmosphere and space, as the atmosphere gradually attenuates with increasing altitude. Outer space within the Solar System is called interplanetary space, which passes over into interstellar space at what is known as the heliopause.
Outer space is sparsely filled with several dozen types of organic molecules discovered to date by microwave spectroscopy, blackbody radiation left over from the Big Bang and the origin of the universe, and cosmic rays, which include ionized atomic nuclei and various subatomic particles. There is also some gas, plasma and dust, and small meteors. Additionally, there are signs of human life in outer space today, such as material left over from previous crewed and uncrewed launches which are a potential hazard to spacecraft. Some of this debris re-enters the atmosphere periodically.
Although Earth is the only body within the Solar System known to support life, evidence suggests that in the distant past the planet Mars possessed bodies of liquid water on the surface.[102] For a brief period in Mars' history, it may have also been capable of forming life. At present though, most of the water remaining on Mars is frozen. If life exists at all on Mars, it is most likely to be located underground where liquid water can still exist.[103]
Conditions on the other terrestrial planets, Mercury and Venus, appear to be too harsh to support life as we know it. But it has been conjectured that Europa, the fourth-largest moon of Jupiter, may possess a sub-surface ocean of liquid water and could potentially host life.[104]
Astronomers have started to discover extrasolar Earth analogs – planets that lie in the habitable zone of space surrounding a star, and therefore could possibly host life as we know it.[105]
See also
Media:
- National Wildlife, a publication of the National Wildlife Federation
- Natural History, by Pliny the Elder
- Natural World (TV series)
- Nature, by Ralph Waldo Emerson
- Nature, a prominent scientific journal
- Nature (TV series)
- The World We Live In (Life magazine)
Organizations:
Philosophy:
- Balance of nature (biological fallacy), a discredited concept of natural equilibrium in predator–prey dynamics
- Mother Nature
- Naturalism, any of several philosophical stances, typically those descended from materialism and pragmatism that do not distinguish the supernatural from nature;[106] this includes the methodological naturalism of natural science, which makes the methodological assumption that observable events in nature are explained only by natural causes, without assuming either the existence or non-existence of the supernatural
- Nature (philosophy)
Notes and references
- ^ "Definition of NATURE". Merriam-Webster. January 2, 2024. Archived from the original on January 2, 2024. Retrieved January 7, 2024.
- ^ a b c d Ducarme, Frédéric; Couvet, Denis (2020). "What does 'nature' mean?". Palgrave Communications. 6 (14). Springer Nature. doi:10.1057/s41599-020-0390-y.
- ^ Isaac Newton's Philosophiae Naturalis Principia Mathematica (1687), for example, is translated "Mathematical Principles of Natural Philosophy", and reflects the then-current use of the words "natural philosophy", akin to "systematic study of nature"
- ^ The etymology of the word "physical" shows its use as a synonym for "natural" in about the mid-15th century: Harper, Douglas. "physical". Online Etymology Dictionary. Retrieved September 20, 2006.
- ^ Harper, Douglas. "nature". Online Etymology Dictionary. Retrieved September 23, 2006.
- ^ An account of the pre-Socratic use of the concept of φύσις may be found in Naddaf, Gerard (2006) The Greek Concept of Nature, SUNY Press, and in Ducarme, Frédéric; Couvet, Denis (2020). "What does 'nature' mean?". Palgrave Communications. 6 (14). Springer Nature. doi:10.1057/s41599-020-0390-y.. The word φύσις, while first used in connection with a plant in Homer, occurs early in Greek philosophy, and in several senses. Generally, these senses match rather well the current senses in which the English word nature is used, as confirmed by Guthrie, W.K.C. Presocratic Tradition from Parmenides to Democritus (volume 2 of his History of Greek Philosophy), Cambridge UP, 1965.
- ^ The first known use of physis was by Homer in reference to the intrinsic qualities of a plant: ὣς ἄρα φωνήσας πόρε φάρμακον ἀργεϊφόντης ἐκ γαίης ἐρύσας, καί μοι φύσιν αὐτοῦ ἔδειξε. (So saying, Argeiphontes [=Hermes] gave me the herb, drawing it from the ground, and showed me its nature.) Odyssey 10.302–303 (ed. A.T. Murray). (The word is dealt with thoroughly in Liddell and Scott's Greek Lexicon Archived March 5, 2011, at the Wayback Machine.) For later but still very early Greek uses of the term, see earlier note.
- ^ "World Climates". Blue Planet Biomes. Archived from the original on December 17, 2008. Retrieved September 21, 2006.
- ^ "Calculations favor reducing atmosphere for early Earth". Science Daily. September 11, 2005. Archived from the original on August 30, 2006. Retrieved January 6, 2007.
- ^ "Past Climate Change". U.S. Environmental Protection Agency. October 19, 2006. Archived from the original on May 11, 2012. Retrieved January 7, 2007.
- ^ Hugh Anderson; Bernard Walter (March 28, 1997). "History of Climate Change". NASA. Archived from the original on January 23, 2008. Retrieved January 7, 2007.
- ^ Weart, Spencer (June 2006). "The Discovery of Global Warming". American Institute of Physics. Archived from the original on August 4, 2011. Retrieved January 7, 2007.
- ^ Dalrymple, G. Brent (1991). The Age of the Earth. Stanford: Stanford University Press. ISBN 978-0-8047-1569-0.
- ^ Morbidelli, A.; et al. (2000). "Source Regions and Time Scales for the Delivery of Water to Earth". Meteoritics & Planetary Science. 35 (6): 1309–1320. Bibcode:2000M&PS...35.1309M. doi:10.1111/j.1945-5100.2000.tb01518.x.
- ^ "Earth's Oldest Mineral Grains Suggest an Early Start for Life". NASA Astrobiology Institute. December 24, 2001. Archived from the original on September 28, 2006. Retrieved May 24, 2006.
- ^ a b Margulis, Lynn; Dorian Sagan (1995). What is Life?. New York: Simon & Schuster. ISBN 978-0-684-81326-4.
- ^ Murphy, J.B.; R.D. Nance (2004). "How do supercontinents assemble?". American Scientist. 92 (4): 324. doi:10.1511/2004.4.324. Archived from the original on January 28, 2011. Retrieved August 23, 2010.
- ^ Kirschvink, J.L. (1992). "Late Proterozoic Low-Latitude Global Glaciation: The Snowball Earth" (PDF). In J.W. Schopf; C. Klein (eds.). The Proterozoic Biosphere. Cambridge: Cambridge University Press. pp. 51–52. ISBN 978-0-521-36615-1. Archived (PDF) from the original on September 9, 2014. Retrieved September 22, 2006.
- ^ Raup, David M.; J. John Sepkoski Jr. (March 1982). "Mass extinctions in the marine fossil record". Science. 215 (4539): 1501–1503. Bibcode:1982Sci...215.1501R. doi:10.1126/science.215.4539.1501. PMID 17788674. S2CID 43002817.
- ^ Margulis, Lynn; Dorian Sagan (1995). What is Life?. New York: Simon & Schuster. p. 145. ISBN 978-0-684-81326-4.
- ^ Diamond J; Ashmole, N. P.; Purves, P. E. (1989). "The present, past and future of human-caused extinctions". Philos Trans R Soc Lond B Biol Sci. 325 (1228): 469–476, discussion 476–477. Bibcode:1989RSPTB.325..469D. doi:10.1098/rstb.1989.0100. PMID 2574887.
- ^ Novacek M; Cleland E (2001). "The current biodiversity extinction event: scenarios for mitigation and recovery". Proc Natl Acad Sci USA. 98 (10): 5466–5470. Bibcode:2001PNAS...98.5466N. doi:10.1073/pnas.091093698. PMC 33235. PMID 11344295.
- ^ Wick, Lucia; Möhl, Adrian (2006). "The mid-Holocene extinction of silver fir (Abies alba) in the Southern Alps: a consequence of forest fires? Palaeobotanical records and forest simulations" (PDF). Vegetation History and Archaeobotany. 15 (4): 435–444. Bibcode:2006VegHA..15..435W. doi:10.1007/s00334-006-0051-0. S2CID 52953180. Archived (PDF) from the original on November 15, 2018. Retrieved November 15, 2018.
- ^ The Holocene Extinction Archived September 25, 2006, at the Wayback Machine. Park.org. Retrieved on November 3, 2016.
- ^ Mass Extinctions Of The Phanerozoic Menu Archived September 25, 2006, at the Wayback Machine. Park.org. Retrieved on November 3, 2016.
- ^ Patterns of Extinction Archived September 25, 2006, at the Wayback Machine. Park.org. Retrieved on November 3, 2016.
- ^ Miller; Spoolman, Scott (September 28, 2007). Environmental Science: Problems, Connections and Solutions. Cengage Learning. ISBN 978-0-495-38337-6.
- ^ Stern, Harvey; Davidson, Noel (May 25, 2015). "Trends in the skill of weather prediction at lead times of 1–14 days". Quarterly Journal of the Royal Meteorological Society. 141 (692): 2726–2736. Bibcode:2015QJRMS.141.2726S. doi:10.1002/qj.2559. S2CID 119942734.
- ^ "Tropical Ocean Warming Drives Recent Northern Hemisphere Climate Change". Science Daily. April 6, 2001. Archived from the original on April 21, 2006. Retrieved May 24, 2006.
- ^ "Water for Life". Un.org. March 22, 2005. Archived from the original on May 14, 2011. Retrieved May 14, 2011.
- ^ "World". CIA – World Fact Book. Archived from the original on January 26, 2021. Retrieved December 20, 2008.
- ^ Water Vapor in the Climate System, Special Report, American Geophysical Union, December 1995.
- ^ Vital Water. UNEP.
- ^ "Ocean Archived January 26, 2011, at the Wayback Machine". The Columbia Encyclopedia. 2002. New York: Columbia University Press
- ^ "Distribution of land and water on the planet Archived May 31, 2008, at the Wayback Machine". UN Atlas of the Oceans Archived September 15, 2008, at the Wayback Machine
- ^ Spilhaus, Athelstan F (1942). "Maps of the whole world ocean". Geographical Review. 32 (3): 431–435. Bibcode:1942GeoRv..32..431S. doi:10.2307/210385. JSTOR 210385.
- ^
Britannica Online. "Lake (physical feature)". Archived from the original on June 11, 2008. Retrieved June 25, 2008.
[a Lake is] any relatively large body of slowly moving or standing water that occupies an inland basin of appreciable size. Definitions that precisely distinguish lakes, ponds, swamps, and even rivers and other bodies of nonoceanic water are not well established. It may be said, however, that rivers and streams are relatively fast moving; marshes and swamps contain relatively large quantities of grasses, trees, or shrubs; and ponds are relatively small in comparison to lakes. Geologically defined, lakes are temporary bodies of water.
- ^ "Lake Definition". Dictionary.com. Archived from the original on September 5, 2016. Retrieved September 6, 2016.
- ^ River {definition} Archived February 21, 2010, at the Wayback Machine from Merriam-Webster. Accessed February 2010.
- ^ USGS – U.S. Geological Survey – FAQs Archived July 1, 2015, at the Wayback Machine, No. 17 What is the difference between mountain, hill, and peak; lake and pond; or river and creek?
- ^ Adams, C.E. (1994). "The fish community of Loch Lomond, Scotland: its history and rapidly changing status". Hydrobiologia. 290 (1–3): 91–102. Bibcode:1994HyBio.290...91A. doi:10.1007/BF00008956. S2CID 6894397. Archived from the original on January 14, 2012. Retrieved January 5, 2007.
- ^ Pidwirny, Michael (2006). "Introduction to the Biosphere: Introduction to the Ecosystem Concept". Fundamentals of Physical Geography (2nd Edition). Archived from the original on July 18, 2011. Retrieved September 28, 2006.
- ^ Odum, EP (1971) Fundamentals of ecology, 3rd edition, Saunders New York
- ^ Pidwirny, Michael (2006). "Introduction to the Biosphere: Organization of Life". Fundamentals of Physical Geography (2nd edition). Archived from the original on August 13, 2011. Retrieved September 28, 2006.
- ^ Khan, Firdos Alam (2011). Biotechnology Fundamentals. CRC Press. ISBN 978-1-4398-2009-4.
- ^ Bailey, Robert G. (April 2004). "Identifying Ecoregion Boundaries" (PDF). Environmental Management. 34 (Supplement 1): S14 – S26. Bibcode:2004EnMan..34S..14B. doi:10.1007/s00267-003-0163-6. PMID 15883869. S2CID 31998098. Archived from the original (PDF) on October 1, 2009.
- ^ Botkin, Daniel B. (2000) No Man's Garden, Island Press, pp. 155–157, ISBN 1-55963-465-0.
- ^ "Definition of Life". California Academy of Sciences. 2006. Archived from the original on February 8, 2007. Retrieved January 7, 2007.
- ^ Neveu M, Kim HJ, Benner SA (April 2013). "The "strong" RNA world hypothesis: fifty years old". Astrobiology. 13 (4): 391–403. Bibcode:2013AsBio..13..391N. doi:10.1089/ast.2012.0868. PMID 23551238.
- ^ Cech TR (July 2012). "The RNA worlds in context". Cold Spring Harb Perspect Biol. 4 (7): a006742. doi:10.1101/cshperspect.a006742. PMC 3385955. PMID 21441585.
- ^ Bernstein H, Byerly HC, Hopf FA, Michod RE (September 1985). "Genetic damage, mutation, and the evolution of sex". Science. 229 (4719): 1277–81. Bibcode:1985Sci...229.1277B. doi:10.1126/science.3898363. PMID 3898363.
- ^ The figure "about one-half of one percent" takes into account the following (See, e.g., Leckie, Stephen (1999). "How Meat-centred Eating Patterns Affect Food Security and the Environment". For hunger-proof cities: sustainable urban food systems. Ottawa: International Development Research Centre. ISBN 978-0-88936-882-8. Archived from the original on November 13, 2010., which takes global average weight as 60 kg.), the total human biomass is the average weight multiplied by the current human population of approximately 6.5 billion (see, e.g., "World Population Information". U.S. Census Bureau. Retrieved September 28, 2006.[permanent dead link ]): Assuming 60–70 kg to be the average human mass (approximately 130–150 lb on the average), an approximation of total global human mass of between 390 billion (390×109) and 455 billion kg (between 845 billion and 975 billion lb, or about 423 million–488 million short tons). The total biomass of all kinds on earth is estimated to be in excess of 6.8 x 1013 kg (75 billion short tons). By these calculations, the portion of total biomass accounted for by humans would be very roughly 0.6%.
- ^ Sengbusch, Peter V. "The Flow of Energy in Ecosystems – Productivity, Food Chain, and Trophic Level". Botany online. University of Hamburg Department of Biology. Archived from the original on July 26, 2011. Retrieved September 23, 2006.
- ^ Pidwirny, Michael (2006). "Introduction to the Biosphere: Species Diversity and Biodiversity". Fundamentals of Physical Geography (2nd Edition). Archived from the original on July 18, 2011. Retrieved September 23, 2006.
- ^ "How Many Species are There?". Extinction Web Page Class Notes. Archived from the original on September 9, 2006. Retrieved September 23, 2006.
- ^ "Animal." World Book Encyclopedia. 16 vols. Chicago: World Book, 2003. This source gives an estimate of from 2 to 50 million.
- ^ "Just How Many Species Are There, Anyway?". Science Daily. May 2003. Archived from the original on February 11, 2007. Retrieved September 26, 2006.
- ^ Withers, Mark A.; et al. (1998). "Changing Patterns in the Number of Species in North American Floras". Land Use History of North America. Archived from the original on September 23, 2006. Retrieved September 26, 2006. Website based on the contents of the book: Sisk, T.D., ed. (1998). Perspectives on the land use history of North America: a context for understanding our changing environment (Revised September 1999 ed.). U.S. Geological Survey, Biological Resources Division. USGS/BRD/BSR-1998-0003.
- ^ "Tropical Scientists Find Fewer Species Than Expected". Science Daily. April 2002. Archived from the original on August 30, 2006. Retrieved September 27, 2006.
- ^ Bunker, Daniel E.; et al. (November 2005). "Species Loss and Aboveground Carbon Storage in a Tropical Forest". Science. 310 (5750): 1029–1031. Bibcode:2005Sci...310.1029B. CiteSeerX 10.1.1.465.7559. doi:10.1126/science.1117682. PMID 16239439. S2CID 42696030.
- ^ Wilcox, Bruce A. (2006). "Amphibian Decline: More Support for Biocomplexity as a Research Paradigm". EcoHealth. 3 (1): 1–2. doi:10.1007/s10393-005-0013-5. S2CID 23011961.
- ^ Clarke, Robin; Robert Lamb; Dilys Roe Ward, eds. (2002). "Decline and loss of species". Global environment outlook 3: past, present and future perspectives. London; Sterling, VA: Nairobi, Kenya: UNEP. ISBN 978-92-807-2087-7.
- ^ "Why the Amazon Rainforest is So Rich in Species: News". Earthobservatory.nasa.gov. December 5, 2005. Archived from the original on February 25, 2011. Retrieved May 14, 2011.
- ^ "Why The Amazon Rainforest Is So Rich in Species". Sciencedaily.com. December 5, 2005. Archived from the original on February 25, 2011. Retrieved May 14, 2011.
- ^ Schopf, J. William; Kudryavtsev, Anatoliy B.; Czaja, Andrew D.; Tripathi, Abhishek B. (2007). "Evidence of Archean life: Stromatolites and microfossils". Precambrian Research. 158 (3–4): 141–155. Bibcode:2007PreR..158..141S. doi:10.1016/j.precamres.2007.04.009.
- ^ Schopf, JW (2006). "Fossil evidence of Archaean life". Philos Trans R Soc Lond B Biol Sci. 361 (1470): 869–885. doi:10.1098/rstb.2006.1834. PMC 1578735. PMID 16754604.
- ^ Raven, Peter Hamilton; Johnson, George Brooks (2002). Biology. McGraw-Hill Education. p. 68. ISBN 978-0-07-112261-0. Retrieved July 7, 2013.
- ^ a b Line, M. (January 1, 2002). "The enigma of the origin of life and its timing". Microbiology. 148 (Pt 1): 21–27. doi:10.1099/00221287-148-1-21. PMID 11782495.
- ^ "Photosynthesis more ancient than thought, and most living things could do it". Phys.org. Archived from the original on January 20, 2019. Retrieved January 19, 2019.
- ^ Berkner, L. V.; L. C. Marshall (May 1965). "On the Origin and Rise of Oxygen Concentration in the Earth's Atmosphere". Journal of the Atmospheric Sciences. 22 (3): 225–261. Bibcode:1965JAtS...22..225B. doi:10.1175/1520-0469(1965)022<0225:OTOARO>2.0.CO;2.
- ^ Schopf J (1994). "Disparate rates, differing fates: tempo and mode of evolution changed from the Precambrian to the Phanerozoic". Proc Natl Acad Sci USA. 91 (15): 6735–42. Bibcode:1994PNAS...91.6735S. doi:10.1073/pnas.91.15.6735. PMC 44277. PMID 8041691.
- ^ Microorganism at the Encyclopædia Britannica
- ^ "Unicellular". BiologyOnline.com. Retrieved August 5, 2008.
- ^ Szewzyk U; Szewzyk R; Stenström T (1994). "Thermophilic, anaerobic bacteria isolated from a deep borehole in granite in Sweden". Proc Natl Acad Sci USA. 91 (5): 1810–1813. Bibcode:1994PNAS...91.1810S. doi:10.1073/pnas.91.5.1810. PMC 43253. PMID 11607462.
- ^ Wolska K (2003). "Horizontal DNA transfer between bacteria in the environment". Acta Microbiol Pol. 52 (3): 233–243. PMID 14743976.
- ^ Horneck G (1981). "Survival of microorganisms in space: a review". Adv Space Res. 1 (14): 39–48. doi:10.1016/0273-1177(81)90241-6. PMID 11541716.
- ^ Solomon, Eldra; Martin, Charles; Martin, Diana W.; Berg, Linda R. (2019). Biology. Cengage Learning. pp. 408, 420–422. ISBN 978-1305179899.
- ^ "flora". Merriam-Webster Online Dictionary. Merriam-Webster. Archived from the original on April 30, 2006. Retrieved September 27, 2006.
- ^ "Glossary". Status and Trends of the Nation's Biological Resources. Reston, VA: Department of the Interior, Geological Survey. 1998. SuDocs No. I 19.202:ST 1/V.1-2. Archived from the original on July 15, 2007.
- ^ Elhacham, Emily; Ben-Uri, Liad; et al. (2020). "Global human-made mass exceeds all living biomass". Nature. 588 (7838): 442–444. Bibcode:2020Natur.588..442E. doi:10.1038/s41586-020-3010-5. PMID 33299177. S2CID 228077506.
- ^ Carrington, Damian (April 15, 2021). "Just 3% of world's ecosystems remain intact, study suggests". The Guardian. Archived from the original on November 24, 2021. Retrieved April 16, 2021.
- ^ Plumptre, Andrew J.; Baisero, Daniele; et al. (2021). "Where Might We Find Ecologically Intact Communities?". Frontiers in Forests and Global Change. 4: 626635. Bibcode:2021FrFGC...4.6635P. doi:10.3389/ffgc.2021.626635. hdl:10261/242175.
- ^ Cafaro, Philip (2022). "Reducing Human Numbers and the Size of our Economies is Necessary to Avoid a Mass Extinction and Share Earth Justly with Other Species". Philosophia. 50 (5): 2263–2282. doi:10.1007/s11406-022-00497-w. S2CID 247433264.
- ^ "Feedback Loops in Global Climate Change Point to a Very Hot 21st Century". Science Daily. May 22, 2006. Archived from the original on December 8, 2006. Retrieved January 7, 2007.
- ^ Kolbert, Elizabeth (2014). The Sixth Extinction: An Unnatural History. New York City: Henry Holt and Company. ISBN 978-0805092998.
- ^ Stokstad, Erik (May 5, 2019). "Landmark analysis documents the alarming global decline of nature". Science. doi:10.1126/science.aax9287. S2CID 166478506.
- ^ Brauman, Kate A.; Garibaldi, Lucas A. (2020). "Global trends in nature's contributions to people". PNAS. 117 (51): 32799–32805. Bibcode:2020PNAS..11732799B. doi:10.1073/pnas.2010473117. PMC 7768808. PMID 33288690.
- ^ Bradshaw, Corey J. A.; Ehrlich, Paul R.; Beattie, Andrew; Ceballos, Gerardo; Crist, Eileen; Diamond, Joan; Dirzo, Rodolfo; Ehrlich, Anne H.; Harte, John; Harte, Mary Ellen; Pyke, Graham; Raven, Peter H.; Ripple, William J.; Saltré, Frédérik; Turnbull, Christine; Wackernagel, Mathis; Blumstein, Daniel T. (2021). "Underestimating the Challenges of Avoiding a Ghastly Future". Frontiers in Conservation Science. 1. doi:10.3389/fcosc.2020.615419.
- ^ UK Government Official Documents, February 2021, "The Economics of Biodiversity: The Dasgupta Review Headline Messages" Archived May 20, 2022, at the Wayback Machine p. 2
- ^ Carrington, Damian (February 2, 2021). "Economics of biodiversity review: what are the recommendations?". The Guardian. Archived from the original on May 24, 2022. Retrieved November 13, 2021.
- ^ "Natural Resources contribution to GDP". World Development Indicators (WDI). November 2014. Archived from the original on December 23, 2014.
- ^ "GDP – Composition by Sector". The World Factbook. Central Intelligence Agency. Archived from the original on May 22, 2014. Retrieved February 19, 2017.
- ^ "Plant Conservation Alliance – Medicinal Plant Working Groups Green Medicine". US National Park Services. Archived from the original on October 9, 2006. Retrieved September 23, 2006.
- ^ Oosthoek, Jan (1999). "Environmental History: Between Science & Philosophy". Environmental History Resources. Archived from the original on June 26, 2007. Retrieved December 1, 2006.
- ^ "On the Beauty of Nature". The Wilderness Society. Archived from the original on September 9, 2006. Retrieved September 29, 2006.
- ^ History of Conservation Archived July 8, 2006, at the Wayback Machine BC Spaces for Nature. Accessed: May 20, 2006.
- ^ Rothenberg, David (2011). Survival of the Beautiful: Art, Science and Evolution. Bloomsbury. ISBN 978-1-60819-216-8.
- ^ Feynman, Richard (1965). The Character of Physical Law. Modern Library. ISBN 978-0-679-60127-2.
- ^ Ade, P. A. R.; Aghanim, N.; Armitage-Caplan, C.; et al. (Planck Collaboration) (March 22, 2013). "Planck 2013 results. I. Overview of products and scientific results – Table 9". Astronomy and Astrophysics. 571: A1. arXiv:1303.5062. Bibcode:2014A&A...571A...1P. doi:10.1051/0004-6361/201321529. S2CID 218716838.
- ^ Taylor, Barry N. (1971). "Introduction to the constants for nonexperts". National Institute of Standards and Technology. Archived from the original on January 7, 2007. Retrieved January 7, 2007.
- ^ Varshalovich, D.A.; Potekhin, A.Y. & Ivanchik, A.V. (2000). "Testing cosmological variability of fundamental constants". AIP Conference Proceedings. 506: 503. arXiv:physics/0004062. Bibcode:2000AIPC..506..503V. CiteSeerX 10.1.1.43.6877. doi:10.1063/1.1302777.
- ^ Bibring, J; et al. (2006). "Global mineralogical and aqueous mars history derived from OMEGA/Mars Express data". Science. 312 (5772): 400–404. Bibcode:2006Sci...312..400B. doi:10.1126/science.1122659. PMID 16627738. S2CID 13968348.
- ^ Malik, Tariq (March 8, 2005). "Hunt for Mars life should go underground". Space.com via NBC News. Archived from the original on September 30, 2013. Retrieved September 4, 2006.
- ^ Turner, Scott (March 2, 1998). "Detailed Images From Europa Point To Slush Below Surface". NASA. Archived from the original on September 29, 2006. Retrieved September 28, 2006.
- ^ Choi, Charles Q. (March 21, 2011) New Estimate for Alien Earths: 2 Billion in Our Galaxy Alone | Alien Planets, Extraterrestrial Life & Extrasolar Planets | Exoplanets & Kepler Space Telescope Archived July 3, 2013, at the Wayback Machine. Space.com.
- ^ Papineau, David (2016) "Naturalism", The Stanford Encyclopedia of Philosophy, Edward N. Zalta (ed.), Archived April 1, 2019, at the Wayback Machine>
Further reading
- Droz, Layna; et al. (May 31, 2022). "Exploring the diversity of conceptualizations of nature in East and South-East Asia". Humanities and Social Sciences Communications. 9 (1): 1–12. doi:10.1057/s41599-022-01186-5. ISSN 2662-9992.
- Ducarme, Frédéric; Couvet, Denis (2020). "What does 'nature' mean?". Palgrave Communications. 6 (14). Springer Nature. doi:10.1057/s41599-020-0390-y.
- Emerson, Ralph W. (1836). Nature. Boston: James Munroe & Co.
- Farber, Paul Lawrence (2000), Finding Order in Nature: The Naturalist Tradition from Linnaeus to E. O. Wilson. Johns Hopkins University Press: Baltimore.
- Lynch, Derek (October 17, 2023). "Have we reached the end of nature? Our relationship with the environment is in crisis". The Conversation. Archived from the original on October 22, 2023.
- Naddaf, Gerard (2006). The Greek Concept of Nature. Albany: SUNY Press.
- Piccolo, John J.; Taylor, Bron; Washington, Haydn; Kopnina, Helen; Gray, Joe; Alberro, Heather; Orlikowska, Ewa (2022). ""Nature's contributions to people" and peoples' moral obligations to nature". Biological Conservation. 270: 109572. Bibcode:2022BCons.27009572P. doi:10.1016/j.biocon.2022.109572. S2CID 248769087.
- Worster, D. (1994). Nature's Economy: A History of Ecological Ideas. Cambridge: Cambridge University Press.
External links
- The IUCN Red List of Threatened Species (iucnredlist.org) Archived June 27, 2014, at the Wayback Machine
- Ducarme, Frédéric (January 3, 2021). "What is nature?". Encyclopedia of the Environment. Archived from the original on April 23, 2021.