Nature

Lightning strikes during the eruption of the Galunggung volcano in 1982
Much attention has been given to preserving the natural characteristics of Hopetoun Falls, Australia, while allowing ample access for visitors.
Bachalpsee in the Swiss Alps; generally mountainous areas are less affected by human activity.
Cows grazing in a jungle

Nature, in the broadest sense, is equivalent to the natural world, physical world, material world. "Nature" refers to the phenomena of the physical world, and also to life in general. Manufactured objects and human interaction generally are not considered part of nature unless qualified in ways such as "human nature" or "the whole of nature". Nature is generally distinguished from the supernatural. It ranges in scale from the subatomic to the galactic.

The word nature is derived from the Latin word natura, or "essential qualities, innate disposition," but literally meaning "birth." Original sense is in "human nature." [1] Natura was a 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.[2] This is shown in the first written use of the word φύσις, in connection with a plant.[3] The concept of nature as a whole, the physical universe, is one of several expansions of the original notion; it began with certain core applications of the word φύσις by pre-Socratic philosophers, and has steadily gained currency ever since. This usage was confirmed during the advent of modern scientific method in the last several centuries.[4][5]

Within the various uses of the word today, "nature" may refer to the general realm of various types 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, and the matter and energy of which all these things are composed. It is often taken to mean the "natural environment" or wilderness–wild animals, rocks, forest, beaches, and in general those things that have not been substantially altered by human intervention, or which persist despite human intervention. This more traditional concept of natural things which can still be found today implies a distinction between the natural and the artificial, with the latter being understood as that which has been brought into being by a human consciousness or a human mind.

Etymology

Newton's Principia Mathematica (1687) used "nature" as a synonym for the physical universe.
See also Nature (philosophy)

The word nature means the universe, with all its phenomena.[6] Natura was a 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.[7] The word φύσις occurs very early in Greek philosophy, generally in similar senses to those of the modern English word nature.[8] This is shown in the first written use of the word φύσις, in connection with a plant by Homer.[9] The concept of nature as a whole, the physical universe, is one of several expansions of the original notion. This usage was confirmed during the advent of modern scientific method. Isaac Newton's Philosophiae Naturalis Principia Mathematica (1687), for example, is translated "Mathematical Principles of Natural Philosophy". The etymology of the word "physical" shows its use as a synonym for "natural" in about the mid-15th century.[10]

Life

Female mallard and ducklings - reproduction is essential for continuing life
Main articles: Life and Biosphere

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.[34] Life may also be said to be simply the characteristic state of organisms.

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 air, land, surface rocks and water – 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). Currently the entire Earth contains over 75 billion tons (150 trillion pounds or about 6.8 x 1013 kilograms) of biomass (life), which lives within various environments within the biosphere.[35]

Over nine-tenths of the total biomass on Earth is plant life, on which animal life depends very heavily for its existence.[36] More than 2 million species of plant and animal life have been identified to date,[37] and estimates of the actual number of existing species range from several million to well over 50 million.[38][39][40] 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.[41][42] The total number of species is presently in rapid decline.[43][44][45]

Evolution

Main article: Evolution

Life, as it is currently understood, is only known to exist on the planet Earth. The origin of life is still a poorly understood process, but it is thought to have occurred about 3.9 to 3.5 billion years ago during the hadean or archean eons on a primordial earth that had a substantially different environment than is found at present.[46] 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 formation 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.[46]

The advent of photosynthesis in very basic forms of plant life worldwide allowed the sun's energy to be harvested to create conditions allowing for more complex life. 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.[47] 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.

Nature beyond Earth

NGC 4414, a typical spiral galaxy in the constellation Coma Berenices, is about 56,000 light years in diameter and approximately 60 million light years distant.
The deepest visible-light image of the universe, the Hubble Ultra Deep Field, contains an estimated 10,000 galaxies in a patch of sky just one-tenth the diameter of the full moon. Image Credit: NASA, ESA, S. Beckwith (STScI) and the HUDF team.
Main articles: Outer space and Universe

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 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 space at what is known as the heliopause.

Outer space is certainly spacious, but it is far from empty. 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 manned and unmanned launches which are a potential hazard to spacecraft. Some of this debris re-enters the atmosphere periodically.

Although the planet Earth is currently the only known body within the solar system to support life, current evidence suggests that in the distant past the planet Mars possessed bodies of liquid water on the surface.[75] 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.[76]

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.[77]

Recently, the team of Stéphane Udry have discovered a new planet named Gliese 581 c, which is an extrasolar planet orbiting the red dwarf star Gliese 581. Gliese 581 c appears to lie in the habitable zone of space surrounding the

 star, and therefore could possibly host life as we know it.

See also: Extraterrestrial life

See also

Science:

Philosophy:

Media:

Organizations:

Notes and references

  1. Harper, Douglas. "Nature". Online Etymology Dictionary. http://www.etymonline.com/index.php?term=nature. Retrieved on September 23 2006. 
  2. A useful though somewhat erratically presented account of the pre-Socratic use of the concept of φύσις may be found in Naddaf, Gerard The Greek Concept of Nature, SUNY Press, 2006. 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.
  3. 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 10.302-3 (ed. A.T. Murray). (The word is dealt with thoroughly in Liddell and Scott's Greek Lexicon.) For later but still very early Greek uses of the term, see earlier note.
  4. 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"
  5. 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. http://www.etymonline.com/index.php?term=physical. Retrieved on September 20 2006. 
  6. Harper, Douglas (Sep 1985), "Nature", British journal of anaesthesia 57 (9): 866–71, doi:10.1093/bja/57.9.866, PMID 3161528, http://www.etymonline.com/index.php?term=nature, retrieved on 2006-09-23 
  7. Naddaf, Gerard (2006-02-09), The Greek Concept of Nature (New ed.), New York: State University of New York Press, ISBN 0791463745 
  8. Guthrie, W.K.C. (1965-01-02), Presocratic Tradition from Parmenides to Democritus, History of Greek Philosophy, 2, Cambridge: Cambridge University Press, ISBN 0521051606 
  9. Homer (1995-02-20). "10.302-3". in A.T. Murray (in Homeric Greek). Odyssey (2nd rev ed.). LOEB. ISBN 0674995619. "ὣς ἄρα φωνήσας πόρε φάρμακον ἀργεϊφόντης ἐκ γαίης ἐρύσας, καί μοι φύσιν αὐτοῦ ἔδειξε. (Argeiphontes [=Hermes] gave me the herb, drawing it from the ground, and showed me its nature.)" 
  10. Harper, Douglas, Physical, http://www.etymonline.com/index.php?term=physical, retrieved on 2006-09-20 
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