in 1982, showing a combination of natural events.]]
, Victoria , Australia . Much attention has been given to preserving the Flora and other natural characteristics of the view, while allowing ample access for visitors to this popular site.]]
, in the broadest sense, is equivalent to the '''natural world''', '''physical universe''', '''material world''' or '''material universe'''. "Nature" refers to the Phenomena of the physical world, and also to Life in general. The term generally does not include manufactured objects and human interaction unless qualified in ways such as, e.g., " Human Nature " or "the whole of nature". Nature is also 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 "the course of things, natural character."1 ''Natura'' was a Latin translation of the Greek word '', 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.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: 2
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 or human-like Consciousness or Mind .
, taken in 1972 by the Apollo 17 crew. This image is the only photograph of its kind to date, showing a fully sunlit hemisphere of the Earth.]]
See Also: Earth
Earth science
structure of the Earth
plate tectonics
geology
(or, "the earth") is the fifth largest Planet in the Solar System , third in order of distance from the Sun . It is the largest of its Planetary System 's Terrestrial Planet s and the only place in the Universe known to support life.
The most prominent features of the earth's climate are its two large polar regions, two relatively narrow patterns vary widely according to location, ranging from several Metre s of water per year to less than a Millimetre . About 70 percent of the surface is covered by salt-water oceans. The remainder consists of continents and islands, with the vast majority 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 Tectonic Plate s that gradually migrate across the surface over geologic time spans, which at least several times have changed relatively quickly. The interior of the planet remains active, with a thick layer of molten Earth Mantle and an iron-filled core that generates a Magnetic Field .
The Atmospheric conditions have been significantly altered from the original conditions by the presence of life forms,4 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,5 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.67
See Also: History of Earth
Based on the available evidence, scientists have reconstructed detailed information about the planet's past. Earth is estimated to have formed approximately 4.55 billion years ago out of the Solar Nebula , along with the Sun and other planets.9 The moon formed relatively soon afterwards (roughly 20 million years later, or 4.53 billion years ago).
Initially molten, the outer layer of the planet cooled, resulting in the solid crust. Outgassing and Volcanic activity produced the primordial atmosphere. Condensing Water Vapor , augmented by Ice delivered by Comet s, Produced The Oceans .10 The highly energetic chemistry is believed to have produced a self-replicating molecule around 4 billion years ago.11
|
Several million years ago, a species of small African ape gained the ability to stand upright.
18 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
Oxygen Catastrophe , 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.
1920 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."The mid-Holocene extinction of silver fir (Abies alba) in the ..."
pdf The extent of the current extinction event is still being researched, debated and calculated by biologists.See, e.g.
[http://park.org/Canada/Museum/extinction/extincmenu.html , [http://park.org/Canada/Museum/extinction/patterns.html]
See Also: Earth's atmosphere
weather
climate
The atmosphere of the Earth serves as a key factor in sustaining the planetary '' (a mathematical constant
forming a
Thunderstorm with an associated
Strong Updraft and a heavy precipitation of
Hail .]]
Terrestrial weather occurs almost exclusively in the
Lower Part Of The Atmosphere , and serves as a convective system for redistributing heat. 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
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 dependent on its growth for their food.
The planetary 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 Gas es, variations in the solar luminosity, and changes to the planet's orbit. Based on historical records, the Earth is known to have undergone drastic climate changes in the past, including
Ice Age s.
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 planet 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 currently limited to only a few days. Overall, two things are currently happening worldwide: (1) temperature is increasing on the average; and (2) regional climates have been undergoing noticeable changes.
23
See Also: Life
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 .
24 Life may also be said to be simply the characteristic state of
Organism s.
is essential for continuing life]]
Properties common to terrestrial organisms (
Plant s,
Animal s,
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
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 10
13 Kilogram s) of
Biomass (life), which lives within various environments within the biosphere.The figure "about one-half of one percent" takes into account the following (See, e.g.,
25, 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.'',
26): Assuming 60-70kg to be the average human mass (approximately 130-150 lbs weight on the average), an approximation of total global human mass of between 390 billion and 455 billion kg (between 845 and 975 billion lb., or about 423-488 million tons). The total biomass of all kinds on earth is estimated to be in excess of 6.8 x 10
13 kg (75 billion tons). By these calculations, the portion of total biomass accounted for by humans would be very roughly 0.6%.
The following ecosystems are examples of the kinds currently under intensive study:
Another classification can be made by reference to its communities, such as in the case of a
Human Ecosystem . Regional groupings of distinctive plant and animals best adapted to the region's physical
Natural Environment , latitude, altitude, and terrain are known as
Biome s. The broadest classification, today under wide study and analysis, and also subject to widespread arguments about its nature and validity, is that of the entire sum of life seen as analogous to a self-sustaining organism; a theory studied as
Earth System Science (less formally known as
Gaia Theory ).
5051
in
Hawaii are the residence of
Tribes that make only small changes in the natural beauty surrounding them.]]
Although humans currently comprise only about one-half of one percent of the total living biomass on Earth, For an example of a range of opinions, see:
52 and
Ralph Waldo Emerson 's analysis of the subject:
53 the human effect on nature is disproportionately large. Because of the extent of human influence, the boundaries between what we 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 presently diminishing at an increasingly rapid pace, or, according to some, has already disappeared.
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.
54 Manmade 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.
Humans employ nature for both leisure and economic activities. The acquisition of natural resources for industrial use remains a primary component of the world's economic system. 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,
55 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.
56
, a wilderness area in
Queensland ,
Australia .]]
See Also: Wilderness
Natural environment
is generally defined as a
Natural Environment on
Earth that has not been directly modified by
Human activity.
Ecologist s consider wilderness areas to be an integral part of the planet's self-sustaining natural
Ecosystem (the
Biosphere ).
The word, "wilderness", derives from the notion of
Wildness ; in other words that which is not controllable by humans. The word's
Etymology is from the
Old English ''wildeornes'', which in turn derives from ''wildeor'' meaning ''wild
Beast '' (wild + deor = beast, deer)."Wilderness", in ''The Collins English Dictionary'' (2000) From this point of view, it is the wildness of a place that makes it a wilderness. The mere presence or activity of people does not disqualify an area from being "wilderness." Many ecosystems that are, or have been, inhabited or influenced by activities of people may still be considered "wild." This way of looking at wilderness includes areas within which natural processes operate without very noticeable human interference.
Looked at through the lens of the
Visual Arts , nature and wildness have been important subjects in various epochs of world history. An early tradition of
Landscape Art occurred in 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. Artists learned to depict mountains and rivers "from the perspective of nature as a whole and on the basis of their understanding of the laws of nature … as if seen through the eyes of a bird." In the 13th century,
Shih Erh Chi listed "scenes lacking any places made inaccessible by nature," as one of the 12 things to avoid in painting.
Chinese brush painting Asia-art.net Accessed: May 20, 2006.
In the
Western World the idea of wilderness having intrinsic value emerged in the 1800s, especially in the works of the
Romantic Movement .
British artists
John Constable and
JMW 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.
History of Conservation BC Spaces for Nature. Accessed: May 20, 2006.
Fry hatching. The root of the
Latin "''natura''" {"nature") is "''natus''," from "''nasci''" ("to be born").
57]]
Beauty in nature is a common theme in modern life and in art, and books emphasizing beauty in nature fill large sections of libraries and bookstores. That nature has been depicted and celebrated by so much 's analysis of the subject:
59
Many scientists, who study nature in more specific and organized ways, also share the conviction that nature is beautiful; the French mathematician,
Jules Henri Poincaré (1854-1912) said:
The scientist does not study nature because it is useful; he studies it because he delights in it, and he delights in it because it is beautiful.If nature were not beautiful, it would not be worth knowing, and if nature were not worth knowing, life would not be worth living. Of course I do not here speak of that beauty which strikes the senses, the beauty of qualities and of appearance; not that I undervalue such beauty, far from it, but it has nothing to do with science; I mean that profounder beauty which comes from the harmonious order of the parts and which a pure intelligence can grasp.60
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 symmetry, equal division, and other perfect mathematical
Forms and notions.
Electron Orbital s shown as cross-sections with color-coded probability density]]
See Also: Matter
Energy
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.
Matter is commonly defined as the substance of which physical objects are composed. It constitutes the
Observable Universe . According to the theory of
Special Relativity , there is no unchangeable distinction between matter and
Energy , because matter can be converted to energy (see
Annihilation ), and vice versa (see
Matter Creation ). The visible components of the universe are now believed to compose only 4 percent of the total mass. The remainder is believed to consist of 23 percent cold
Dark Matter and 73 percent
Dark Energy .
61 The exact nature of these components is still unknown and is currently under intensive investigation by physicists.
See Also: Chemistry
Physics
See Also: Outer space
Universe
''', 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
, 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 Space at what is known as the
Heliopause .
64
Although outer space is certainly spacious, it is far from empty. Outer space is sparsely filled with several dozen types of
Organic Molecule s discovered to date by
Microwave Spectroscopy ,
Blackbody Radiation left over from the
Big Bang and the origin of the universe, and
Cosmic Ray s, which include
Ion ized
Atomic Nuclei and various
Subatomic Particle s. There is also some gas,
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
Debris re-enters the atmosphere periodically.
The planet Earth is currently the only known body within the solar system to support life. However, current evidence suggests that in the distant past the planet
Mars possessed bodies of liquid water on the surface.
65 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.
66
Conditions on the other terrestrial planets,
Mercury and
Venus , appears 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.
67
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 lay in the
Habitable Zone of space surrounding the
Star , and therefore could possibly host
Life as we know it.
See Also: Extraterrestrial life
