Nature
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Galunggung in 1982, showing a combination of natural events. |
Nature, 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 spiritual or supernatural. It ranges in scale from the
subatomic to the
galactic.
The word "nature" derives from the Latin word
natura, or "the course of things, natural character."
[www.etymologyonline.com ([1])] Natura was a Latin translation of the Greek word
physis (φύσις), which originally related to the innate way in which plants and animals grow of their own accord, and to the Greek word for plants generally.
[ The first known use of physis is in Homer's Iliad, in reference to the intrinsic qualities of a plant. Later uses expanded to the "inherent" or "innate" character of things in general.] The concept of nature as a whole, the physical
universe, is a more recent development that gained increasingly wide use with 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]] |
View of the home planet, 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. |
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.
Main article: Earth.
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Phylum Pediastrumboryanum. Plankton have been part of nature on the Earth for at least the past 2 billion years.[Margulis, Lynn, & Sagan, Dorion. What is Life? (1995)] |
Earth (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 planets and the only place in the
universe currently known to support life.
The most prominent features of the earth's climate are its two large polar regions, two relatively narrow
temperate zones, and a wide
equatorial
tropical to
subtropical region.
[An excellent summary description of global climate can be found at [3] (www.blueplanetbiomes.org/climate.htm).] Precipitation patterns vary widely according to location, ranging from several meters of water per year to less than a millimeter. About 70% of the surface is covered in salt water oceans, and the remainder consists of continents and islands, with the vast majority of the habitable land in the
Northern Hemisphere. Ocean currents are important factors in determining climate, particularly the massive 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; without the redistributions of heat energy by the ocean currents as well as atmosphere, the tropics would be much hotter, the polar regions much colder.
Earth has evolved through geological and biological processes that have left traces of the original conditions. The
outer surface is divided into several
tectonic plates 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, 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 finely regulated, 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.
Based on the available evidence, scientists have been able to reconstruct detailed information about the planet's past. Earth is believed to have formed around 4.55 billion years ago out of the
solar nebula, along with the Sun and other planets.
[G.B. Dalrymple, 1991, "The Age of the Earth", Stanford University Press, California, ISBN 0-8047-1569-6.] 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
comets,
produced the oceans.
[A. Morbidelli et al, 2000, "Source Regions and Time Scales for the Delivery of Water to Earth", Meteoritics & Planetary Science, vol. 35, no. 6, pp. 1309-1320.] The highly energetic chemistry is believed to have produced a self-replicating molecule around 4 billion years ago.
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Land-based plants and fungi have been part of nature on Earth for about the past 400 million years. These have needed to adapt and move many times as the continents and climates changed.[http://www.greenspirit.org.uk/resources/chronology.htm][Stanley, Steven. Earth System History (1998)] |
Continents formed, then broke up and reformed as the surface of Earth reshaped itself over the course of hundreds of millions of years, occasionally combining to form 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.
[J.B. Murphy, R.D. Nance, "How do supercontinents assemble?", American Scentist, vol. 92, pp. 324-333.] There is significant evidence, still being discussed among scientists, that a severe
glacial action during the
Neoproterozoic era covered much of the planet in a sheet of ice. This hypothesis has been termed the "
Snowball Earth", and it is of particular interest as it precedes the
Cambrian explosion in which multi-cellular lifeforms began to widely proliferate the Earth about 530-540 million years ago.
[ J.L. Kirschvink, 1992, "Late Proterozoic Low-Latitude Global Glaciation: The Snowball Earth", The Proterozoic Biosphere, pp 51-52.]Since the
Cambrian explosion there have been five distinctly identifiable
mass extinctions.
[D. Raup & J. Sepkoski, 1982, "Mass extinctions in the marine fossil record", Science, vol. 215, pp. 1501"1503.] The last mass extinction occurred some 65 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, which then resembled shrews. Over the last 65 million years, mammalian life diversified.
[See, e.g., Margulis, Lynn, & Sagan, Dorion. What is Life? (1995) 145 ff.]Several million years ago, a species of small African ape gained the ability to stand upright.
[Margulis, Lynn & Sagan, Dorion. What is Life? (Weidenfeld and Nicolson, 1995)] The subsequent advent of human life, and the development of agriculture and further
civilization allowed humans to affect the Earth in a relatively short timespan like no other life form had before, affecting both the nature and quantity of other life forms as well as global climate.
Main article: Life.
Main article: Biosphere.
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.
[L. V. Berkner, L. C. Marshall, 1965, "On the Origin and Rise of Oxygen Concentration in the Earth's Atmosphere", Journal of the Atmospheric Sciences, Vol. 22, No. 3, pp. 225"261.] 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.
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. 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 x10
13 kg) of
biomass (life), which lives within various environments within the biosphere.
[Estimates which include the total amount of dead or inactive plant and animal matter, or "dry biomass", range to 1250 billion tons (about 1100 billion metric tonnes) or more. This does not include estimates of the amount of fossil fuels which were once biotic, but have been converted into their present form by extreme heat and pressure.] Over nine-tenths of the total biomass on Earth is plant life, on which animal life depends very heavily for its existence.
[Peter V. Sengbusch. "The Flow of Energy in Ecosystems - Productivity, Food Chain, and Trophic Level", University of Hamburg Department of Biology page at [4]] More than 2 million species of plant and animal life have been identified to date,
[Pidwirny, Michael, PhD: FUNDAMENTALS OF PHYSICAL GEOGRAPHY, 2006, CHAPTER 9: Introduction to the Biosphere, Species Deversity and Biodiversity [5]] and estimates of the actual number of existing species range from several million to well over 50 million.
[Wolosz, Thomas. How Many Species are There? Center for Earth & Environmental Sciences, SUNY at Plattsburgh, 1988.]["Animal." World Book Encyclopedia. 16 vols. Chicago: World Book, 2003. This source gives an estimate of from 2-50 million.][Just_How_Many_Species_Are_There,_Anyway? Society For Conservation Biology. 26 May 20.] 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.
[See, e.g., Withers, Mark A. et al: "Changing Patterns in the Number of Species in North American Floras" [6]]["Tropical Scientists Find Fewer Species Than Expected." Sciencedaily.com] The number of species presently is in rapid decline.
[Bunker, Daniel, DeClerck, Fabrice, et al. "Species Loss and Aboveground Carbon Storage in a Tropical Forest" Science 11 November 2005: Vol. 310. no. 5750, pp. 1029 - 1031 DOI: 10.1126/science.1117682 [7]][Wlicox, Bruce. "Amphibian Decline: More Support for Biocomplexity as a Research Paradigm" [8]][GEO: Global Environmental Outlook-3 "Decline and loss of species" (Klaus Töpfer, Ed., 2002) ISBN 9280720872 [9]]The distinction between plant and animal life is not sharply drawn, with some categories of life that stand between or across the two. Originally
Aristotle divided all living things between plants, which generally do not move, 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,
[[10]][[11]] and some classifications use the term
bacterial flora separately from
plant flora.
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A confluence of "natural" and a "made" environment. |
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 geography. Regional floras commonly are divided into categories such as
native flora and
agricultural and garden flora, the latter of which are intentionally grown and cultivated. 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, though not traced by scientists to having legs or wings instead of roots and leaves. Animals are
eukaryotic and usually
multicellular (although see
Myxozoa), 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
sponges (Phylum Porifera), animals have bodies differentiated into separate
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.
Although humans currently comprise less than one-tenth of one-percent of the total biomass on Earth, human impact 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 clearcut 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.
Main article: Ecology.
Main article: Ecosystem.
All forms of life are highly interactive with the environment in which they exist, and also with other life forms. In the 20th Century this premise gave rise to the concept of
ecosystems, which can be defined as any situation where there is interaction between organisms and their environment. Ecosystems are composed of a variety of
abiotic and
biotic components that function in an interrelated way.
[Pidwirny, Michael, PhD: FUNDAMENTALS OF PHYSICAL GEOGRAPHY, 2006, Ch. 9: Introduction to the Biosphere, sect. on "Introduction to the Ecosystem Concept" [12]] Some of the more important components are: soil, atmosphere, radiation from the sun, water, and living organisms. Each living organism has an ongoing and continual relationship with every other element that makes up its environment. 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. Michael Pidwirny, in
Fundamentals of Physical Geography, describes the concept as follows:
Ecosystems are dynamic entities composed of the biological community and the abiotic environment. An ecosystem's abiotic and biotic composition and structure is determined by the state of a number of interrelated environmental factors. Changes in any of these factors (for example: nutrient availability, temperature, light intensity, grazing intensity, and species population density) will result in dynamic changes to the nature of these systems. For example, a fire in the temperate deciduous forest completely changes the structure of that system. There are no longer any large trees, most of the mosses, herbs, and shrubs that occupy the forest floor are gone, and the nutrients that were stored in the biomass are quickly released into the soil, atmosphere and hydrologic system. After a short time of recovery, the community that was once large mature trees now becomes a community of grasses, herbaceous species, and tree seedlings.[Pidwirny, Michael, PhD: FUNDAMENTALS OF PHYSICAL GEOGRAPHY, 2006, Ch. 9: Introduction to the Biosphere, sect. "Organization of Life..." [13],]
Every species has limits of tolerance to factors that affect its survival, reproductive success and ability to continue to thrive and interact sustainably with the rest of its environment, which in turn may have effects on these factors for many other species or even on the whole of life.
[Pidwirny at Ch.9e, esp. section on "Abiotic Factors and Tolerance Limits." [14].] The concept of an ecosystem is thus an important subject of study, as such study provides information needed to make decisions about how human life may interact in a way that allows the various ecosystems to be sustained for future use rather than used up or otherwise rendered ineffective. For the purpose of such study, a unit of smaller size is called a
microecosystem. For example, an ecosystem can be a stone and all the life under it. A
macroecosystem might involve a whole
ecoregion, with its
drainage basin.
[Bailey, Robert C. "Identifying Ecoregion Boundaries", in Environmental Management 34: S14-S26, 2005. ([15]) Also published at U.S. Forest Service website ([16]).] The following ecosystems are examples of the kinds currently under intensive study:
* "continental ecosystems", such as "forest ecosystems", "meadow ecosystems" such as
steppes or
savannas), or
agro-ecosystems
* systems in inland waters, such as
lentic ecosystem"s such as
lakes or
ponds; or
lotic ecosystems such as
rivers
*
oceanic ecosystems.
Another classification can be done by reference to its communities, such as in the case of a
human ecosystem. 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, known as the
Gaia theory.
Main article: Wilderness.
Main article: Natural environment.
Wilderness is generally defined as a
natural environment on
Earth that has not been directly modified by
human activity.
Ecologists 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 twelve things to avoid in painting.
[Chinese brush painting Asia-art.net Accessed: May 20, 2006. ]The idea of wilderness having intrinsic value emerged in the
Western world in the 1800s.
British artists
John Constable and
JMW Turner turned their attention to capturing the beauty of the natural world in their paintings. Prior to 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. ] |
Salmon fry hatching. One of the original roots of the Latin word natura was natus, from nasci translated as "to be born".[Etymology of "nature" at www.etymologyonline.com ([17])] |
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
art,
photography,
poetry and other literature shows the strength with which many people associate nature and beauty. Why this association exists, and what the association consists of, is studied by the branch of philosophy called
aesthetics. Beyond certain basic characteristics agreed by many philosophers to explain what is seen as beautiful, the opinions are virtually endless.
[For an example of a range of opinions, see [18] and Ralph Waldo Emerson's analysis of the subject at [19]]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 that strikes the senses, the beauty of quality and appearances; 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." [Quoted in, Flake, Gary William: The Computational Beauty of Nature, 1998.]
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.
Main article: Matter.
Main article: 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 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).
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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. |
Main article: Outer space.
Main article: 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.
Although outer space is certainly spacious, it is far from empty. Outer space is sparsely filled with several dozen
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 space craft. Some of this
debris re-enters the atmosphere periodically.
*
Biophilia*
Mother Nature*
Naturefriends*
Natural environment*
Natural units (Planck units)
*
Materialism*
Next nature*
Naturalism (philosophy): any of several philosophical stances, typically those descended from
Materialism and
Pragmatism that do not distinguish the
supernatural from nature. 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.
*
Metaphysical naturalism, any
worldview in which nature is all there is and nothing
supernatural exists.
*
Wilderness*
Philosophy of nature*
Natural Philosophy*
Natural science*
The Essence of Nature Magazine - An online magazine dedicated to nature, animals, and the environment.
*
The Nature Conservancy - a charitable organization devoted to preserving natural diversity worldwide
*
English Nature UK government organization devoted to preserving natural diversity in the UK
*
Nature Detectives An online research and education project for under 18s in the UK
*
A Guide to Nature and Wildlife Conservation*
Nature Picture*
Nature (1869-1875) This collection of Nature provides insight into the developments and achievements of science at the end of the nineteenth century.
