Difference between revisions of "Botany" - New World Encyclopedia

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[[Image:504px-Pinguiculagrandiflora1web.jpg|thumb|250px|Pinguicula grandiflora]]
 
[[Image:504px-Pinguiculagrandiflora1web.jpg|thumb|250px|Pinguicula grandiflora]]
'''Botany''' is the branch of [[biology]] dealing with the scientific study of [[plant]] life. It is also sometimes referred to as '''plant science(s)''' or '''plant biology'''. Botany covers a wide range of scientific disciplines that study the structure, growth, reproduction, [[metabolism]], development, diseases, [[ecology]], and [[evolution]] of [[plant]]s.
+
'''Botany''' is the branch of [[biology]] dealing with the scientific study of [[plant]] life. It is also sometimes referred to as '''plant science(s)''' or '''plant biology'''. Botany covers a wide range of scientific disciplines that study the structure, growth, reproduction, [[metabolism]], development, diseases, [[ecology]], and [[evolution]] of plants.  
 
 
Over 400,000 [[species]] of [[plant]]s have been documented on [[Earth]], playing a critical role in the [[food chain|food web]], [[biogeochemical cycle]]s, and maintaining ecological balance on [[Earth]]. Dating back to the Roman Empire, botany is one of the oldest disciplines of [[biology]].
 
  
 +
Over 400,000 [[species]] of plants have been documented on [[Earth]], playing a critical role in the [[food chain|food web]], [[biogeochemical cycle]]s, and maintaining ecological balance. Dating back to the Roman Empire, botany is one of the oldest disciplines of biology.
  
 
==History==
 
==History==
  
 
[[Image:Botany.jpg|thumb|right|The traditional tools of a botanist.]]
 
[[Image:Botany.jpg|thumb|right|The traditional tools of a botanist.]]
Among the earliest of botanical works, written around 300 B.C.E., are two large treatises by [[Theophrastus]], a philospher and disciple of Aristotle: ''On the History of Plants'' (''Historia Plantarum'') and ''On the Causes of Plants''. Together these books constitute the most important contribution to botanical science during antiquity and on into the Middle Ages. As a result, [[Theophrastus]] is considered the founder of botany. The Roman medical writer Dioscorides in the first century C.E., provided important evidence on Greek and Roman knowledge of medicinal [[plant]]s. He categorized plants based on their medicinal, culinary, or aromatic value.
+
Among the earliest of botanical works, written around 300 B.C.E., are two large treatises by [[Theophrastus]], a philosopher and disciple of [[Aristotle]]: ''On the History of Plants'' (''Historia Plantarum'') and ''On the Causes of Plants''. Together these books constitute the most important contribution to botanical science during antiquity and on into the Middle Ages. As a result, Theophrastus is considered the founder of botany.  
 
 
In 1665, using an early microscope, Robert Hooke discovered [[cell (biology)|cells]] in cork, a short time later in living [[plant]] tissue. The German Leonhart Fuchs, the Swiss Conrad von Gesner, and the British authors Nicholas Culpeper and John Gerard published herbals that gave information on the medicinal uses of plants. In 1753 Carl Linnaeus published ''Species Plantarum,'' which included 6,000 plant species. He established '''binomial nomenclature''', which has been used in the naming of living things ever since.
 
 
 
==Subdisciplines of Botany==
 
  
===Form and Function===
+
The Roman medical writer Dioscorides in the first century A.D., provided important evidence on Greek and Roman knowledge of medicinal [[plant]]s. He categorized plants based on their medicinal, culinary, or aromatic value.  
Seven key subdisciplines involve the study of different aspects of plants. These disciplines are [[gene|genetics]], cytology, [[anatomy]], morphology, physiology, pathology, and [[ecology]].
 
  
 +
In 1665, using an early microscope, Robert Hooke discovered [[cell (biology)|cells]] in cork and a short time later in living plant tissue. The German Leonhart Fuchs, the Swiss Conrad von Gesner, and the British authors Nicholas Culpeper and John Gerard published information on the medicinal uses of plants.
  
Genetics is the study of heredity, [[gene]]s, and [[gene]] function. Much modern botany has put to use plant [[DNA|deoxyribonucleic acid ([[DNA]])]] and genomic information to study [[plant]]s more rigorously. Molecular [[biology]] has allowed for [[taxonomy|taxonomist]]s to categorize [[plant]] [[species]] based on [[DNA]], which has allowed for certain classification. Plants have been classified into different families and renamed as a result. For this reason, older botanical guides may contain outdated names and classifications. A considerable amount of new knowledge today is being generated from studying model plants like ''Arabidopsis thaliana'' (mustard weed). This mustard weed was one of the first plants to have its genome sequenced. The sequencing of the rice genome and a large international research community have made rice the de facto cereal/grass/monocot model. Another grass [[species]], Brachypodium distachyon is also emerging as an experimental model for understanding the genetic, cellular and molecular biology of temperate grasses. Other commercially important staple foods like wheat, maize, barley, rye, millet and soybean are also having their genomes sequenced. Some of these are challenging to sequence because they have more than two haploid (n) sets of [[chromosome]]s, a condition known as polyploidy, common in the plant kingdom. The "Green Yeast" ''Chlamydomonas reinhardtii'' (a single-celled, green [[alga]]) is another [[plant]] model organism that has been extensively studied and provided important insights into cell biology.
+
In 1753, [[Carl Linnaeus]] published ''Species Plantarum,'' which included 6,000 plant species. He established the '''binomial nomenclature''', which has been used in the naming of living things ever since.
  
 +
==Subdisciplines of botany==
  
'''Systematics''' is the study of the diversity of organism characteristics, and especially how they relate [[evolution]]arily, establishing their phylogeny.  
+
===Form and function===
 +
Eight key subdisciplines involve the study of different aspects of plants. These disciplines are [[gene|genetics]], systematics, cytology, [[anatomy]], morphology, [[physiology]], pathology, and [[ecology]].
  
The term "systematics" may or may not overlap with "[[taxonomy|taxonomy]]" which concerns itself with scientific classification of [[species]] and other [[taxonomy|taxa]]. Recent developments are [[cladistics]] and molecular systematics.
+
'''Genetics''' is the study of heredity, [[gene]]s, and gene function. Much modern botany has put to use plant [[DNA|deoxyribonucleic acid ([[DNA]])]] and genomic information to study plants more rigorously. Molecular [[biology]] has allowed for [[taxonomy|taxonomist]]s to categorize plant species based on DNA. Plants have been classified into different families and renamed as a result. For this reason, older botanical guides may contain outdated names and classifications. A considerable amount of new knowledge today is being generated from studying model plants like ''Arabidopsis thaliana'' (mustard weed). Mustard weed was one of the first plants to have its genome sequenced. The sequencing of the [[rice]] genome and a large international research community have made rice the de facto cereal/grass/monocot model. Another [[grass]] species, ''Brachypodium distachyon'' is also emerging as an experimental model for understanding the genetic, cellular and molecular biology of temperate grasses. Other commercially important staple foods like [[wheat]], [[maize]], barley, rye, millet and soybean are also having their genomes sequenced. Some of these are challenging to sequence because they have more than two haploid (n) sets of [[chromosome]]s, a condition known as polyploidy, common in the plant kingdom. The "Green Yeast" ''Chlamydomonas reinhardtii'' (a single-celled, green [[algae]]) is another plant model organism that has been extensively studied and provided important insights into cell biology.
  
'''Cytology''' is the study of cells, including their function, structure, and life history.  
+
'''Systematics''' is the study of the diversity of organism characteristics, and especially how they relate [[evolution]]arily, establishing their phylogeny. The term "systematics" may or may not overlap with "[[taxonomy|taxonomy]]", which concerns itself with scientific classification of [[species]] and other [[taxonomy|taxa]]. Recent developments are [[cladistics]] and molecular systematics.
  
'''[[Anatomy]]''' is the study of the interior structure of living things.  
+
'''Cytology''' is the study of [[Cell (biology)|cells]], including their function, structure, and life history.  
  
'''Morphology''' is the study of the exterior form of plants, including the placement stems and leaves on a stem (i.e. alternate or opposite), and also the study of life histories and evolutionary development . Botanical field guides often rely on [[plant]] morphology to help biologists identify plant species in the field.  
+
'''Anatomy''' is the study of the interior structure of living things.  
  
'''Plant physiology''' is the study of the function of plants and their [[cell]]s and tissues. Examples of physiological research includes the study of [[photosynthesis|photosynthetic]] pathways in different [[plant]]s and mineral uptake by plants.
+
'''Morphology''' is the study of the exterior form of plants, including the placement stems and leaves on a stem (i.e. alternate or opposite), and also the study of life histories and evolutionary development. Botanical field guides often rely on plant morphology to help biologists identify plant species in the field.  
  
 +
'''Plant physiology''' is the study of the function of plants and their cells and tissues. Examples of physiological research includes the study of [[photosynthesis|photosynthetic]] pathways in different plants and mineral uptake by plants.
  
 
'''Pathology''' is the study of [[disease]]s and the structural and funcional changes that occur with diseases. This can be important for range of fields, including conservation biology, [[ecology]], agriculture, and horticulture.  
 
'''Pathology''' is the study of [[disease]]s and the structural and funcional changes that occur with diseases. This can be important for range of fields, including conservation biology, [[ecology]], agriculture, and horticulture.  
  
'''Ecology''' is the study of interactions between organisms living and their environment as an integrated system (Chapin et al. 2002).
+
'''Ecology''' is the study of interactions between organisms and their biotic and abiotic environment as an integrated system (Chapin et al. 2002).
  
 
===Other subdisciplines===
 
===Other subdisciplines===
Other subdisciplines of botany include ethnobotany, the study of how a particular culture or region has made use of local and indigenous plants, including their use for food, shelter, medicine, clothing, hunting and religion. While ethnobotany has its roots in botany, ethnobotanists also receive training in anthropology, sociology, history, religion, or mythology.  
+
Other subdisciplines of botany include '''ethnobotany''', the study of how a particular culture, or region has made use of local and indigenous plants, including their use for food, shelter, medicine, clothing, hunting and [[religion]]. While ethnobotany has its roots in botany, ethnobotanists also receive training in [[anthropology]], [[sociology]], [[history]], religion, or [[mythology]].  
  
[[Paleobotany]] is the study of fossil plants. '''Palynology''', the study of modern and fossil pollen, is also often grouped with paleobotany. Paleobotany and palynology are both instrumental in studying [[paleoclimatology]].   
+
'''Paleobotany''' is the study of [[fossil]] plants. '''Palynology''', the study of modern and fossil pollen, is also often grouped with paleobotany. [[Paleobotany]] and palynology are both instrumental in studying [[paleoclimatology]].   
  
Bryology is the study of mosses, liverworts, and hornworts; phycology is the study of [[algae]]; pteridolgy is the study of [[fern]]s; and mycology is the study of [[fungus|fungi]].
+
'''Bryology''' is the study of mosses, liverworts, and hornworts; '''phycology''' is the study of [[algae]]; '''pteridolgy''' is the study of [[fern]]s; and '''mycology''' is the study of [[fungus|fungi]].
  
 
==Scope and importance of botany==
 
==Scope and importance of botany==

Revision as of 02:33, 6 August 2006


Pinguicula grandiflora

Botany is the branch of biology dealing with the scientific study of plant life. It is also sometimes referred to as plant science(s) or plant biology. Botany covers a wide range of scientific disciplines that study the structure, growth, reproduction, metabolism, development, diseases, ecology, and evolution of plants.

Over 400,000 species of plants have been documented on Earth, playing a critical role in the food web, biogeochemical cycles, and maintaining ecological balance. Dating back to the Roman Empire, botany is one of the oldest disciplines of biology.

History

The traditional tools of a botanist.

Among the earliest of botanical works, written around 300 B.C.E., are two large treatises by Theophrastus, a philosopher and disciple of Aristotle: On the History of Plants (Historia Plantarum) and On the Causes of Plants. Together these books constitute the most important contribution to botanical science during antiquity and on into the Middle Ages. As a result, Theophrastus is considered the founder of botany.

The Roman medical writer Dioscorides in the first century C.E., provided important evidence on Greek and Roman knowledge of medicinal plants. He categorized plants based on their medicinal, culinary, or aromatic value.

In 1665, using an early microscope, Robert Hooke discovered cells in cork and a short time later in living plant tissue. The German Leonhart Fuchs, the Swiss Conrad von Gesner, and the British authors Nicholas Culpeper and John Gerard published information on the medicinal uses of plants.

In 1753, Carl Linnaeus published Species Plantarum, which included 6,000 plant species. He established the binomial nomenclature, which has been used in the naming of living things ever since.

Subdisciplines of botany

Form and function

Eight key subdisciplines involve the study of different aspects of plants. These disciplines are genetics, systematics, cytology, anatomy, morphology, physiology, pathology, and ecology.

Genetics is the study of heredity, genes, and gene function. Much modern botany has put to use plant [[DNA|deoxyribonucleic acid (DNA)]] and genomic information to study plants more rigorously. Molecular biology has allowed for taxonomists to categorize plant species based on DNA. Plants have been classified into different families and renamed as a result. For this reason, older botanical guides may contain outdated names and classifications. A considerable amount of new knowledge today is being generated from studying model plants like Arabidopsis thaliana (mustard weed). Mustard weed was one of the first plants to have its genome sequenced. The sequencing of the rice genome and a large international research community have made rice the de facto cereal/grass/monocot model. Another grass species, Brachypodium distachyon is also emerging as an experimental model for understanding the genetic, cellular and molecular biology of temperate grasses. Other commercially important staple foods like wheat, maize, barley, rye, millet and soybean are also having their genomes sequenced. Some of these are challenging to sequence because they have more than two haploid (n) sets of chromosomes, a condition known as polyploidy, common in the plant kingdom. The "Green Yeast" Chlamydomonas reinhardtii (a single-celled, green algae) is another plant model organism that has been extensively studied and provided important insights into cell biology.

Systematics is the study of the diversity of organism characteristics, and especially how they relate evolutionarily, establishing their phylogeny. The term "systematics" may or may not overlap with "taxonomy", which concerns itself with scientific classification of species and other taxa. Recent developments are cladistics and molecular systematics.

Cytology is the study of cells, including their function, structure, and life history.

Anatomy is the study of the interior structure of living things.

Morphology is the study of the exterior form of plants, including the placement stems and leaves on a stem (i.e. alternate or opposite), and also the study of life histories and evolutionary development. Botanical field guides often rely on plant morphology to help biologists identify plant species in the field.

Plant physiology is the study of the function of plants and their cells and tissues. Examples of physiological research includes the study of photosynthetic pathways in different plants and mineral uptake by plants.

Pathology is the study of diseases and the structural and funcional changes that occur with diseases. This can be important for range of fields, including conservation biology, ecology, agriculture, and horticulture.

Ecology is the study of interactions between organisms and their biotic and abiotic environment as an integrated system (Chapin et al. 2002).

Other subdisciplines

Other subdisciplines of botany include ethnobotany, the study of how a particular culture, or region has made use of local and indigenous plants, including their use for food, shelter, medicine, clothing, hunting and religion. While ethnobotany has its roots in botany, ethnobotanists also receive training in anthropology, sociology, history, religion, or mythology.

Paleobotany is the study of fossil plants. Palynology, the study of modern and fossil pollen, is also often grouped with paleobotany. Paleobotany and palynology are both instrumental in studying paleoclimatology.

Bryology is the study of mosses, liverworts, and hornworts; phycology is the study of algae; pteridolgy is the study of ferns; and mycology is the study of fungi.

Scope and importance of botany

As with other life forms in biology, plant life can be studied from different perspectives, from the molecular, genetic and biochemical level through organelles, cells, tissues, organs, individuals, plant populations, and communities of plants. At each of these levels a botanist might be concerned with the classification (taxonomy), structure (anatomy), or function (physiology) of plant life.

Historically, botany covers all organisms that were not considered to be animals. Some of these "plant-like" organisms include fungi (studied in mycology), bacteria and viruses (studied in microbiology), and algae (studied in phycology). Most algae, fungi, and microbes are no longer considered to be in the plant kingdom. However, attention is still given to them by botanists, and bacteria, fungi, and algae are usually covered in introductory botany courses.

Plants are a fundamental part of life on earth. They generate the oxygen, food, fibers, fuel and medicine that allow higher life forms to exist. Plants also absorb carbon dioxide, a significant greenhouse gas, through photosynthesis. A good understanding of plants is crucial to the future of human societies as it allows us to:

  • Feed the world
  • Understand fundamental life processes
  • Utilise medicine and materials
  • Understand environmental changes
  • Maintain ecological biodiversity and ecosystem function

Feed the world

Nearly all the food we eat comes (directly and indirectly) from plants like this American long grain rice.

Virtually all of the food we eat comes from plants, either directly from staple foods and other fruit and vegetables, or indirectly through livestock, which rely on plants for fodder. In other words, plants are at the base of nearly all food chains, or what ecologists call the first trophic level. Understanding how plants produce the food we eat is therefore important to be able to feed the world and provide food security for future generations, for example through plant breeding. Not all plants are beneficial to humans, some weeds are a considerable problem in agriculture, and botany provides some of the basic science in order to understand how to minimise their impact. However, other weeds are pioneer plants, which start an abused environment back on the road to rehabilitation, underlining that the term 'weed' is a very relative concept, and that broadly defined a weed is simply a plant which is too successful.

Gregor Mendel laid the foundations of genetics from his studies of plants.

Understand fundamental life processes

Plants are convenient organisms in which fundamental life processes (like cell division and protein synthesis for example) can be studied, without the ethical dilemmas of studying animals or humans. The genetic laws of inheritance were discovered in this way by Gregor Mendel, who was studying the way pea shape is inherited. What Mendel learned from studying plants has had far reaching benefits outside of botany. Barbara McClintock discovered transposons, or 'jumping genes,' by studying maize (McClintock 1950). These transposons, genes that move from one location to the next on a chromosome, are responsible for the mottled look of maize grains. This sort of research has paved the way for the study of other plant genomes and genome evolution (Fedoroff 2000). Other types of physiological research, including the uptake of carbon by plants through photosynthesis and understanding the physiology behind C3 versus C4 photosynthetic plants, are important for understanding the response of plants to climate change and the feedback mechanisms that occur with increased greenhouse gases in the atmosphere. These are a few examples that demonstrate how botanical research has an ongoing relevance to the understanding of fundamental biological processes.

Utilise medicine and materials

Many of our medicine and recreational drugs, like cannabis, caffeine, and nicotine come directly from the plant kingdom. Aspirin, which originally came from the bark of willow trees, is just one example of a plant derivative used in modern medicine. Pharmacognosy is the study of medicinal and toxic plant derivatives. There may be many novel cures for diseases provided by plants that have not yet been discovered. Popular stimulants like coffee, chocolate, tobacco, and tea also come from plants. Most alcoholic beverages come from fermenting plants such as barley malt and grapes.


Plants also provide us with many natural materials, such as cotton, wood, paper, linen, vegetable oils, some types of rope, and rubber. The production of silk would not be possible without the cultivation of the mulberry plant. Sugarcane and other plants have recently been put to use as sources of biofuels, which are important alternatives to fossil fuels. Plants are extremely valuable as recreation for millions of people who enjoy gardening, horticultural and culinary uses of plants every day.

Understand environmental changes

Plants can also help us understand changes in on our environment in many ways.

  • Understanding habitat destruction and species extinction is dependent on an accurate and complete catalogue of plant systematics and taxonomy.
  • Plant responses to ultraviolet radiation can help us monitor problems like ozone depletion (Caldwell 1981).
  • Analysing pollen deposited by plants thousands or millions of years ago can help scientists to reconstruct past climates and predict future ones, an essential part of climate change research (see Paleobotany, Paleoclimatology).
  • Recording and analysing the timing of plant life cycles are important parts of phenology used in climate-change research.
  • Plants can act a bit like the 'miner's canary', an early warning system, alerting us to important changes in our environment. For example, lichen, which are sensitive to atmospheric conditions, have been extensively used as pollution indicators.

References
ISBN links support NWE through referral fees

  • U.S. Geological Survey. National Biological Information Infrastructure: Botany
  • Caldwell, M. M. 1981. "Plant response to solar ultraviolet radiation." Physiological plant ecology I. Encyclopedia of Plant Physiology New Series. Vol. 12A, 169-197.Berlin: Springer-Verlag.
  • Chapin, Stuart F., Pamela A. Matson, Harold A. Mooney. 2002. Principles of Terrestrial Ecosystem Ecology. New York: Springer.
  • Fedoroff, Nina. 2000. "Transposons and genome evolution in plants." Proceedings of the National Academy of Sciences. 97(13), 7002-7007.
  • McClintock, Barbara. 1950. "The origin and behavior of mutable loci in maize." Proceedings of the National Academy of Sciences. V. 36(6), 344-355.

Further reading

Popular science style books on Botany

  • Bellamy, D Bellamy on Botany, ISBN 0563106662 an accessible and short introduction to various botanical subjects
  • Capon, B: Botany for Gardeners ISBN 0881926558
  • Cohen, J. How many people can the earth support? W.W. Norton 1995 ISBN 0393314952
  • Halle, Francis. In praise of plants ISBN 0881925500. English translation of a poetic advocacy of plants.
  • King, J. Reaching for the sun: How plants work ISBN 0521587387. A fluent introduction to how plants work.
  • Pakenham, T: Remarkable Trees of the World (2002) ISBN 0297843001
  • Pakenham, T: Meetings with Remarkable Trees (1996) ISBN 0297832557
  • Pollan, M The Botany of Desire: A Plant's-eye View of the World Bloomsbury ISBN 0747563004 Account of the co-evolution of plants and humans
  • Thomas, B.A.: The evolution of plants and flowers St Martin's Press[1981 ISBN 0312272715
  • Walker, D. Energy, Plants and Man ISBN 1870232054 A presentation of the basic concepts of photosynthesis

Academic and Scientific books on Botany

  • Buchanan, B.B., Gruissem, W & Jones, R.L. (2000) Biochemistry & molecular biology of plants. American Society of Plant Physiologists ISBN 0943088399
  • Crawford, R. M. M. (1989). Studies in plant survival. Blackwell. ISBN 063201475X
  • Crawley, M. J. (1997). Plant ecology. Blackwell Scientific. ISBN 0632036397
  • Ennos, R and Sheffield, E Plant life, Blackwell Science, ISBN 0865427372 Introduction to plant biodiversity
  • Fitter, A & Hay, R Environmental physiology of plants 3rd edition Sept 2001 Harcourt Publishers, Academic Press ISBN 0122577663
  • Lawlor, D.W. (2000) Photosynthesis BIOS ISBN 1859961576
  • Matthews, R. E. F. Fundamentals of plant virology Academic Press,1992.
  • Mauseth, J.D.: Botany : an introduction to plant biology. Jones and Bartlett Publishers, ISBN 0763721344 - A first year undergraduate level textbook
  • Raven, P.H, Evert R.H and Eichhorn, S.E: Biology of Plants, Freeman. ISBN 1572590416 - A first year undergraduate level textbook
  • Richards, P. W. (1996). The tropical rainforest. 2nd ed. C.U.P. (Pbk) ISBN 0521421942 £32.50
  • Ridge, I. (2002) Plants Oxford University Press ISBN 0199255482
  • Salisbury, FB and Ross, CW: Plant physiology Wadsworth publishing company ISBN 0534151620
  • Stace, C. A. A new flora of the British Isles. 2nd ed. C.U.P.,1997. ISBN 0521589355
  • Strange, R. L. Introduction to plant pathology. Wiley-VCH, 2003. ISBN 0470849738
  • Taiz, L. & Zeiger, E. (1998). Plant physiology. 3rd ed. August 2002 Sinauer Associates. ISBN 0878938230
  • Walter, H. (1985). Vegetation of the earth. 3rd rev. ed. Springer.
  • Willis, K (2002) The evolution of plants Oxford University Press ISBN 0198500653 £22-99

External links

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Flora and other plant catalogues or databases

General subfields within Biology
Anatomy | Biochemistry | | Botany | Cell biology | Ecology | Developmental biology | Ethnobotany | Evolutionary biology | Genetics | Ichthyology | Limnology | Medicine | Marine biology | Human biology | Microbiology | Molecular biology | Origin of life | Paleobotany | Paleoclimatology | Paleontology | Parasitology | Pathology | Physiology | Taxonomy | Zoology

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