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Does anyone know of any research/examples on Hopeful Monsters in Plants?
I define Hopeful Monsters as organisms of a species that have macroevolutions to prompt new speciations. These macroevolutions being themselves, prompted by smaller gradual microevolutions in the species. See this paper for more details. I'm interested in a plant based example, or any good recent example, if plants can not suffice. Ideally research that is easily read and recent, and useful for arguing the existence of themselves?
I am not sure what your question is but here is an example that may interest you.
- The three sunflower species Helianthus anomalus, H. deserticola, and H. paradoxus are all of hybrid origin of the same two "parent species" (H. annuus and H. petiolaris).
Major ecological transitions in wild sunflowers facilitated by hybridization is a paper that will likely interest you. This paper has been written by L. Riesberg and colleagues. You may want to read through some of the work of L. Rieseberg (CactusWoman already linked one of his articles).
One example of what you may consider to be a macroevolutionary change is a whole-genome-duplication, or polyploidy event. These are not uncommon in plants, and can promote speciation due to a reproductive barrier arising between the polyploid progeny and the diploid parents. You can find many papers about this topic, here is one from 2009: http://www.pnas.org/content/106/33/13875.short
Birds as Symbols and Omens
From ancient times to the present, certain birds have been considered both symbols and forecasters of events. These eight birds, from every part of the world, have been especially important.
Cranes are revered in Asia as symbols of long life.
Cuckoos are welcomed as a sign of spring in Europe and are considered omens of a happy marriage.
Doves symbolize love and peace. To dream of doves means happiness is at hand.
Eagles are considered sacred by Native Americans. The claws and bones of the birds are believed to drive illness away. As the symbol of the U.S., the bald eagle stands for endurance, independence, and courage.
Owls are considered prophets of doom. In ancient Rome as well as modern European and American folklore, a hooting owl warns of death.
The phoenix is a mythical bird that dies by fire, then rises from its own ashes after 500 years! Thus it symbolizes renewed life.
Ravens have been reverred by sailors, especially Viking explorers, for their ability to find land. Other cultures believe ravens can predict death and pestilence (disease). Folklore has it that the raven's sense of smell is so acute that it can smell death before it comes.
In any ecosystem, species eat and are eaten by other species. A food chain is a simple pathway that connects up to six species by what they eat. It describes the route followed by energy and nutrients as they are passed from organism to organism.
WHAT IS A FOOD WEB?
The community within an ecosystem can contain thousands of species. Each species may be part of two or more food chains. The interconnected network of food chains in an ecosystem is called a food web. It includes producers that make their own food by photosynthesis, consumers that eat plants or animals, and decomposers that break down dead organisms.
WHY ARE THERE FEWER PREDATORS THAN PREY?
Predators are fewer in number than prey because they are higher up the food chain. In a food chain, an organism passes on only part of the energy it receives from food. With less energy, each level in a food chain supports fewer individuals than the one below it.
HABITAT AND DIET
Gila monsters are solitary and live in desert and semi-desert areas with just enough moisture to support a few shrubs. Gila monster burrows are commonly found in rocky foothills, as they avoid open areas. The lizards can adjust their behavior according to the temperature. Gila monsters may be active at night if temperatures are extremely hot during the day or be crepuscular or diurnal if the temperature is optimal for them.
Gila monsters walk high on their short legs, with the tail clear of the ground and swinging from side to side for balance, in what looks like an awkward gait. Their speed is not great, but the monsters keep at it. Good climbers, Gila monsters are often found fairly high up in cholla cactus foraging for bird eggs in nests.
During cold winter months, Gila monsters stay in burrows dug with their stout claws or even burrows of desert tortoises and have fat stores in their tail to keep them alive during this time. When springtime comes, they begin to hunt again.
As carnivores, Gila monsters do not have very good eyesight when they hunt, they use their senses of taste and smell. To track prey, the Gila monster flicks its forked tongue out to pick up scent particles in the air. These lizards are not very fast, so they need to sneak up on prey and bite them before they get away. Their prey includes birds’ eggs and nestlings, rodents, frogs, lizards, insects, centipedes, and worms they may also eat carrion.
Gila monsters don’t chew their food but instead just swallow it whole however, they do break open eggs. The monster’s venomous saliva may be more useful as a defense against predators rather than for hunting, because most of the lizard’s prey is small enough to be subdued by the strength of the bite. There is no antivenom for Gila monster bites.
At the San Diego Zoo, the Gila monsters are fed mice and hard-boiled eggs.
The word green comes from the Middle English and Old English word grene, which, like the German word grün, has the same root as the words grass and grow.  It is from a Common Germanic *gronja-, which is also reflected in Old Norse grænn, Old High German gruoni (but unattested in East Germanic), ultimately from a PIE root * ghre- "to grow", and root-cognate with grass and to grow.  The first recorded use of the word as a color term in Old English dates to ca. AD 700. 
Latin with viridis also has a genuine and widely used term for "green". Related to virere "to grow" and ver "spring", it gave rise to words in several Romance languages, French vert, Italian verde (and English vert, verdure etc.).  Likewise the Slavic languages with zelenъ. Ancient Greek also had a term for yellowish, pale green – χλωρός, chloros (cf. the color of chlorine), cognate with χλοερός "verdant" and χλόη "chloe, the green of new growth".
Thus, the languages mentioned above (Germanic, Romance, Slavic, Greek) have old terms for "green" which are derived from words for fresh, sprouting vegetation. However, comparative linguistics makes clear that these terms were coined independently, over the past few millennia, and there is no identifiable single Proto-Indo-European or word for "green". For example, the Slavic zelenъ is cognate with Sanskrit hari "yellow, ochre, golden".  The Turkic languages also have jašɨl "green" or "yellowish green", compared to a Mongolian word for "meadow". 
Languages where green and blue are one color
In some languages, including old Chinese, Thai, old Japanese, and Vietnamese, the same word can mean either blue or green.  The Chinese character 青 (pronounced qīng in Mandarin, ao in Japanese, and thanh in Sino-Vietnamese) has a meaning that covers both blue and green blue and green are traditionally considered shades of "青". In more contemporary terms, they are 藍 (lán, in Mandarin) and 綠 (lǜ, in Mandarin) respectively. Japanese also has two terms that refer specifically to the color green, 緑 (midori, which is derived from the classical Japanese descriptive verb midoru "to be in leaf, to flourish" in reference to trees) and グリーン (guriin, which is derived from the English word "green"). However, in Japan, although the traffic lights have the same colors as other countries have, the green light is described using the same word as for blue, aoi, because green is considered a shade of aoi similarly, green variants of certain fruits and vegetables such as green apples, green shiso (as opposed to red apples and red shiso) will be described with the word aoi. Vietnamese uses a single word for both blue and green, xanh, with variants such as xanh da trời (azure, lit. "sky blue"), lam (blue), and lục (green also xanh lá cây, lit. "leaf green").
"Green" in modern European languages corresponds to about 520–570 nm, but many historical and non-European languages make other choices, e.g. using a term for the range of ca. 450–530 nm ("blue/green") and another for ca. 530–590 nm ("green/yellow"). [ citation needed ] In the comparative study of color terms in the world's languages, green is only found as a separate category in languages with the fully developed range of six colors (white, black, red, green, yellow, and blue), or more rarely in systems with five colors (white, red, yellow, green, and black/blue).  (See distinction of green from blue)  These languages have introduced supplementary vocabulary to denote "green", but these terms are recognizable as recent adoptions that are not in origin color terms (much like the English adjective orange being in origin not a color term but the name of a fruit). Thus, the Thai word เขียว kheīyw, besides meaning "green", also means "rank" and "smelly" and holds other unpleasant associations. 
The Celtic languages had a term for "blue/green/grey", Proto-Celtic *glasto-, which gave rise to Old Irish glas "green, grey" and to Welsh glas "blue". This word is cognate with the Ancient Greek γλαυκός "bluish green", contrasting with χλωρός "yellowish green" discussed above.
In modern Japanese, the term for green is 緑, while the old term for "blue/green", blue ( 青 , Ao) now means "blue". But in certain contexts, green is still conventionally referred to as 青, as in blue traffic light ( 青信号 , ao shingō) and blue leaves ( 青葉 , aoba) , reflecting the absence of blue-green distinction in old Japanese (more accurately, the traditional Japanese color terminology grouped some shades of green with blue, and others with yellow tones).
Color vision and colorimetry
In optics, the perception of green is evoked by light having a spectrum dominated by energy with a wavelength of roughly 495–570 nm. The sensitivity of the dark-adapted human eye is greatest at about 507 nm, a blue-green color, while the light-adapted eye is most sensitive about 555 nm, a yellow-green these are the peak locations of the rod and cone (scotopic and photopic, respectively) luminosity functions. 
The perception of greenness (in opposition to redness forming one of the opponent mechanisms in human color vision) is evoked by light which triggers the medium-wavelength M cone cells in the eye more than the long-wavelength L cones. Light which triggers this greenness response more than the yellowness or blueness of the other color opponent mechanism is called green. A green light source typically has a spectral power distribution dominated by energy with a wavelength of roughly 487–570 nm. 
Human eyes have color receptors known as cone cells, of which there are three types. In some cases, one is missing or faulty, which can cause color blindness, including the common inability to distinguish red and yellow from green, known as deuteranopia or red–green color blindness.  Green is restful to the eye. Studies show that a green environment can reduce fatigue. 
In the subtractive color system, used in painting and color printing, green is created by a combination of yellow and blue, or yellow and cyan in the RGB color model, used on television and computer screens, it is one of the additive primary colors, along with red and blue, which are mixed in different combinations to create all other colors. On the HSV color wheel, also known as the RGB color wheel, the complement of green is magenta that is, a color corresponding to an equal mixture of red and blue light (one of the purples). On a traditional color wheel, based on subtractive color, the complementary color to green is considered to be red. 
In additive color devices such as computer displays and televisions, one of the primary light sources is typically a narrow-spectrum yellowish-green of dominant wavelength
550 nm this "green" primary is combined with an orangish-red "red" primary and a purplish-blue "blue" primary to produce any color in between – the RGB color model. A unique green (green appearing neither yellowish nor bluish) is produced on such a device by mixing light from the green primary with some light from the blue primary.
Lasers emitting in the green part of the spectrum are widely available to the general public in a wide range of output powers. Green laser pointers outputting at 532 nm (563.5 THz) are relatively inexpensive compared to other wavelengths of the same power, and are very popular due to their good beam quality and very high apparent brightness. The most common green lasers use diode pumped solid state (DPSS) technology to create the green light.  An infrared laser diode at 808 nm is used to pump a crystal of neodymium-doped yttrium vanadium oxide (Nd:YVO4) or neodymium-doped yttrium aluminium garnet (Nd:YAG) and induces it to emit 281.76 THz (1064 nm). This deeper infrared light is then passed through another crystal containing potassium, titanium and phosphorus (KTP), whose non-linear properties generate light at a frequency that is twice that of the incident beam (563.5 THz) in this case corresponding to the wavelength of 532 nm ("green").  Other green wavelengths are also available using DPSS technology ranging from 501 nm to 543 nm.  Green wavelengths are also available from gas lasers, including the helium–neon laser (543 nm), the Argon-ion laser (514 nm) and the Krypton-ion laser (521 nm and 531 nm), as well as liquid dye lasers. Green lasers have a wide variety of applications, including pointing, illumination, surgery, laser light shows, spectroscopy, interferometry, fluorescence, holography, machine vision, non-lethal weapons and bird control. 
As of mid-2011, direct green laser diodes at 510 nm and 500 nm have become generally available,  although the price remains relatively prohibitive for widespread public use. The efficiency of these lasers (peak 3%) [ citation needed ] compared to that of DPSS green lasers (peak 35%) [ citation needed ]  may also be limiting adoption of the diodes to niche uses.
Pigments, food coloring and fireworks
Many minerals provide pigments which have been used in green paints and dyes over the centuries. Pigments, in this case, are minerals which reflect the color green, rather that emitting it through luminescent or phosphorescent qualities. The large number of green pigments makes it impossible to mention them all. Among the more notable green minerals, however is the emerald, which is colored green by trace amounts of chromium and sometimes vanadium.  Chromium(III) oxide (Cr2O3), is called chrome green, also called viridian or institutional green when used as a pigment.  For many years, the source of amazonite's color was a mystery. Widely thought to have been due to copper because copper compounds often have blue and green colors, the blue-green color is likely to be derived from small quantities of lead and water in the feldspar.  Copper is the source of the green color in malachite pigments, chemically known as basic copper(II) carbonate. 
Verdigris is made by placing a plate or blade of copper, brass or bronze, slightly warmed, into a vat of fermenting wine, leaving it there for several weeks, and then scraping off and drying the green powder that forms on the metal. The process of making verdigris was described in ancient times by Pliny. It was used by the Romans in the murals of Pompeii, and in Celtic medieval manuscripts as early as the 5th century AD. It produced a blue-green which no other pigment could imitate, but it had drawbacks: it was unstable, it could not resist dampness, it did not mix well with other colors, it could ruin other colors with which it came into contact, and it was toxic. Leonardo da Vinci, in his treatise on painting, warned artists not to use it. It was widely used in miniature paintings in Europe and Persia in the 16th and 17th centuries. Its use largely ended in the late 19th century, when it was replaced by the safer and more stable chrome green.  Viridian, as described above, was patented in 1859. It became popular with painters, since, unlike other synthetic greens, it was stable and not toxic. Vincent van Gogh used it, along with Prussian blue, to create a dark blue sky with a greenish tint in his painting Café Terrace at Night. 
Green earth is a natural pigment used since the time of the Roman Empire. It is composed of clay colored by iron oxide, magnesium, aluminum silicate, or potassium. Large deposits were found in the South of France near Nice, and in Italy around Verona, on Cyprus, and in Bohemia. The clay was crushed, washed to remove impurities, then powdered. It was sometimes called Green of Verona. 
Mixtures of oxidized cobalt and zinc were also used to create green paints as early as the 18th century. 
Cobalt green, sometimes known as Rinman's green or zinc green, is a translucent green pigment made by heating a mixture of cobalt (II) oxide and zinc oxide. Sven Rinman, a Swedish chemist, discovered this compound in 1780.  Green chrome oxide was a new synthetic green created by a chemist named Pannetier in Paris in about 1835. Emerald green was a synthetic deep green made in the 19th century by hydrating chrome oxide. It was also known as Guignet green. 
There is no natural source for green food colorings which has been approved by the US Food and Drug Administration. Chlorophyll, the E numbers E140 and E141, is the most common green chemical found in nature, and only allowed in certain medicines and cosmetic materials.  Quinoline Yellow (E104) is a commonly used coloring in the United Kingdom but is banned in Australia, Japan, Norway and the United States.  Green S (E142) is prohibited in many countries, for it is known to cause hyperactivity, asthma, urticaria, and insomnia. 
To create green sparks, fireworks use barium salts, such as barium chlorate, barium nitrate crystals, or barium chloride, also used for green fireplace logs.  Copper salts typically burn blue, but cupric chloride (also known as "campfire blue") can also produce green flames.  Green pyrotechnic flares can use a mix ratio 75:25 of boron and potassium nitrate.  Smoke can be turned green by a mixture: solvent yellow 33, solvent green 3, lactose, magnesium carbonate plus sodium carbonate added to potassium chlorate. 
The chloroplasts of plant cells contain a high concentration of chlorophyll, making them appear green.
Frogs often appear green because light reflects off of a blue underlayer through a yellow upperlayer, filtering the light to be primarily green.
A yellow-naped Amazon parrot, colored green for camouflage in the jungle
The green huntsman spider is green due to the presence of bilin pigments in the spider's hemolymph and tissue fluids
Green is common in nature, as many plants are green because of a complex chemical known as chlorophyll, which is involved in photosynthesis. Chlorophyll absorbs the long wavelengths of light (red) and short wavelengths of light (blue) much more efficiently than the wavelengths that appear green to the human eye, so light reflected by plants is enriched in green.  Chlorophyll absorbs green light poorly because it first arose in organisms living in oceans where purple halobacteria were already exploiting photosynthesis. Their purple color arose because they extracted energy in the green portion of the spectrum using bacteriorhodopsin. The new organisms that then later came to dominate the extraction of light were selected to exploit those portions of the spectrum not used by the halobacteria. 
Animals typically use the color green as camouflage, blending in with the chlorophyll green of the surrounding environment.  Most fish, reptiles, amphibians, and birds appear green because of a reflection of blue light coming through an over-layer of yellow pigment. Perception of color can also be affected by the surrounding environment. For example, broadleaf forests typically have a yellow-green light about them as the trees filter the light. Turacoverdin is one chemical which can cause a green hue in birds, especially.  Invertebrates such as insects or mollusks often display green colors because of porphyrin pigments, sometimes caused by diet. This can causes their feces to look green as well. Other chemicals which generally contribute to greenness among organisms are flavins (lychochromes) and hemanovadin.  Humans have imitated this by wearing green clothing as a camouflage in military and other fields. Substances that may impart a greenish hue to one's skin include biliverdin, the green pigment in bile, and ceruloplasmin, a protein that carries copper ions in chelation.
The green huntsman spider is green due to the presence of bilin pigments in the spider's hemolymph (circulatory system fluids) and tissue fluids.  It hunts insects in green vegetation, where it is well camouflaged.
There is no green pigment in green eyes like the color of blue eyes, it is an optical illusion its appearance is caused by the combination of an amber or light brown pigmentation of the stroma, given by a low or moderate concentration of melanin, with the blue tone imparted by the Rayleigh scattering of the reflected light.  Nobody is brought into the world with green eyes. An infant has one of two eye hues: dark or blue. Following birth, cells called melanocytes start to discharge melanin, the earthy colored shade, in the child's irises. This beginnings happening since melanocytes respond to light in time.  Green eyes are most common in Northern and Central Europe.   They can also be found in Southern Europe, West Asia, Central Asia, and South Asia. [ citation needed ] In Iceland, 89% of women and 87% of men have either blue or green eye color.  A study of Icelandic and Dutch adults found green eyes to be much more prevalent in women than in men.  Among European Americans, green eyes are most common among those of recent Celtic and Germanic ancestry, about 16%. 
Neolithic cave paintings do not have traces of green pigments, but neolithic peoples in northern Europe did make a green dye for clothing, made from the leaves of the birch tree. It was of very poor quality, more brown than green. Ceramics from ancient Mesopotamia show people wearing vivid green costumes, but it is not known how the colors were produced. 
The gardens of ancient Egypt were symbols of rebirth. Tomb painting of the gardens of Amon at the temple of Karnak, from the tomb of Nakh, the chief gardener. Early 14th century BC.
The Ancient Egyptian god Osiris, ruler of the underworld and of rebirth and regeneration, was typically shown with a green face. (Tomb of Nefertari, 1295–1253 BC)
Ancient Roman fresco of Flora, or Spring, from Stabiae (2nd century AD)
In Ancient Egypt, green was the symbol of regeneration and rebirth, and of the crops made possible by the annual flooding of the Nile. For painting on the walls of tombs or on papyrus, Egyptian artists used finely ground malachite, mined in the west Sinai and the eastern desert a paintbox with malachite pigment was found inside the tomb of King Tutankhamun. They also used less expensive green earth pigment, or mixed yellow ochre and blue azurite. To dye fabrics green, they first colored them yellow with dye made from saffron and then soaked them in blue dye from the roots of the woad plant. 
For the ancient Egyptians, green had very positive associations. The hieroglyph for green represented a growing papyrus sprout, showing the close connection between green, vegetation, vigor and growth. In wall paintings, the ruler of the underworld, Osiris, was typically portrayed with a green face, because green was the symbol of good health and rebirth. Palettes of green facial makeup, made with malachite, were found in tombs. It was worn by both the living and the dead, particularly around the eyes, to protect them from evil. Tombs also often contained small green amulets in the shape of scarab beetles made of malachite, which would protect and give vigor to the deceased. It also symbolized the sea, which was called the "Very Green." 
In Ancient Greece, green and blue were sometimes considered the same color, and the same word sometimes described the color of the sea and the color of trees. The philosopher Democritus described two different greens: cloron, or pale green, and prasinon, or leek green. Aristotle considered that green was located midway between black, symbolizing the earth, and white, symbolizing water. However, green was not counted among the four classic colors of Greek painting – red, yellow, black and white – and is rarely found in Greek art. 
The Romans had a greater appreciation for the color green it was the color of Venus, the goddess of gardens, vegetables and vineyards. The Romans made a fine green earth pigment that was widely used in the wall paintings of Pompeii, Herculaneum, Lyon, Vaison-la-Romaine, and other Roman cities. They also used the pigment verdigris, made by soaking copper plates in fermenting wine.  By the second century AD, the Romans were using green in paintings, mosaics and glass, and there were ten different words in Latin for varieties of green. 
In the Arnolfini portrait by Jan van Eyck (1434), the rich green fabric of the dress showed the wealth and status of the family.
Duccio di Buoninsegna painted the faces in this painting (1308–1311) with an undercoat of green earth pigment. The surface pink has faded, making the faces look green today.
The green costume of the Mona Lisa shows she was from the gentry, not from the nobility.
In the 15th century Saint Wolfgang and the Devil by Michael Pacher, the Devil is green. Poets such as Chaucer also drew connections between the color green and the devil. 
In this 1503 painting by Perugino, malachite pigment was used to paint the bright green garments of the worshippers, while the background greens were painted in green earth pigments.
In the Middle Ages and Renaissance, the color of clothing showed a person's social rank and profession. Red could only be worn by the nobility, brown and gray by peasants, and green by merchants, bankers and the gentry and their families. The Mona Lisa wears green in her portrait, as does the bride in the Arnolfini portrait by Jan van Eyck.
There were no good vegetal green dyes which resisted washing and sunlight for those who wanted or were required to wear green. Green dyes were made out of the fern, plantain, buckthorn berries, the juice of nettles and of leeks, the digitalis plant, the broom plant, the leaves of the fraxinus, or ash tree, and the bark of the alder tree, but they rapidly faded or changed color. Only in the 16th century was a good green dye produced, by first dyeing the cloth blue with woad, and then yellow with Reseda luteola, also known as yellow-weed. 
The pigments available to painters were more varied monks in monasteries used verdigris, made by soaking copper in fermenting wine, to color medieval manuscripts. They also used finely-ground malachite, which made a luminous green. They used green earth colors for backgrounds.
During the early Renaissance, painters such as Duccio di Buoninsegna learned to paint faces first with a green undercoat, then with pink, which gave the faces a more realistic hue. Over the centuries the pink has faded, making some of the faces look green. 
In the 18th and 19th century
Dedham Vale (1802) by John Constable. The paintings of Constable romanticized the vivid green landscapes of England
In the painting of Jean-Baptiste Debret (1822), Emperor Pedro I of Brazil wearing the imperial mantle decorated with green fabric.
In the paintings of Jean-Baptiste-Camille Corot (1796–1875), the green of trees and nature became the central element of the painting, with the people secondary
The Night Café, (1888), by Vincent van Gogh, used red and green to express what Van Gogh called "the terrible human passions."
Émile Bernard – Still life with green teapot, cup and fruit, 1890
Louis Anquetin – Woman at the Champs-Élysées by night
The 18th and 19th centuries brought the discovery and production of synthetic green pigments and dyes, which rapidly replaced the earlier mineral and vegetable pigments and dyes. These new dyes were more stable and brilliant than the vegetable dyes, but some contained high levels of arsenic, and were eventually banned.
In the 18th and 19th centuries, green was associated with the romantic movement in literature and art.  The German poet and philosopher Goethe declared that green was the most restful color, suitable for decorating bedrooms. Painters such as John Constable and Jean-Baptiste-Camille Corot depicted the lush green of rural landscapes and forests. Green was contrasted to the smoky grays and blacks of the Industrial Revolution.
The second half of the 19th century saw the use of green in art to create specific emotions, not just to imitate nature. One of the first to make color the central element of his picture was the American artist James McNeil Whistler, who created a series of paintings called "symphonies" or "noctures" of color, including Symphony in gray and green The Ocean between 1866 and 1872.
The late 19th century also brought the systematic study of color theory, and particularly the study of how complementary colors such as red and green reinforced each other when they were placed next to each other. These studies were avidly followed by artists such as Vincent van Gogh. Describing his painting, The Night Cafe, to his brother Theo in 1888, Van Gogh wrote: "I sought to express with red and green the terrible human passions. The hall is blood red and pale yellow, with a green billiard table in the center, and four lamps of lemon yellow, with rays of orange and green. Everywhere it is a battle and antithesis of the most different reds and greens." 
In the 20th and 21st century
In the 1980s green became a political symbol, the color of the Green Party in Germany and in many other European countries. It symbolized the environmental movement, and also a new politics of the left which rejected traditional socialism and communism. (See § In politics section below.)
Safety and permission
Green can communicate safety to proceed, as in traffic lights.  Green and red were standardized as the colors of international railroad signals in the 19th century.  The first traffic light, using green and red gas lamps, was erected in 1868 in front of the Houses of Parliament in London. It exploded the following year, injuring the policeman who operated it. In 1912, the first modern electric traffic lights were put up in Salt Lake City, Utah. Red was chosen largely because of its high visibility, and its association with danger, while green was chosen largely because it could not be mistaken for red. Today green lights universally signal that a system is turned on and working as it should. In many video games, green signifies both health and completed objectives, opposite red.
Nature, vivacity, and life
Green is the color most commonly associated in Europe and the United States with nature, vivacity and life.  It is the color of many environmental organizations, such as Greenpeace, and of the Green Parties in Europe. Many cities have designated a garden or park as a green space, and use green trash bins and containers. A green cross is commonly used to designate pharmacies in Europe.
In China, green is associated with the east, with sunrise, and with life and growth.  In Thailand, the color green is considered auspicious for those born on a Wednesday (light green for those born at night). 
Springtime, freshness, and hope
Green is the color most commonly associated in the United States and Europe with springtime, freshness, and hope.  [b] Green is often used to symbolize rebirth and renewal and immortality. In Ancient Egypt the god Osiris, king of the underworld, was depicted as green-skinned.  Green as the color of hope is connected with the color of springtime hope represents the faith that things will improve after a period of difficulty, like the renewal of flowers and plants after the winter season. 
Youth and inexperience
Green the color most commonly associated in Europe and the United States with youth. It also often is used to describe anyone young, inexperienced, probably by the analogy to immature and unripe fruit.   [c] Examples include green cheese, a term for a fresh, unaged cheese, and greenhorn, an inexperienced person.
Calm, tolerance, and the agreeable
Surveys also show that green is the color most associated with the calm, the agreeable, and tolerance. Red is associated with heat, blue with cold, and green with an agreeable temperature. Red is associated with dry, blue with wet, and green, in the middle, with dampness. Red is the most active color, blue the most passive green, in the middle, is the color of neutrality and calm, sometimes used in architecture and design for these reasons.  Blue and green together symbolize harmony and balance.  Experimental studies also show this calming effect in a significantly decrease of negative emotions  and increasing of creative performance. 
Jealousy and envy
Green is often associated with jealousy and envy. The expression "green-eyed monster" was first used by William Shakespeare in Othello: "it is the green-eyed monster which doth mock the meat it feeds on." Shakespeare also used it in the Merchant of Venice, speaking of "green-eyed jealousy." 
Love and sexuality
Green today is not commonly associated in Europe and the United States with love and sexuality,  but in stories of the medieval period it sometimes represented love  and the base, natural desires of man.  It was the color of the serpent in the Garden of Eden who caused the downfall of Adam and Eve. However, for the troubadours, green was the color of growing love, and light green clothing was reserved for young women who were not yet married. 
In Persian and Sudanese poetry, dark-skinned women, called "green" women, were considered erotic.  The Chinese term for cuckold is "to wear a green hat."  This was because in ancient China, prostitutes were called "the family of the green lantern" and a prostitute's family would wear a green headscarf. 
In Victorian England, the color green was associated with homosexuality. 
Dragons, fairies, monsters, and devils
A medieval illustration of a dragon (1460)
A 20th-century depiction of a leprechaun
In legends, folk tales and films, fairies, dragons, monsters, and the devil are often shown as green.
In the Middle Ages, the devil was usually shown as either red, black or green. Dragons were usually green, because they had the heads, claws and tails of reptiles.
Modern Chinese dragons are also often green, but unlike European dragons, they are benevolent Chinese dragons traditionally symbolize potent and auspicious powers, particularly control over water, rainfall, hurricane, and floods. The dragon is also a symbol of power, strength, and good luck. The Emperor of China usually used the dragon as a symbol of his imperial power and strength. The dragon dance is a popular feature of Chinese festivals.
In Irish folklore and English folklore, the color was sometimes was associated with witchcraft, and with faeries and spirits.  The type of Irish fairy known as a leprechaun is commonly portrayed wearing a green suit, though before the 20th century he was usually described as wearing a red suit.
In theater and film, green was often connected with monsters and the inhuman. The earliest films of Frankenstein were in black and white, but in the poster for the 1935 version The Bride of Frankenstein, the monster had a green face. Actor Bela Lugosi wore green-hued makeup for the role of Dracula in the 1927–1928 Broadway stage production.  
Poison and sickness
Like other common colors, green has several completely opposite associations. While it is the color most associated by Europeans and Americans with good health, it is also the color most often associated with toxicity and poison. There was a solid foundation for this association in the nineteenth century several popular paints and pigments, notably verdigris, vert de Schweinfurt and vert de Paris, were highly toxic, containing copper or arsenic.  [d] The intoxicating drink absinthe was known as "the green fairy".
A green tinge in the skin is sometimes associated with nausea and sickness.  The expression 'green at the gills' means appearing sick. The color, when combined with gold, is sometimes seen as representing the fading of youth.  In some Far East cultures the color green is used as a symbol of sickness or nausea. 
Social status, prosperity and the dollar
The reverse of the United States one-dollar bill has been green since 1861, giving it the popular name greenback.
Green in Europe and the United States is sometimes associated with status and prosperity. From the Middle Ages to the 19th century it was often worn by bankers, merchants country gentlemen and others who were wealthy but not members of the nobility. The benches in the House of Commons of the United Kingdom, where the landed gentry sat, are colored green.
In the United States green was connected with the dollar bill. Since 1861, the reverse side of the dollar bill has been green. Green was originally chosen because it deterred counterfeiters, who tried to use early camera equipment to duplicate banknotes. Also, since the banknotes were thin, the green on the back did not show through and muddle the pictures on the front of the banknote. Green continues to be used because the public now associates it with a strong and stable currency. 
One of the more notable uses of this meaning is found in The Wonderful Wizard of Oz. The Emerald City in this story is a place where everyone wears tinted glasses that make everything appear green. According to the populist interpretation of the story, the city's color is used by the author, L. Frank Baum, to illustrate the financial system of America in his day, as he lived in a time when America was debating the use of paper money versus gold. 
The flag of Italy (1797) was modeled after the flag of France. It was originally the flag of the Cisalpine Republic, and the green came from the uniforms of the army of Milan.
The flag of Brazil (1889). The green color was inherited from the flag of the Empire of Brazil, where it represented the color of the House of Braganza.
The flag of Ireland (1919). The green represents the culture and traditions of Gaelic Ireland.  
The Flag of Saudi Arabia (1932) has the green color of Islam. The inscription in Arabic says: There is no God but Allah, and Muhammad is his Prophet,"
The flag of India (1947). The green has been said at different times to represent the Muslim community, hope, or prosperity.
The flag of Bangladesh (1971). The green field stands for the lushness of the land of Bangladesh
The flag of Nigeria (1960). The green represents the forests and natural wealth of the country.
The flag of Pakistan (1947). The green part represents the Muslim majority of the country.
The flag of South Africa (1994) includes green, yellow and black, the colors of the African National Congress.
The former flag of Libya (1977–2011) was the only monochromatic flag in the world, with no design or details.
- The flag of Italy (1797) was modeled after the French tricolor. It was originally the flag of the Cisalpine Republic, whose capital was Milan red and white were the colors of Milan, and green was the color of the military uniforms of the army of the Cisalpine Republic. Other versions say it is the color of the Italian landscape, or symbolizes hope. 
- The flag of Brazil has a green field adapted from the flag of the Empire of Brazil. The green represented the royal family.
- The flag of India was inspired by an earlier flag of the independence movement of Gandhi, which had a red band for Hinduism and a green band representing Islam, the second largest religion in India. 
- The flag of Pakistan symbolizes Pakistan's commitment to Islam and equal rights of religious minorities where the larger portion (3:2 ratio) of flag is dark green representing Muslim majority (98% of total population) while a white vertical bar (3:1 ratio) at the mast representing equal rights for religious minorities and minority religions in country. The crescent and star symbolizes progress and bright future respectively.
- The Flag of Bangladesh has a green field based on a similar flag used during the Bangladesh Liberation War of 1971. It consists of a red disc on top of a green field. The red disc represents the sun rising over Bengal, and also the blood of those who died for the independence of Bangladesh. The green field stands for the lushness of the land of Bangladesh.
- The flag of the international constructed languageEsperanto has a green field and a green star in a white area. The green represents hope ("esperanto" means "one who hopes"), the white represents peace and neutrality and the star represents the five inhabited continents.
Green is one of the three colors (along with red and black, or red and gold) of Pan-Africanism. Several African countries thus use the color on their flags, including Nigeria, South Africa, Ghana, Senegal, Mali, Ethiopia, Togo, Guinea, Benin, and Zimbabwe. The Pan-African colors are borrowed from the Ethiopian flag, one of the oldest independent African countries. Green on some African flags represents the natural richness of Africa. 
Many flags of the Islamic world are green, as the color is considered sacred in Islam (see below). The flag of Hamas,  as well as the flag of Iran, is green, symbolizing their Islamist ideology.  The 1977 flag of Libya consisted of a simple green field with no other characteristics. It was the only national flag in the world with just one color and no design, insignia, or other details.  Some countries used green in their flags to represent their country's lush vegetation, as in the flag of Jamaica,  and hope in the future, as in the flags of Portugal and Nigeria.  The green cedar of Lebanon tree on the Flag of Lebanon officially represents steadiness and tolerance. 
Green is a symbol of Ireland, which is often referred to as the "Emerald Isle". The color is particularly identified with the republican and nationalist traditions in modern times. It is used this way on the flag of the Republic of Ireland, in balance with white and the Protestant orange.  Green is a strong trend in the Irish holiday St. Patrick's Day. 
The green harp flag was the banner of Irish nationalism from the 17th century until the early 20th century.
The emblem of the Australian Greens. The party won 10% in the 2016 elections for the Australian Senate.
A demonstration by Les Verts, the green party of France, in Lyon.
The Rainbow Warrior, the ship of the Greenpeace environmental movement.
The first recorded green party was a political faction in Constantinople during the 6th century Byzantine Empire. which took its name from a popular chariot racing team. They were bitter opponents of the blue faction, which supported Emperor Justinian I and which had its own chariot racing team. In 532 AD rioting between the factions began after one race, which led to the massacre of green supporters and the destruction of much of the center of Constantinople.  (See Nika Riots).
Green was the traditional color of Irish nationalism, beginning in the 17th century. The green harp flag, with a traditional gaelic harp, became the symbol of the movement. It was the banner of the Society of United Irishmen, which organized the ultimately unsuccessful Irish Rebellion of 1798. When Ireland achieved independence in 1922, green was incorporated into the national flag. 
In the 1970s green became the color of the third biggest Swiss Federal Council political party, the Swiss People's Party SVP. The ideology is Swiss nationalism, national conservatism, right-wing populism, economic liberalism, agrarianism, isolationism, euroscepticism. The SVP was founded on September 22, 1971 and has 90,000 members. 
In the 1980s green became the color of a number of new European political parties organized around an agenda of environmentalism. Green was chosen for its association with nature, health, and growth. The largest green party in Europe is Alliance '90/The Greens (German: Bündnis 90/Die Grünen) in Germany, which was formed in 1993 from the merger of the German Green Party, founded in West Germany in 1980, and Alliance 90, founded during the Revolution of 1989–1990 in East Germany. In the 2009 federal elections, the party won 11% of the votes and 68 out of 622 seats in the Bundestag.
Green parties in Europe have programs based on ecology, grassroots democracy, nonviolence, and social justice. Green parties are found in over one hundred countries, and most are members of the Global Green Network. 
Greenpeace is a non-governmental environmental organization which emerged from the anti-nuclear and peace movements in the 1970s. Its ship, the Rainbow Warrior, frequently tried to interfere with nuclear tests and whaling operations. The movement now has branches in forty countries.
The Australian Greens was founded in 1992. In the 2010 federal election, the party received 13% of the vote (more than 1.6 million votes) in the Senate, a first for any Australian minor party.
Green is the color associated with Puerto Rico's Independence Party, the smallest of that country's three major political parties, which advocates Puerto Rican independence from the United States.
Green is the traditional color of Islam. According to tradition, the robe and banner of Muhammad were green, and according to the Koran (XVIII, 31 and LXXVI, 21) those fortunate enough to live in paradise wear green silk robes.    Muhammad is quoted in a hadith as saying that "water, greenery, and a beautiful face" were three universally good things. 
Al-Khidr ("The Green One"), was an important Qur'anic figure who was said to have met and traveled with Moses.  He was given that name because of his role as a diplomat and negotiator. Green was also considered to be the median color between light and obscurity. 
Roman Catholic and more traditional Protestant clergy wear green vestments at liturgical celebrations during Ordinary Time.  In the Eastern Catholic Church, green is the color of Pentecost.  Green is one of the Christmas colors as well, possibly dating back to pre-Christian times, when evergreens were worshiped for their ability to maintain their color through the winter season. Romans used green holly and evergreen as decorations for their winter solstice celebration called Saturnalia, which eventually evolved into a Christmas celebration.  In Ireland and Scotland especially, green is used to represent Catholics, while orange is used to represent Protestantism. This is shown on the national flag of Ireland.
In Paganism, green represents abundance, growth, wealth, renewal, and balance. In magickal practices, green is often used to bring money and luck. 
A baccarat palette and cards on a casino gambling table.
A billiards table, colored green after the lawns where the ancestors of the game were originally played.
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Dicotyledon, byname dicot, any member of the flowering plants, or angiosperms, that has a pair of leaves, or cotyledons, in the embryo of the seed. There are about 175,000 known species of dicots. Most common garden plants, shrubs and trees, and broad-leafed flowering plants such as magnolias, roses, geraniums, and hollyhocks are dicots.
Dicots typically also have flower parts (sepals, petals, stamens, and pistils) based on a plan of four or five, or multiples thereof, although there are exceptions. The leaves are net-veined in most, which means the vessels that conduct water and food show a meshlike pattern. In the stems the vessels are usually arranged in a continuous ring near the stem surface. About 50 percent of all dicot species are woody they show an annual increase in stem diameter as a result of the production of new tissue by the cambium, a layer of cells that remain capable of division throughout the life of these plants. Branching of stems is common, as are taproots. The microscopic pores (stomates) on the leaf surfaces are usually scattered and are in various orientations. The pollen grains typically have three germinal furrows or pores (tricolpate condition), except in the more primitive families.
The Editors of Encyclopaedia Britannica This article was most recently revised and updated by Adam Augustyn, Managing Editor, Reference Content.
Journal of Structural Biology
Journal of Structural Biology (JSB) has an open access mirror journal, the Journal of Structural Biology: X (JSBX), which has the same aims and scope, editorial board and peer-review process. To submit to Journal of Structural Biology: X visit https://www.editorialmanager.com/YJSBX/default.aspx. JSB.
Journal of Structural Biology (JSB) has an open access mirror journal, the Journal of Structural Biology: X (JSBX), which has the same aims and scope, editorial board and peer-review process. To submit to Journal of Structural Biology: X visit https://www.editorialmanager.com/YJSBX/default.aspx. JSB publishes papers dealing with the structural analysis of living material at every level of organization by all methods that lead to an understanding of biological function in terms of molecular and supermolecular structure.
Techniques covered include:
&bull Light microscopy including confocal microscopy
&bull All types of electron microscopy
&bull X-ray diffraction
&bull Nuclear magnetic resonance
&bull Scanning force microscopy, scanning probe microscopy, and tunneling microscopy
&bull Digital image processing
&bull Computational insights into structure
The field covered by the journal extends from the structural organization of cells and tissues, their membranes, compartments, organelles and supramolecular assemblies, to the structure and conformation of proteins and nucleic acids from the molecular to the atomic level.
JSB is focused on promoting the authors and the work published in the journal:
Questions were invited online over a 3-month period at http://www.100plantsciencequestions.org.uk/index.php. The website was publicized by email using distribution lists of plant scientists in the UK and abroad, on websites aimed at plant scientists and farmers, and in a press release, which led to coverage by some news websites and newspapers. The questions submitted to the website are listed in full at http://www.100plantsciencequestions.org.uk/viewquestions.php, along with the names of the people who submitted them, apart from a few cases where submitters chose to be anonymous. The online consultation process allowed input from contributors with a range of nationalities and experience. The full list of 350 questions was provided in advance to a panel of 15 individuals (Steve Barnes, Ruth Bastow, Mark Chase, Matthew Clarke, Claire Grierson, Alastair Fitter, Don Grierson, Keith Edwards, Graham Jellis, Jonathan Jones, Sandy Knapp, Giles Oldroyd, Guy Poppy, Paul Temple and Roger Williams) representing the academic, commercial and public service communities that produce or benefit from plant science research, and able to take part in a 2-d workshop at Bristol (UK) in 2009. During the process the list was reduced to 96 questions by mutual agreement, which we hope will stimulate more local variants particularly adapted to research and societal priorities in both the developing and developed world. Before the panel meeting the full list of 350 submitted questions was roughly organized into groups according to topic. Each panel member independently selected their top 20 questions and these lists were combined. During this process other possible questions under each topic were suggested and considered for inclusion. Each question selected by a panel member was discussed by the whole panel, along with other questions that addressed similar issues. The most important question on each topic was agreed upon by the whole panel and a final wording chosen. In some cases the panel decided that a new question was required, and the panel worked together to produce the wordings for these new questions.
The photosynthetic process
The reactions of plant photosynthesis are divided into those that require the presence of sunlight and those that do not. Both types of reactions take place in chloroplasts: light-dependent reactions in the thylakoid and light-independent reactions in the stroma.
Light-dependent reactions (also called light reactions): When a photon of light hits the reaction center, a pigment molecule such as chlorophyll releases an electron.
"The trick to do useful work, is to prevent that electron from finding its way back to its original home," Baum told Live Science. "This is not easily avoided, because the chlorophyll now has an 'electron hole' that tends to pull on nearby electrons."
The released electron manages to escape by traveling through an electron transport chain, which generates the energy needed to produce ATP (adenosine triphosphate, a source of chemical energy for cells) and NADPH. The "electron hole" in the original chlorophyll pigment is filled by taking an electron from water. As a result, oxygen is released into the atmosphere.
Light-independent reactions (also called dark reactions and known as the Calvin cycle): Light reactions produce ATP and NADPH, which are the rich energy sources that drive dark reactions. Three chemical reaction steps make up the Calvin cycle: carbon fixation, reduction and regeneration. These reactions use water and catalysts. The carbon atoms from carbon dioxide are &ldquofixed,&rdquo when they are built into organic molecules that ultimately form three-carbon sugars. These sugars are then used to make glucose or are recycled to initiate the Calvin cycle again.
Virtually all other living creatures depend on plants to survive. Through photosynthesis, plants convert energy from sunlight into food stored as carbohydrates. Because animals cannot get energy directly from the sun, they must eat plants (or other animals that have had a vegetarian meal) to survive. Plants also provide the oxygen humans and animals breathe, because plants use carbon dioxide for photosynthesis and release oxygen into the atmosphere.
Plants are found on land, in oceans, and in fresh water. They have been on Earth for millions of years. Plants were on Earth before animals and currently number about 260,000 species. Three features distinguish plants from animals:
- Plants have chlorophyll, a green pigment necessary for photosynthesis
- Their cell walls are made sturdy by a material called cellulose and
- They are fixed in one place (they don?t move).
In order to study the billions of different organisms living on earth, biologists have sorted and classified them based on their similarities and differences. This system of classification is also called a taxonomy and usually features both English and Latin names for the different divisions.
All plants are included in one so-called kingdom (Kingdom Plantae), which is then broken down into smaller and smaller divisions based on several characteristics, including:
- Whether they can circulate fluids (like rainwater) through their bodies or need to absorb them from the moisture that surrounds them
- How they reproduce (e.g., by spores or different kinds of seeds) and
- Their size or stature.
The majority of the 260,000 plant species are flowering herbs. To describe all plant species, the following divisions (or phyla) are most commonly used to sort them. The first grouping is made up of plants that are non-vascular they cannot circulate rainwater through their stems and leaves but must absorb it from the environment that surrounds them. The remaining plant species are all vascular (they have a system for circulating fluids). This larger group is then split into two groups: one that reproduces from spores rather than seeds, and the other that reproduces from seeds.
Mosses and ?allies,? or related species (Bryophyta and allies)
Mosses or bryophyta are non-vascular. They are an important foundation plant for the forest ecosystem and they help prevent erosion by carpeting the forest floor. All bryophyte species reproduce by spores not seeds, never have flowers, and are found growing on the ground, on rocks, and on other plants.
Originally grouped as a single division or phylum, the 24,000 bryophyte species are now grouped in three divisions: Mosses (Bryophyta), Liverworts (Hepatophyta), and Hornworts (Anthocerotophyta). Also included among the non-vascular plants is Chlorophyta, a kind of fresh-water algae.
Vascular Plants with Spores
Ferns and allies (Pteridophyta and allies)
Unlike mosses, ferns and related species have a vascular system, but like mosses, they reproduce from spores rather than seeds. The ferns are the most plentiful plant division in this group, with 12,000 species. Other divisions (the fern allies) include Club mosses or Lycopods (Lycopodiophyta) with 1,000 species, Horsetails (Equisetophyta) with 40 species, and Whisk ferns (Psilophyta) with 3 species.
Vascular Plants with Seeds
Conifers and allies (Coniferophyta and allies)
Conifers and allies (Coniferophyta and allies) Conifers reproduce from seeds, but unlike plants like blueberry bushes or flowers where the fruit or flower surrounds the seed, conifer seeds (usually cones) are ?naked.? In addition to having cones, conifers are trees or shrubs that never have flowers and that have needle-like leaves. Included among conifers are about 600 species including pines, firs, spruces, cedars, junipers, and yew. The conifer allies include three small divisions with fewer than 200 species all together: Ginko (Ginkophyta) made up of a single species, the maidenhair tree the palm-like Cycads (Cycadophyta), and herb-like plants that bear cones (Gnetophyta) such as Mormon tea.
Flowering Plants (Magnoliophyta)
The vast majority of plants (around 230,000) belong to this category, including most trees, shrubs, vines, flowers, fruits, vegetables, and legumes. Plants in this category are also called angiosperms. They differ from conifers because they grow their seeds inside an ovary, which is embedded in a flower or fruit.