South America is a continent in the Western Hemisphere in the Southern Hemisphere, with a small portion in the Northern Hemisphere. It may be considered a subcontinent of the Americas, how it is viewed in the Spanish and Portuguese-speaking regions of the Americas; the reference to South America instead of other regions has increased in the last decades due to changing geopolitical dynamics. It is bordered on the west on the north and east by the Atlantic Ocean, it includes twelve sovereign states, a part of France, a non-sovereign area. In addition to this, the ABC islands of the Kingdom of the Netherlands and Tobago, Panama may be considered part of South America. South America has an area of 17,840,000 square kilometers, its population as of 2016 has been estimated at more than 420 million. South America ranks fourth in fifth in population. Brazil is by far the most populous South American country, with more than half of the continent's population, followed by Colombia, Argentina and Peru. In recent decades Brazil has concentrated half of the region's GDP and has become a first regional power.
Most of the population lives near the continent's western or eastern coasts while the interior and the far south are sparsely populated. The geography of western South America is dominated by the Andes mountains. Most of the continent lies in the tropics; the continent's cultural and ethnic outlook has its origin with the interaction of indigenous peoples with European conquerors and immigrants and, more locally, with African slaves. Given a long history of colonialism, the overwhelming majority of South Americans speak Portuguese or Spanish, societies and states reflect Western traditions. South America occupies the southern portion of the Americas; the continent is delimited on the northwest by the Darién watershed along the Colombia–Panama border, although some may consider the border instead to be the Panama Canal. Geopolitically and geographically all of Panama – including the segment east of the Panama Canal in the isthmus – is included in North America alone and among the countries of Central America.
All of mainland South America sits on the South American Plate. South America is home to Angel Falls in Venezuela. South America's major mineral resources are gold, copper, iron ore and petroleum; these resources found in South America have brought high income to its countries in times of war or of rapid economic growth by industrialized countries elsewhere. However, the concentration in producing one major export commodity has hindered the development of diversified economies; the fluctuation in the price of commodities in the international markets has led to major highs and lows in the economies of South American states causing extreme political instability. This is leading to efforts to diversify production to drive away from staying as economies dedicated to one major export. South America is one of the most biodiverse continents on earth. South America is home to many interesting and unique species of animals including the llama, piranha, vicuña, tapir; the Amazon rainforests possess high biodiversity, containing a major proportion of the Earth's species.
Brazil is the largest country in South America, encompassing around half of the continent's land area and population. The remaining countries and territories are divided among three regions: The Andean States, the Guianas and the Southern Cone. Traditionally, South America includes some of the nearby islands. Aruba, Curaçao, Trinidad and the federal dependencies of Venezuela sit on the northerly South American continental shelf and are considered part of the continent. Geo-politically, the island states and overseas territories of the Caribbean are grouped as a part or subregion of North America, since they are more distant on the Caribbean Plate though San Andres and Providencia are politically part of Colombia and Aves Island is controlled by Venezuela. Other islands that are included with South America are the Galápagos Islands that belong to Ecuador and Easter Island, Robinson Crusoe Island, Chiloé and Tierra del Fuego. In the Atlantic, Brazil owns Fernando de Noronha and Martim Vaz, the Saint Peter and Saint Paul Archipelago, while the Falkland Islands are governed by the United Kingdom, whose sovereignty over the islands is disputed by Argentina.
South Georgia and the South Sandwich Islands may be associate
The eudicots, Eudicotidae or eudicotyledons are a clade of flowering plants, called tricolpates or non-magnoliid dicots by previous authors. The botanical terms were introduced in 1991 by evolutionary botanist James A. Doyle and paleobotanist Carol L. Hotton to emphasize the evolutionary divergence of tricolpate dicots from earlier, less specialized, dicots; the close relationships among flowering plants with tricolpate pollen grains was seen in morphological studies of shared derived characters. These plants have a distinct trait in their pollen grains of exhibiting three colpi or grooves paralleling the polar axis. Molecular evidence confirmed the genetic basis for the evolutionary relationships among flowering plants with tricolpate pollen grains and dicotyledonous traits; the term means "true dicotyledons", as it contains the majority of plants that have been considered dicots and have characteristics of the dicots. The term "eudicots" has subsequently been adopted in botany to refer to one of the two largest clades of angiosperms, monocots being the other.
The remaining angiosperms include magnoliids and what are sometimes referred to as basal angiosperms or paleodicots, but these terms have not been or adopted, as they do not refer to a monophyletic group. The other name for the eudicots is tricolpates, a name which refers to the grooved structure of the pollen. Members of the group have tricolpate pollen; these pollens have three or more pores set in furrows called colpi. In contrast, most of the other seed plants produce monosulcate pollen, with a single pore set in a differently oriented groove called the sulcus; the name "tricolpates" is preferred by some botanists to avoid confusion with the dicots, a nonmonophyletic group. Numerous familiar plants are eudicots, including many common food plants and ornamentals; some common and familiar eudicots include members of the sunflower family such as the common dandelion, the forget-me-not and other members of its family, buttercup and macadamia. Most leafy trees of midlatitudes belong to eudicots, with notable exceptions being magnolias and tulip trees which belong to magnoliids, Ginkgo biloba, not an angiosperm.
The name "eudicots" is used in the APG system, of 1998, APG II system, of 2003, for classification of angiosperms. It is applied to a monophyletic group, which includes most of the dicots. "Tricolpate" is a synonym for the "Eudicot" monophyletic group, the "true dicotyledons". The number of pollen grain furrows or pores helps classify the flowering plants, with eudicots having three colpi, other groups having one sulcus. Pollen apertures are any modification of the wall of the pollen grain; these modifications include thinning and pores, they serve as an exit for the pollen contents and allow shrinking and swelling of the grain caused by changes in moisture content. The elongated apertures/ furrows in the pollen grain are called colpi, along with pores, are a chief criterion for identifying the pollen classes; the eudicots can be divided into two groups: the basal eudicots and the core eudicots. Basal eudicot is an informal name for a paraphyletic group; the core eudicots are a monophyletic group.
A 2010 study suggested the core eudicots can be divided into two clades, Gunnerales and a clade called "Pentapetalae", comprising all the remaining core eudicots. The Pentapetalae can be divided into three clades: Dilleniales superrosids consisting of Saxifragales and rosids superasterids consisting of Santalales, Berberidopsidales and asteridsThis division of the eudicots is shown in the following cladogram: The following is a more detailed breakdown according to APG IV, showing within each clade and orders: clade Eudicots order Ranunculales order Proteales order Trochodendrales order Buxales clade Core eudicots order Gunnerales order Dilleniales clade Superrosids order Saxifragales clade Rosids order Vitales clade Fabids order Fabales order Rosales order Fagales order Cucurbitales order Oxalidales order Malpighiales order Celastrales order Zygophyllales clade Malvids order Geraniales order Myrtales order Crossosomatales order Picramniales order Malvales order Brassicales order Huerteales order Sapindales clade Superasterids order Berberidopsidales order Santalales order Caryophyllales clade Asterids order Cornales order Ericales clade Campanulids order Aquifoliales order Asterales order Escalloniales order Bruniales order Apiales order Dipsacales order Paracryphiales clade Lamiids order Solanales order Lamiales order Vahliales order Gentianales order Boraginales order Garryales order Metteniusales order Icacinales Eudicots at the Encyclopedia of Life Eudicots, Tree of Life Web Project Dicots Plant Life Forms
Mikania natalensis, the Natal Mikania, is a plant in the Asteraceae family, is native to Africa. It is found on forest margins from the Eastern Cape of South Africa to Tropical Africa. Mikania natalensis is a vigorous perennial climber; the leaves are well spaced. The leaf stalk is up to 30 mm long; the leaf blade is about 80 mm by 40 mm, long-pointed, with pointed backward extensions. The leaf margin is toothed. There are five veins in the leaf from the base; the leaves are velvety grey beneath, thinly pubescent above. Flowers are 10 mm long, cream-coloured with purplish anthers and white corollas; the flowers are scented and produced from April through September. Mikania natalensis is superficially similar in appearance to Chromolaena odorata, an alien invader species in the natural habitat of Mikania natalensis; the butterfly Actinote thalia was considered for the biological control of Chromolaena odorata in southern Africa, but permission to release this control agent was not sought because the larvae were found to consume the leaves of Mikania natalensis.
Mikania natalensis is used in traditional Zulu and Swazi medicine for urinary complaints, headaches and colds. The flowers are visited by butterflies, bees and flies
Guaco, huaco, or guao vejuco and bejuco are terms applied to various vine-like Central American, South American, West Indian climbing plants, reputed to have curative powers. Several species in the genus Mikania are among those referred to as guaco. Though it is not a vine guaco is used to refer to Cleome serrulata, the Rocky Mountain beeplant. Native Americans and Colombians believe that the guaco was named after a species of kite, in imitation of its cry, which they say it uses to attract the snakes which it feeds on. Tradition says that the plant's powers as an antidote were discovered through watching the bird eat the leaves, spread the juice on its wings, before attacking the snakes. Any twining plant with a heart-shaped leaf and green above and purple beneath, is called a guaco by Native Americans, which does not coincide with which plants are “true” guacos, as far as naturalists are concerned. What is most recognized in Colombia as guaco, or vejuco del guaco, would appear to be Mikania guaco, a climbing composite plant of the tribe Eupatorieae, preferring moist and shady situations, having a much-branched and deep-growing root, serrated, opposite leaves and dull white flowers, in axillary clusters.
The whole plant emits a disagreeable odour. It is stated that the Central American natives, after taking guaco, catch with impunity the most dangerous snakes, which writhe in their hands as though touched by a hot iron; the odour alone of guaco, has been said to cause, in a state of stupor. The drug is not used in modern medicine. In Brazil, guaco is used as a medicinal tea as an expectorant and anti-inflammatory due to its compound cumarine; the plant is sold in pharmacies. This article incorporates text from a publication now in the public domain: Chisholm, Hugh, ed.. "Guaco". Encyclopædia Britannica. Cambridge University Press
A liana is any of various long-stemmed, woody vines that are rooted in the soil at ground level and use trees, as well as other means of vertical support, to climb up to the canopy to get access to well-lit areas of the forest. Lianas are characteristic of tropical moist deciduous forests, but may be found in temperate rainforests. There are temperate lianas, for example the members of the Clematis or Vitis genera. Lianas can form bridges amidst the forest canopy, providing arboreal animals with paths across the forest; these bridges can protect weaker trees from strong winds. Lianas compete with forest trees for sunlight and nutrients from the soil. Forests without lianas grow 150% more fruit; the term "liana" is not a taxonomic grouping, but rather a description of the way the plant grows – much like "tree" or "shrub". Lianas may be found in many different plant families. One way of distinguishing lianas from trees and shrubs is based on the stiffness the Young's modulus of various parts of the stem.
Trees and shrubs have young twigs and smaller branches which are quite flexible and older growth such as trunks and large branches which are stiffer. A liana has stiff young growths and older, more flexible growth at the base of the stem. Described genera containing liana species include: Gnetophyta Gnetum spp. Acanthaceae Mendoncia spp. Thunbergia spp. e.g. T. grandiflora, T. mysorensisAncistrocladaceae Ancistrocladus spp. Annonaceae Artabotrys spp. Fissistigma spp. Uvaria spp. Apocynaceae Odontadenia spp. Strophanthus – several spp. including S. sarmentosusArecaceae Calamoideae – rattans: several genera including: Calamus spp. Daemonorops spp. Araceae Pothos spp. Aristolochiaceae Aristolochia spp. Bignoniaceae Anemopaegma spp. Capparaceae Capparis spp. Connaraceae Connarus spp. Dilleniaceae Doliocarpus spp. Dioscoreaceae Dioscorea spp.: the yam family Fabaceae: not leguminous vines are well represented: – Caesalpinioideae Acacia some spp.: e.g. A. concinna "cat's claw" lianas including: Hultholia mimosoides Mezoneuron spp.
Entada spp. Pterolobium spp.– Cercidoideae Lasiobema and Phanera spp.: "monkey ladders" or "snake climbers"– Faboideae Dalbergia armata: of subtropical Africa Derris spp. Machaerium spp. Mucuna spp. Strongylodon spp. Flagellariaceae Flagellaria indicaLoganiaceae Strychnos spp. e.g. S. axillarisNepenthaceae Nepenthes spp. Oleaceae Jasminum spp. Polygalaceae Moutabea: M. aculeataSapindaceae Paullinia spp. Rhamnaceae Ventilago spp. Ziziphus spp. Rubiaceae Uncaria spp. Rutaceae Toddalia asiaticaSchlegeliaceae Schlegelia spp. Smilacaceae Smilax spp. Vitaceae Ampelopsis spp. Cissus spp. "water vines" Parthenocissus spp. Tetrastigma spp. Vitis spp. Lianas compete intensely with trees reducing tree growth and tree reproduction increasing tree mortality, preventing tree seedlings from establishing, altering the course of regeneration in forests, affecting tree population growth rates. Lianas provide access routes in the forest canopy for many arboreal animals, including ants and many other invertebrates, rodents, sloths and lemurs.
For example, in the Eastern tropical forests of Madagascar, many lemurs achieve higher mobility from the web of lianas draped amongst the vertical tree species. Many lemurs prefer trees with lianas for their roost sites. Lianas provide support for trees when strong winds blow. However, they may be destructive in that when one tree falls, the connections made by the lianas may cause many other trees to fall; as noted by Charles Darwin, because lianas are supported by other plants, they may conserve resources that other plants must allocate to the development of structure and use them instead for growth and reproduction. In general, lianas are detrimental to the trees. Growth rates are lower for trees with lianas. Lianas make the canopy of trees more accessible to animals which eat leaves; because of these negative effects, trees which remain free of lianas are at an advantage. The New Student's Reference Work. 1914
Carl Ludwig Willdenow
Carl Ludwig Willdenow was a German botanist and plant taxonomist. He is considered one of the founders of phytogeography, the study of the geographic distribution of plants. Willdenow was a mentor of Alexander von Humboldt, one of the earliest and best known phytogeographers, he influenced Christian Konrad Sprengel, who pioneered the study of plant pollination and floral biology. Willdenow was studied medicine and botany at the University of Halle. After studying pharmaceutics at Wieglieb College, Langensalza and in medicine at Halle, he returned to Berlin to work at his father's pharmacy located in the Unter den Linden, his early interest in botany was kindled by his uncle J. G. Gleditsch and he started a herbarium collection in his teenage years. In 1794 he became a member of the Berlin Academy of Sciences, he was a director of the Botanical garden of Berlin from 1801 until his death. In 1807 Alexander von Humboldt helped to expand the garden. There he studied many South American plants, brought back by Humboldt.
He was interested in the adaptation of plants to climate, showing that the same climate had plants having common characteristics. His herbarium, containing more than 20,000 species, is still preserved in the Botanical Garden in Berlin; some of the specimens include those collected by Humboldt. Humboldt notes that as a young man he was unable to identify plants using Willdenow's Flora Berolinensis, he subsequently visited Willdenow without an appointment and found him to be a kindred soul only four years older and in three weeks he became an enthusiastic botanist. In his 1792 book, Grundriss der Kräuterkunde or Geschichte der Pflanzen Willdenow came up with an idea to explain restricted plant distributions. Willdenow suggested that it was based on past history with mountains surrounded by seas with different sets of plants restricted to the peaks which spread downward and out with receding sea levels; this would fit with the Biblical notion of floods. This was contrary to earlier assertions by Eberhard August Wilhelm von Zimmermann that plants were distributed as they had been in the past and that there had been no changes.
Florae Berolinensis prodromus Grundriß der Kräuterkunde Linnaei species plantarum Botanicus Anleitung zum Selbststudium der Botanik Historia Amaranthorum Phytographia Enumeratio plantarum horti regii botanici Berolinensis Berlinische Baumzucht Abbildung der deutschen Holzarten für Forstmänner und Liebhaber der Botanik Digital edition by the University and State Library Düsseldorf Hortus Berolinensis Grundriss der Kräuterkunde zu Vorlesungen Allgemeine Deutsche Biographie
Mexico the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States. Covering 2,000,000 square kilometres, the nation is the fifth largest country in the Americas by total area and the 13th largest independent state in the world. With an estimated population of over 120 million people, the country is the eleventh most populous state and the most populous Spanish-speaking state in the world, while being the second most populous nation in Latin America after Brazil. Mexico is a federation comprising 31 states and Mexico City, a special federal entity, the capital city and its most populous city. Other metropolises in the state include Guadalajara, Puebla, Tijuana and León. Pre-Columbian Mexico dates to about 8000 BC and is identified as one of five cradles of civilization and was home to many advanced Mesoamerican civilizations such as the Olmec, Teotihuacan, Zapotec and Aztec before first contact with Europeans. In 1521, the Spanish Empire conquered and colonized the territory from its politically powerful base in Mexico-Tenochtitlan, administered as the viceroyalty of New Spain.
Three centuries the territory became a nation state following its recognition in 1821 after the Mexican War of Independence. The post-independence period was tumultuous, characterized by economic inequality and many contrasting political changes; the Mexican–American War led to a territorial cession of the extant northern territories to the United States. The Pastry War, the Franco-Mexican War, a civil war, two empires, the Porfiriato occurred in the 19th century; the Porfiriato was ended by the start of the Mexican Revolution in 1910, which culminated with the promulgation of the 1917 Constitution and the emergence of the country's current political system as a federal, democratic republic. Mexico has the 11th largest by purchasing power parity; the Mexican economy is linked to those of its 1994 North American Free Trade Agreement partners the United States. In 1994, Mexico became the first Latin American member of the Organisation for Economic Co-operation and Development, it is classified as an upper-middle income country by the World Bank and a newly industrialized country by several analysts.
The country is considered both a regional power and a middle power, is identified as an emerging global power. Due to its rich culture and history, Mexico ranks first in the Americas and seventh in the world for number of UNESCO World Heritage Sites. Mexico is an ecologically megadiverse country, ranking fourth in the world for its biodiversity. Mexico receives a huge number of tourists every year: in 2018, it was the sixth most-visited country in the world, with 39 million international arrivals. Mexico is a member of the United Nations, the World Trade Organization, the G8+5, the G20, the Uniting for Consensus group of the UN, the Pacific Alliance trade bloc. Mēxihco is the Nahuatl term for the heartland of the Aztec Empire, namely the Valley of Mexico and surrounding territories, with its people being known as the Mexica, it is believed to be a toponym for the valley which became the primary ethnonym for the Aztec Triple Alliance as a result, although it could have been the other way around.
In the colonial era, back when Mexico was called New Spain this territory became the Intendency of Mexico and after New Spain achieved independence from the Spanish Empire it came to be known as the State of Mexico with the new country being named after its capital: the City of Mexico, which itself was founded in 1524 on top of the ancient Mexica capital of Mexico-Tenochtitlan. Traditionally, the name Tenochtitlan was thought to come from Nahuatl tetl and nōchtli and is thought to mean "Among the prickly pears rocks". However, one attestation in the late 16th-century manuscript known as "the Bancroft dialogues" suggests the second vowel was short, so that the true etymology remains uncertain; the suffix -co is the Nahuatl locative, making the word a place name. Beyond that, the etymology is uncertain, it has been suggested that it is derived from Mextli or Mēxihtli, a secret name for the god of war and patron of the Mexica, Huitzilopochtli, in which case Mēxihco means "place where Huitzilopochtli lives".
Another hypothesis suggests that Mēxihco derives from a portmanteau of the Nahuatl words for "moon" and navel. This meaning might refer to Tenochtitlan's position in the middle of Lake Texcoco; the system of interconnected lakes, of which Texcoco formed the center, had the form of a rabbit, which the Mesoamericans pareidolically associated with the moon rabbit. Still another hypothesis suggests that the word is derived from Mēctli, the name of the goddess of maguey; the name of the city-state was transliterated to Spanish as México with the phonetic value of the letter x in Medieval Spanish, which represented the voiceless postalveolar fricative. This sound, as well as the voiced postalveolar fricative, represented by a j, evolved into a voiceless velar fricative during the 16th century; this led to the use of the variant Méjico in many publications in Spanish, most notably in Spain, whereas in Mexico and most other Spanish–speaking countries, México was the preferred spelling. In recent years, the Real Academia Española, which regulates the Spanish l