A river mouth is the part of a river where the river debouches into another river, a lake, a reservoir, a sea, or an ocean. The water from a river can enter the receiving body in a variety of different ways; the motion of a river is influenced by the relative density of the river compared to the receiving water, the rotation of the earth, any ambient motion in the receiving water, such as tides or seiches. If the river water has a higher density than the surface of the receiving water, the river water will plunge below the surface; the river water will either form an underflow or an interflow within the lake. However, if the river water is lighter than the receiving water, as is the case when fresh river water flows into the sea, the river water will float along the surface of the receiving water as an overflow. Alongside these advective transports, inflowing water will diffuse. At the mouth of a river, the change in flow condition can cause the river to drop any sediment it is carrying; this sediment deposition can generate a variety of landforms, such as deltas, sand bars and tie channels.
Many places in the United Kingdom take their names from their positions at the mouths of rivers, such as Plymouth and Great Yarmouth. Confluence River delta Estuary Liman
A fossil is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, petrified wood, coal, DNA remnants; the totality of fossils is known as the fossil record. Paleontology is the study of fossils: their age, method of formation, evolutionary significance. Specimens are considered to be fossils if they are over 10,000 years old; the oldest fossils are around 3.48 billion years old to 4.1 billion years old. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils; the development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the absolute ages of rocks and the fossils they host. There are many processes that lead to fossilization, including permineralization and molds, authigenic mineralization and recrystallization, adpression and bioimmuration.
Fossils vary in size from one-micrometre bacteria to dinosaurs and trees, many meters long and weighing many tons. A fossil preserves only a portion of the deceased organism that portion, mineralized during life, such as the bones and teeth of vertebrates, or the chitinous or calcareous exoskeletons of invertebrates. Fossils may consist of the marks left behind by the organism while it was alive, such as animal tracks or feces; these types of fossil are called trace ichnofossils, as opposed to body fossils. Some fossils are called chemofossils or biosignatures; the process of fossilization varies according to external conditions. Permineralization is a process of fossilization; the empty spaces within an organism become filled with mineral-rich groundwater. Minerals precipitate from the groundwater; this process can occur in small spaces, such as within the cell wall of a plant cell. Small scale permineralization can produce detailed fossils. For permineralization to occur, the organism must become covered by sediment soon after death, otherwise decay commences.
The degree to which the remains are decayed when covered determines the details of the fossil. Some fossils consist only of skeletal teeth; this is a form of diagenesis. In some cases, the original remains of the organism dissolve or are otherwise destroyed; the remaining organism-shaped hole in the rock is called an external mold. If this hole is filled with other minerals, it is a cast. An endocast, or internal mold, is formed when sediments or minerals fill the internal cavity of an organism, such as the inside of a bivalve or snail or the hollow of a skull; this is a special form of mold formation. If the chemistry is right, the organism can act as a nucleus for the precipitation of minerals such as siderite, resulting in a nodule forming around it. If this happens before significant decay to the organic tissue fine three-dimensional morphological detail can be preserved. Nodules from the Carboniferous Mazon Creek fossil beds of Illinois, USA, are among the best documented examples of such mineralization.
Replacement occurs. In some cases mineral replacement of the original shell occurs so and at such fine scales that microstructural features are preserved despite the total loss of original material. A shell is said to be recrystallized when the original skeletal compounds are still present but in a different crystal form, as from aragonite to calcite. Compression fossils, such as those of fossil ferns, are the result of chemical reduction of the complex organic molecules composing the organism's tissues. In this case the fossil consists of original material, albeit in a geochemically altered state; this chemical change is an expression of diagenesis. What remains is a carbonaceous film known as a phytoleim, in which case the fossil is known as a compression. However, the phytoleim is lost and all that remains is an impression of the organism in the rock—an impression fossil. In many cases, however and impressions occur together. For instance, when the rock is broken open, the phytoleim will be attached to one part, whereas the counterpart will just be an impression.
For this reason, one term covers the two modes of preservation: adpression. Because of their antiquity, an unexpected exception to the alteration of an organism's tissues by chemical reduction of the complex organic molecules during fossilization has been the discovery of soft tissue in dinosaur fossils, including blood vessels, the isolation of proteins and evidence for DNA fragments. In 2014, Mary Schweitzer and her colleagues reported the presence of iron particles associated with soft tissues recovered from dinosaur fossils. Based on various experiments that studied the interaction of iron in haemoglobin with blood vessel tissue they proposed that solution hypoxia coupled with iron chelation enhances the stability and preservation of soft tissue and provides the basis for an explanation for the unforeseen preservation of fossil soft tissues. However, a older study based on eight taxa ranging in time from the Devonian to the Jurassic found that reasonably well-preserved fibrils that represent collagen were preser
East London, Eastern Cape
East London is a city on the southeast coast of South Africa in the Buffalo City Metropolitan Municipality of the Eastern Cape province. The city lies on the Indian Ocean coast between the Buffalo River and the Nahoon River, hosts the country's only river port; as of 2011, East London had a population of over 267,000 with over 755,000 in the metropolitan area. John Bailie, one of the 1820 Settlers, surveyed the Buffalo River mouth and founded the town in 1836, a memorial on Signal Hill commemorating the event; the city formed around the only river port in South Africa and was known as Port Rex. It was renamed London in honour of the capital city of Great Britain, hence the name East London; this settlement on the West Bank was the nucleus of the town of East London, elevated to city status in 1914. During the early to mid-19th century frontier wars between the British settlers and the local Xhosa inhabitants, East London served as a supply port to service the military headquarters at nearby King William's Town, about 50 kilometres away.
A British fort, Fort Glamorgan, was built on the West Bank in 1847, annexed to the Cape Colony that same year. This fort is one of a series of British-built forts, including Fort Murray, Fort White, Fort Cox, Fort Hare,Fort Jackson and Fort Beaufort, in the border area that became known as British Kaffraria. With development of the port came the settlement of permanent residents, including German settlers, most of whom were bachelors; these settlers were responsible for German names of some towns in the vicinity of East London such as Stutterheim and Berlin. Today, German surnames such as Gehring and Peinke are still common in East London, but the descendants of the settlers became Anglicised; the existing port, in the mouth of the Buffalo River, adjoining the Indian Ocean, began operating in 1870. In 1872, the Cape Colony, under the leadership of its first Prime Minister John Molteno, attained a degree of independence from Britain; the new government merged the three neighbouring settlements of East London, East London East and Panmure in 1873, forming the core of the current municipality, in 1876 it began construction on the region's railway lines, commencing on the river's east bank.
At the same time, it began construction of the East London harbour. This new infrastructure accelerated development of the area, into today's thriving city of East London; the unusual double-decker bridge over the Buffalo River was completed in 1935, to this day, is the only bridge of its type in South Africa. Modern day attractions include the Gately House, City Hall, Cape Railways, Nahoon Museum, East London Museum housing the coelacanth, a prehistoric fish, thought to be extinct, discovered live at the Chalumna River mouth near East London by fishermen in 1938, numerous memorial statues. In 1948 the National Party came to power in South Africa, began to implement the policy of apartheid. Apartheid as a doctrine envisaged the total segregation of races in South Africa, East London was not any different. In 1950, the Group Areas Act was placed upon the statute books making absolute segregation in all urban areas mandatory. In 1951, the Land Tenure Advisory Board, the body created to enforce the act, conducted initial investigations into the reallocation of space along racial lines in East London.
Residential segregration had long been practiced in East London prior to the advent of apartheid. In 1941, the East London Municipality moved residents from East Bank townships to the newly built township of Duncan Village. In 1951, all inter-racial property exchanges were prohibited in East London. In 1955, the Amalinda area was zoned as a White Group Area by Government Gazette Proclamation number 21; this meant that the municipality's plans to extend the area in order to accommodate the black African population were abandoned. In 1953, residents in the East Bank were forcibly moved to the new township of Mdantsane. In February 1966, the apartheid South African government defined Mdantsane as a separate homeland township. In 1956, South African President Henrik Verwoerd, the archarchitect of apartheid, forbade the East London municipality from extending the existing Duncan Village township and sanctioned the building of Mdantsane. In 1961, these plans provided for the allocation of a distinct wedge of the city for Asian and Coloured residence, which "incorporated the areas of North End and the proclaimed Buffalo Flats location.
This plan occasioned tremendous resentment in the city prompting petitions and letters of complaint from numerous organisations including the Black Sash, trade unions and various black community groups. In 1967, the East London Municipality proclaimed the majority of the city an area for white occupancy, with the exception of a broad sector of land encompassing the Parkside and Buffalo Flats areas, zoned for coloured residence. Certain parts of Duncan Village were disestablished and its African residents removed, new coloured and Asian locations were built and proclaimed upon land in 1973. In the same year, the newly-constructed location of Braelynn was proclaimed an Indian area while Buffalo Flats Extension and Pefferville were proclaimed as coloured areas; the construction/ extension of coloured areas and the Duncan Village were suspended in 1983. At the end of apartheid in 1994, East London became part of the province of Eastern Cape. In 2000, East London became part of Buffalo City Metropolitan Municipality consisting of King William's Town and Mdantsane and is the seat of the Metro.
East London is the second largest industrial centre in the province. The motor industry is the dominant employer. A major Daimler plant is located next to the harbour, manufacturing Mercedes-Benz and other vehicles for the
South Africa the Republic of South Africa, is the southernmost country in Africa. It is bounded to the south by 2,798 kilometres of coastline of Southern Africa stretching along the South Atlantic and Indian Oceans. South Africa is the largest country in Southern Africa and the 25th-largest country in the world by land area and, with over 57 million people, is the world's 24th-most populous nation, it is the southernmost country on the mainland of the Eastern Hemisphere. About 80 percent of South Africans are of Sub-Saharan African ancestry, divided among a variety of ethnic groups speaking different African languages, nine of which have official status; the remaining population consists of Africa's largest communities of European and multiracial ancestry. South Africa is a multiethnic society encompassing a wide variety of cultures and religions, its pluralistic makeup is reflected in the constitution's recognition of 11 official languages, the fourth highest number in the world. Two of these languages are of European origin: Afrikaans developed from Dutch and serves as the first language of most coloured and white South Africans.
The country is one of the few in Africa never to have had a coup d'état, regular elections have been held for a century. However, the vast majority of black South Africans were not enfranchised until 1994. During the 20th century, the black majority sought to recover its rights from the dominant white minority, with this struggle playing a large role in the country's recent history and politics; the National Party imposed apartheid in 1948. After a long and sometimes violent struggle by the African National Congress and other anti-apartheid activists both inside and outside the country, the repeal of discriminatory laws began in 1990. Since 1994, all ethnic and linguistic groups have held political representation in the country's liberal democracy, which comprises a parliamentary republic and nine provinces. South Africa is referred to as the "rainbow nation" to describe the country's multicultural diversity in the wake of apartheid; the World Bank classifies South Africa as an upper-middle-income economy, a newly industrialised country.
Its economy is the second-largest in Africa, the 34th-largest in the world. In terms of purchasing power parity, South Africa has the seventh-highest per capita income in Africa; however and inequality remain widespread, with about a quarter of the population unemployed and living on less than US$1.25 a day. South Africa has been identified as a middle power in international affairs, maintains significant regional influence; the name "South Africa" is derived from the country's geographic location at the southern tip of Africa. Upon formation, the country was named the Union of South Africa in English, reflecting its origin from the unification of four separate British colonies. Since 1961, the long form name in English has been the "Republic of South Africa". In Dutch, the country was named Republiek van Zuid-Afrika, replaced in 1983 by the Afrikaans Republiek van Suid-Afrika. Since 1994, the Republic has had an official name in each of its 11 official languages. Mzansi, derived from the Xhosa noun umzantsi meaning "south", is a colloquial name for South Africa, while some Pan-Africanist political parties prefer the term "Azania".
South Africa contains human-fossil sites in the world. Archaeologists have recovered extensive fossil remains from a series of caves in Gauteng Province; the area, a UNESCO World Heritage site, has been branded "the Cradle of Humankind". The sites include one of the richest sites for hominin fossils in the world. Other sites include Gondolin Cave Kromdraai, Coopers Cave and Malapa. Raymond Dart identified the first hominin fossil discovered in Africa, the Taung Child in 1924. Further hominin remains have come from the sites of Makapansgat in Limpopo Province and Florisbad in the Free State Province, Border Cave in KwaZulu-Natal Province, Klasies River Mouth in Eastern Cape Province and Pinnacle Point and Die Kelders Cave in Western Cape Province; these finds suggest that various hominid species existed in South Africa from about three million years ago, starting with Australopithecus africanus. There followed species including Australopithecus sediba, Homo ergaster, Homo erectus, Homo rhodesiensis, Homo helmei, Homo naledi and modern humans.
Modern humans have inhabited Southern Africa for at least 170,000 years. Various researchers have located pebble tools within the Vaal River valley. Settlements of Bantu-speaking peoples, who were iron-using agriculturists and herdsmen, were present south of the Limpopo River by the 4th or 5th century CE, they displaced and absorbed the original Khoisan speakers, the Khoikhoi and San peoples. The Bantu moved south; the earliest ironworks in modern-day KwaZulu-Natal Province are believed to date from around 1050. The southernmost group was the Xhosa people, whose language incorporates certain linguistic traits from the earlier Khoisan people; the Xhosa reached the Great Fish River, in today's Eastern Cape Province. As they migrated, these larger Iron Age populations
Provinces of South Africa
South Africa is divided into nine provinces. On the eve of the 1994 general election, South Africa's former homelands known as Bantustans, were reintegrated and the four existing provinces were divided into nine; the twelfth and sixteenth amendments to the constitution changed the borders of seven of the provinces. The Union of South Africa was established in 1910 by combining four British colonies: the Cape Colony, the Natal Colony, the Transvaal Colony and the Orange River Colony; these colonies became the four original provinces of the Union: Cape Province, Transvaal Province, Natal Province and Orange Free State Province. Segregation of the black population started as early as 1913, with ownership of land by the black majority being restricted to certain areas totalling about 13% of the country. From the late 1950s, these areas were consolidated into "homelands" called "bantustans". Four of these homelands were established as quasi-independent nation states of the black population during the apartheid era.
In 1976, the homeland of Transkei was the first to accept independence from South Africa, although this independence was never acknowledged by any other country, three other homelands – Bophuthatswana and Ciskei – followed suit. On 27 April 1994, the date of the first non-racial elections and of the adoption of the Interim Constitution, all of these provinces and homelands were dissolved, nine new provinces were established; the boundaries of these provinces were established in 1993 by a Commission on the Demarcation/Delimitation of Regions created by CODESA, were broadly based on planning regions demarcated by the Development Bank of Southern Africa in the 1980s, amalgamated from existing magisterial districts, with some concessions to political parties that wished to consolidate their power bases, by transferring districts between the proposed provinces. South Africa’s provinces are governed, in different ways, on a national and local level. Nationally, there is the National Council of one of the houses of Parliament.
There is the provincial government and, below that, the administration of district and metropolitan municipalities. South Africa has two houses of parliament: the National Assembly, the National Council of Provinces; the second exists to ensure that the interests of each province are protected in the laws passed by the National Assembly. Each one of South Africa’s nine provinces sends 10 representatives to the National Council of Provinces. Six of these are permanent members of the council, four are special delegates; each province is governed by a unicameral legislature. The size of the legislature is proportional to population, ranging from 30 members in the Northern Cape to 80 in KwaZulu-Natal; the legislatures are elected every five years by a system of party-list proportional representation. The provincial legislature elects, from amongst its members, a Premier, the head of the executive; the Premier chooses an Executive Council consisting of between five and ten members of the legislature, the cabinet of the provincial government.
The Members of the Executive Council are the provincial equivalent of ministers. The powers of the provincial government are limited to specific topics listed in the national constitution. On some of these topics – for example, education and public housing – the province's powers are shared with the national government, which can establish uniform standards and frameworks for the provincial governments to follow; the provinces do not have their own court systems, as the administration of justice is the responsibility of the national government. Footnotes: † These statistics do not include the Prince Edward Islands, which are South African territories in the sub-Antarctic Indian Ocean but part of the Western Cape for legal and electoral purposes. ‡ Pietermaritzburg and Ulundi were joint capitals of KwaZulu-Natal from 1994 to 2004. Footnotes: † States for which the homeland was quasi-independent. Elections in South Africa Prince Edward Islands Proposals for South Africa to annex Lesotho Walvis Bay ISO 3166-2:ZA
Marjorie Eileen Doris Courtenay-Latimer was the South African museum official who in 1938 brought to the attention of the world the existence of the coelacanth, a fish thought to have been extinct for sixty-five million years. Courtenay-Latimer was born in East London, South Africa, the daughter of a stationmaster for South African Railways, she was born two months prematurely and throughout her childhood she was a sickly child, nearly dying on one occasion due to a diphtheria infection. Despite her frailty, from a young age she enjoyed outdoor activities; when she visited her grandmother on the coast, she was fascinated by the lighthouse on Bird Island. At age eleven, she vowed. After school, she trained to become a nurse at King William's Town but, just before finishing her training, she was alerted to a job opening at the opened East London Museum, East London, Eastern Cape. Although never having received any formal training, she impressed her interviewers with her range of South African naturalistic knowledge and was hired at the age of twenty-four, August 1931.
Courtenay-Latimer spent the rest of her career at the museum, retiring first to a farm at Tsitsikamma where she wrote a book on flowers and back to East London. She never married due to the ″love of her life″ dying in her twenties, she busily worked on collecting rocks, feathers and the like for her museum, made her desire to see unusual specimens known to fishermen. On 22 December 1938, she received, she went to the docks to inspect the catch of Captain Hendrik Goosen. "I picked away at the layers of slime to reveal the most beautiful fish I had seen," she said. "It was five feet long, a pale mauvy blue with faint flecks of whitish spots. It was covered in hard scales, it had four limb-like fins and a strange puppy dog tail." She tried to find it in her books without success. Eager to preserve the fish and, having no facilities at the museum, Courtenay-Latimer took it to the morgue, which refused to assist her, she tried to contact J. L. B. Smith, a friend who taught at Rhodes University, to help her identify it.
Courtenay-Latimer reluctantly gut it. When Smith arrived on 16 February 1939, he recognized the fish as a coelacanth. "There was not a shadow of a doubt", he said. "It could have been one of those creatures of 200 million years ago come alive again". Smith would give it the scientific name Latimeria chalumnae after his friend and the Chalumna River, where it was found, it would be fourteen more years. Gray's Mesoplodon Grayi. Annals of the Cape Provincial Museums Vol.3 1963. Living fossils Timeline of women in science Site with lots of photos Biography of Marjorie Courtenay-Latimer at the S2A3 Biographical Database of Southern African Science
The Indian Ocean is the third largest of the world's oceanic divisions, covering 70,560,000 km2. It is bounded by Asia on the north, on the west by Africa, on the east by Australia, on the south by the Southern Ocean or, depending on definition, by Antarctica; the Indian Ocean is named after India. Called the Sindhu Mahasagara or the great sea of the Sindhu by the Ancient Indians, this ocean has been variously called Hindu Ocean, Indic Ocean, etc. in various languages. The Indian Ocean was known earlier as the Eastern Ocean; the term was still in use during the mid-18th century. The borders of the Indian Ocean, as delineated by the International Hydrographic Organization in 1953 included the Southern Ocean but not the marginal seas along the northern rim, but in 2000 the IHO delimited the Southern Ocean separately, which removed waters south of 60°S from the Indian Ocean, but included the northern marginal seas. Meridionally, the Indian Ocean is delimited from the Atlantic Ocean by the 20° east meridian, running south from Cape Agulhas, from the Pacific Ocean by the meridian of 146°49'E, running south from the southernmost point of Tasmania.
The northernmost extent of the Indian Ocean is 30° north in the Persian Gulf. The Indian Ocean covers 70,560,000 km2, including the Red Sea and the Persian Gulf but excluding the Southern Ocean, or 19.5% of the world's oceans. The ocean's continental shelves are narrow. An exception is found off Australia's western coast; the average depth of the ocean is 3,890 m. Its deepest point is Sunda Trench at a depth of 7,450 m. North of 50° south latitude, 86% of the main basin is covered by pelagic sediments, of which more than half is globigerina ooze; the remaining 14% is layered with terrigenous sediments. Glacial outwash dominates the extreme southern latitudes; the major choke points include Bab el Mandeb, Strait of Hormuz, the Lombok Strait, the Strait of Malacca and the Palk Strait. Seas include the Gulf of Aden, Andaman Sea, Arabian Sea, Bay of Bengal, Great Australian Bight, Laccadive Sea, Gulf of Mannar, Mozambique Channel, Gulf of Oman, Persian Gulf, Red Sea and other tributary water bodies.
The Indian Ocean is artificially connected to the Mediterranean Sea through the Suez Canal, accessible via the Red Sea. All of the Indian Ocean is in the Eastern Hemisphere and the centre of the Eastern Hemisphere, the 90th meridian east, passes through the Ninety East Ridge. Marginal seas, gulfs and straits of the Indian Ocean include: Several features make the Indian Ocean unique, it constitutes the core of the large-scale Tropical Warm Pool which, when interacting with the atmosphere, affects the climate both regionally and globally. Asia prevents the ventilation of the Indian Ocean thermocline; that continent drives the Indian Ocean monsoon, the strongest on Earth, which causes large-scale seasonal variations in ocean currents, including the reversal of the Somali Current and Indian Monsoon Current. Because of the Indian Ocean Walker circulation there is no continuous equatorial easterlies. Upwelling occurs near the Horn of Africa and the Arabian Peninsula in the Northern Hemisphere and north of the trade winds in the Southern Hemisphere.
The Indonesian Throughflow is a unique Equatorial connection to the Pacific. The climate north of the equator is affected by a monsoon climate. Strong north-east winds blow from October until April. In the Arabian Sea the violent Monsoon brings rain to the Indian subcontinent. In the southern hemisphere, the winds are milder, but summer storms near Mauritius can be severe; when the monsoon winds change, cyclones sometimes strike the shores of the Arabian Sea and the Bay of Bengal. The Indian Ocean is the warmest ocean in the world. Long-term ocean temperature records show a rapid, continuous warming in the Indian Ocean, at about 0.7–1.2 °C during 1901–2012. Indian Ocean warming is the largest among the tropical oceans, about 3 times faster than the warming observed in the Pacific. Research indicates that human induced greenhouse warming, changes in the frequency and magnitude of El Niño events are a trigger to this strong warming in the Indian Ocean. South of the Equator the Indian Ocean is gaining heat from June to October, during the austral winter, while it is losing heat from November to March, during the austral summer.
Among the few large rivers flowing into the Indian Ocean are the Zambezi and Jubba in Africa. The ocean's currents are controlled by the monsoon. Two large gyres, one in the northern hemisphere flowing clockwise and one south of the equator moving anticlockwise, constitute the dominant flow pattern. During the winter monsoon, circulation is reversed north of 30°S and winds are weakened during winter and the transitional periods between the monsoons. Deep water circulation is controlled by inflows from the Atlantic Ocean, the Red Sea, Antarctic currents. North of 20 ° south latitude the minimum surface temperature is 22 °C. Southward of 40° south latitude, temperatures