Tropic of Capricorn
The Tropic of Capricorn is the circle of latitude that contains the subsolar point on the December solstice. It is thus the southernmost latitude, its northern equivalent is the Tropic of Cancer. The Tropic of Capricorn is one of the five major circles of latitude; as of 13 April 2019, its latitude is 23°26′12.4″ south of the Equator, but it is gradually moving northward at the rate of 0.47 arcseconds, or 15 metres, per year. When this line of latitude was named in the last centuries BC, the Sun was in the constellation Capricornus at the December solstice, the time each year that the Sun reaches its zenith at this latitude. Due to the precession of the equinoxes, this is no longer the case; the word "tropic" itself comes from the Greek "trope", meaning to turn or change direction, referring to the fact that the Sun appears to "turn back" at the solstices. The Tropic of Capricorn is the dividing line between the Southern Temperate Zone to the south and the tropics to the north; the Northern Hemisphere equivalent of the Tropic of Capricorn is the Tropic of Cancer.
The Tropic of Capricorn's position is not fixed, but changes because of a slight wobble in the Earth's longitudinal alignment relative to its orbit around the Sun. Earth's axial tilt varies over a 41,000 year period from 22.1 to 24.5 degrees and resides at about 23.4 degrees. This wobble means that the Tropic of Capricorn is drifting northward at a rate of half an arcsecond of latitude, or 15 metres, per year. See under circles of latitude for information. There are 13 hours, 35 minutes of daylight during the summer solstice. During the winter solstice, there are 41 minutes of daylight. In southern Africa, where rainfall is reliable, farming is possible, though yields are low with fertilisers. In Australia, areas on the Tropic have some of the most variable rainfall in the world and thus the wetter areas cannot be farmed, since irrigation sources invariably dry up in drought years. In South America, whilst in the continental cratons soils are as old as in Australia and Southern Africa, the presence of the geologically young and evolving Andes means that this region is on the western side of the subtropical anticyclones and thus receives warm and humid air from the Atlantic Ocean.
As a result, areas in Brazil adjacent to the Tropic are important agricultural regions, producing large quantities of crops such as sugarcane, the natural rainforest vegetation has been entirely cleared, except for a few remaining patches of Atlantic Forest. Further south in Argentina, the temperate grasslands of the Pampas region is one of the most productive agricultural regions in the world, producing of wheat, soybeans and beef, making the country one of the largest worldwide agricultural exporters, similar to the role played by the Prairies region in Canada. West of the Andes, the Humboldt Current makes conditions arid, creating the Atacama Desert, one of the driest in the world, so that no glaciers exist between Volcán Sajama at 18˚30'S and Cerro Tres Cruces at 27˚S. Vegetation here is non-existent, though on the eastern slopes of the Andes rainfall is adequate for rainfed agriculture. Starting at the Prime Meridian and heading eastwards, the Tropic of Capricorn passes through 10 countries: The following cities and landmarks are either located near the Tropic of Capricorn, or the tropic passes through them.
As the major portion of earth's land is located in the Northern Hemisphere there are only four countries south of the Tropic of Capricorn: Lesotho New Zealand Eswatini Uruguay Length of the Tropic on 11 June 2015, at 23°26′14″S is 36,788 kilometres. Temporal Epoch Calculations Useful constants" See: Obliquity of the ecliptic Montana State University: Milankovitch Cycles & Glaciation Circle of latitude Arctic Circle Tropic of Cancer Equator 23rd parallel south 24th parallel south Antarctic Circle Axial tilt Milankovitch cycles Capricornus
French Polynesia is an overseas collectivity of the French Republic and the only overseas country of France. It is composed of 118 geographically dispersed islands and atolls stretching over an expanse of more than 2,000 kilometres in the South Pacific Ocean, its total land area is 4,167 square kilometres. French Polynesia is divided into five groups of islands: the Society Islands archipelago, composed of the Windward Islands and the Leeward Islands. Among its 118 islands and atolls, 67 are inhabited. Tahiti, located within the Society Islands, is the most populous island, having close to 69% of the population of French Polynesia as of 2017. Papeete, located on Tahiti, is the capital. Although not an integral part of its territory, Clipperton Island was administered from French Polynesia until 2007. Following the Great Polynesian Migration, European explorers visited the islands of French Polynesia on several occasions. Traders and whaling ships visited. In 1842, the French took over the islands and established a French protectorate they called Etablissements des français en Océanie.
In 1946, the EFOs became an overseas territory under the constitution of the French Fourth Republic, Polynesians were granted the right to vote through citizenship. In 1957, the EFOs were renamed French Polynesia. In 1983 French Polynesia became a member of the Pacific Community, a regional development organization. Since 28 March 2003, French Polynesia has been an overseas collectivity of the French Republic under the constitutional revision of article 74, gained, with law 2004-192 of 27 February 2004, an administrative autonomy, two symbolic manifestations of which are the title of the President of French Polynesia and its additional designation as an overseas country. French Polynesia was one of the last places on Earth to be settled by humans. Scientists believe the Great Polynesian Migration happened around 1500 BC as Austronesian people went on a journey using celestial navigation to find islands in the South Pacific Ocean; the first islands of French Polynesia to be settled were the Marquesas Islands in about 200 BC.
The Polynesians ventured southwest and discovered the Society Islands around AD 300. European encounters began in 1521 when Portuguese explorer Ferdinand Magellan, sailing at the service of the Spanish Crown, sighted Puka-Puka in the Tuāmotu-Gambier Archipelago. In 1606 another Spanish expedition under Pedro Fernandes de Queirós sailed through Polynesia sighting an inhabited island on 10 February which they called Sagitaria the island of Rekareka to the southeast of Tahiti. Over a century British explorer Samuel Wallis visited Tahiti in 1767. French explorer Louis Antoine de Bougainville visited Tahiti in 1768, while British explorer James Cook arrived in 1769. In 1772, the Spanish Viceroy of Peru Don Manuel de Amat ordered a number of expeditions to Tahiti under the command of Domingo de Bonechea, the first European to explore all of the main islands beyond Tahiti. A short-lived Spanish settlement was created in 1774, for a time some maps bore the name Isla de Amat after Viceroy Amat. In 1772, Dutchman Jakob Roggeveen came across Bora Bora in the Society Islands.
Christian missions began with Spanish priests. Protestants from the London Missionary Society settled permanently in Polynesia in 1797. King Pōmare II of Tahiti was forced to flee to Mo'orea in 1803. French Catholic missionaries arrived on Tahiti in 1834. In 1842, Tahiti and Tahuata were declared a French protectorate, to allow Catholic missionaries to work undisturbed; the capital of Papeetē was founded in 1843. In 1880, France annexed Tahiti; the island groups were not united until the establishment of the French protectorate in 1889. After France declared a protectorate over Tahiti in 1840, the British and French signed the Jarnac Convention in 1847, declaring that the kingdoms of Raiatea and Bora Bora were to remain independent from either powers and that no single chief was to be allowed to reign over the entire archipelago. France broke the agreement, the islands were annexed and became a colony in 1888 after many native resistances and conflicts called the Leewards War, lasting until 1897.
In the 1880s, France claimed the Tuamotu Archipelago, which belonged to the Pōmare Dynasty, without formally annexing it. Having declared a protectorate over Tahuata in 1842, the French regarded the entire Marquesas Islands as French. In 1885, France appointed a governor and established a general council, thus giving it the proper administration for a colony; the islands of Rimatara and Rūrutu unsuccessfully lobbied for British protection in 1888, so in 1889 they were annexed by France. Postage stamps were first issued in the colony in 1892; the first official name for the colony was Établissements de l'Océanie. In 1940, the administration of French Polynesia recognised the Free French Forces and many Polynesians served in World War II. Unknown at the time to the French and Polynesians, the Konoe Cabinet in Imperial Japan on 16 September 1940 included French Polynesia among the many territories whic
Kota Kinabalu known as Jesselton, is the state capital of Sabah and the capital of the Kota Kinabalu District. It is the capital of the West Coast Division of Sabah; the city is located on the northwest coast of Borneo facing the South China Sea. The Tunku Abdul Rahman National Park lies to its west and Mount Kinabalu, which gave the city its name, is located to its east. Kota Kinabalu has a population of 452,058 according to the 2010 census. In the 15th century, the area of Kota Kinabalu was under the influence of Bruneian Empire. In the 19th century, the British North Borneo Company first set up a settlement near the Gaya Island. However, it was destroyed by fire in 1897 by a local leader named Mat Salleh. In July 1899, the place located opposite to the Gaya Island was identified as a suitable place for settlements. Development in the area was started soon after that. Jesselton became a major trading port in the area, was connected to the North Borneo Railway. Jesselton was destroyed during World War II.
The Japanese occupation of Jesselton provoked several local uprisings notably the Jesselton Revolt but they were defeated by the Japanese. After the war, BNBC was unable to finance the high cost of reconstructions and the place was ceded to the British Crown Colony; the British Crown declared Jesselton as the new capital of North Borneo in 1946 and started to rebuild the town. After the formation of Malaysia, North Borneo was renamed as Sabah. In 1967, Jesselton was renamed as Kota Kinabalu, Kota being the Malay word for Fort and Kinabalu after the nearby Mount Kinabalu. Kota Kinabalu was granted city status in 2000. Kota Kinabalu is known as KK both in Malaysia and internationally, it is a popular gateway for travellers visiting Sabah and Borneo. Kinabalu Park is located about 90 kilometres from the city and there are many other tourist attractions in and around the city. Kota Kinabalu is one of the major industrial and commercial centres of East Malaysia; these two factors combine to make Kota Kinabalu one of the fastest growing cities in Malaysia.
Kota Kinabalu is named after Mount Kinabalu, situated about 50 kilometres east-northeast of the city. Kinabalu is derived from the name Aki Nabalu meaning the "revered place of the dead." Aki means "ancestors" or "grandfather", Nabalu is a name for the mountain in the Dusun language. There is a source claiming that the term originated from Ki Nabalu, Ki meaning "have" or "exist", Nabalu meaning "spirit of the dead". Kota is a Malay word for a "fort", "town", or a "city", it is used formally in a few other Malaysian towns and cities, for example, Kota Bharu, Kota Tinggi, Kota Kemuning. It can be used informally to refer to any towns or cities. Hence, a direct translation of the name Kota Kinabalu into English would be "City of Kinabalu" or "Kinabalu City". Besides Jesselton, there are other older names for Kota Kinabalu; the most popular is Api-Api, or Api, a Malay word meaning'Fire'. Wendy Law Suart wrote in her book on North Borneo, The Lingering Eye, "there is in the Sabah State Museum a Dutch map of Borneo and the Celebes dated 1657 in which the settlement where Jesselton was to stand is labelled Api Api.
It may have some connection with the seaside tree with breathing roots that bears the same name". There are claims, that Kota Kinabalu was named after a nearby river called Sungai Api-Api. In Chinese, the city is still known as'Api', the Hakka pronunciation for 亚庇. Another suggested historical name is Deasoka, which means "below the coconut tree" in the Bajau language; the Bajau locals purportedly used this name to refer to a village in the southern part of the city, filled with coconut trees. Yet another name was Singgah Mata which means "transit eye", but can be loosely translated as "pleasing to the eye", it is a name said to have been given by fishermen from Gaya Island referring to the strip of land, today's downtown Kota Kinabalu. Today, all these names have been immortalised as names of buildings around the city; some examples are Api-Api Centre and Singgah Mata Street. Since the 15th century, the area of Jesselton was under the influence of the Bruneian Empire. In the late 1800s, the British North Borneo Company began to establish colonies throughout North Borneo.
In 1882, BNBC founded a small settlement in the area known as Gaya Bay, inhabited by Bajau people. The first settlement was on Gaya Island. In 1897, this first settlement was burned and destroyed by the indigenous Bajau-Suluk chief Mat Salleh. After the destruction, BNBC decided to relocate the settlement to the more defended mainland at Gantian Bay in 1898; however that location was found to be unsuitable and in July 1899, Mr. Henry Walker, a Land Commissioner, identified a 30 acres site opposite Gaya Island as a replacement for Gantian; this fishing village named Api-Api was chosen due to its proximity to the North Borneo Railway and its natural port that provided good anchorage, up to 24 feet deep. By the end of 1899, construction had started on a pier and government buildings; this new administrative centre was renamed Jesselton after Sir Charles Jessel, the Vice-Chairman of BNBC. Jesselton became a major trading post
Malaysia is a country in Southeast Asia. The federal constitutional monarchy consists of 13 states and three federal territories, separated by the South China Sea into two sized regions, Peninsular Malaysia and East Malaysia. Peninsular Malaysia shares a land and maritime border with Thailand and maritime borders with Singapore and Indonesia. East Malaysia shares land and maritime borders with Brunei and Indonesia and a maritime border with the Philippines and Vietnam. Kuala Lumpur is the national capital and largest city while Putrajaya is the seat of federal government. With a population of over 30 million, Malaysia is the world's 44th most populous country; the southernmost point of continental Eurasia, Tanjung Piai, is in Malaysia. In the tropics, Malaysia is one of 17 megadiverse countries, with large numbers of endemic species. Malaysia has its origins in the Malay kingdoms which, from the 18th century, became subject to the British Empire, along with the British Straits Settlements protectorate.
Peninsular Malaysia was unified as the Malayan Union in 1946. Malaya was restructured as the Federation of Malaya in 1948, achieved independence on 31 August 1957. Malaya united with North Borneo and Singapore on 16 September 1963 to become Malaysia. In 1965, Singapore was expelled from the federation; the country is multi-cultural, which plays a large role in its politics. About half the population is ethnically Malay, with large minorities of Malaysian Chinese, Malaysian Indians, indigenous peoples. While recognising Islam as the country's established religion, the constitution grants freedom of religion to non-Muslims; the government system is modelled on the Westminster parliamentary system and the legal system is based on common law. The head of state is the king, known as the Yang di-Pertuan Agong, he is an elected monarch chosen from the hereditary rulers of the nine Malay states every five years. The head of government is the Prime Minister; the country's official language is a standard form of the Malay language.
English remains an active second language. Since independence, Malaysian GDP has grown at an average of 6.5% per annum for 50 years. The economy has traditionally been fuelled by its natural resources, but is expanding in the sectors of science, tourism and medical tourism. Today, Malaysia has a newly industrialised market economy, ranked fourth largest in Southeast Asia and 38th largest in the world, it is a founding member of the Association of Southeast Asian Nations, the East Asia Summit and the Organisation of Islamic Cooperation, a member of Asia-Pacific Economic Cooperation, the Commonwealth of Nations, the Non-Aligned Movement. The name "Malaysia" is a combination of the word "Malay" and the Latin-Greek suffix "-sia"/-σία; the word "melayu" in Malay may derive from the Tamil words "malai" and "ur" meaning "mountain" and "city, land", respectively. "Malayadvipa" was the word used by ancient Indian traders. Whether or not it originated from these roots, the word "melayu" or "mlayu" may have been used in early Malay/Javanese to mean to accelerate or run.
This term was applied to describe the strong current of the river Melayu in Sumatra. The name was adopted by the Melayu Kingdom that existed in the seventh century on Sumatra. Before the onset of European colonisation, the Malay Peninsula was known natively as "Tanah Melayu". Under a racial classification created by a German scholar Johann Friedrich Blumenbach, the natives of maritime Southeast Asia were grouped into a single category, the Malay race. Following the expedition of French navigator Jules Dumont d'Urville to Oceania in 1826, he proposed the terms of "Malaysia", "Micronesia" and "Melanesia" to the Société de Géographie in 1831, distinguishing these Pacific cultures and island groups from the existing term "Polynesia". Dumont d'Urville described Malaysia as "an area known as the East Indies". In 1850, the English ethnologist George Samuel Windsor Earl, writing in the Journal of the Indian Archipelago and Eastern Asia, proposed naming the islands of Southeast Asia as "Melayunesia" or "Indunesia", favouring the former.
In modern terminology, "Malay" remains the name of an ethnoreligious group of Austronesian people predominantly inhabiting the Malay Peninsula and portions of the adjacent islands of Southeast Asia, including the east coast of Sumatra, the coast of Borneo, smaller islands that lie between these areas. The state that gained independence from the United Kingdom in 1957 took the name the "Federation of Malaya", chosen in preference to other potential names such as "Langkasuka", after the historic kingdom located at the upper section of the Malay Peninsula in the first millennium CE; the name "Malaysia" was adopted in 1963 when the existing states of the Federation of Malaya, plus Singapore, North Borneo and Sarawak formed a new federation. One theory posits the name was chosen so that "si" represented the inclusion of Singapore, North Borneo, Sarawak to Malaya in 1963. Politicians in the Philippines contemplated renaming their state "Malaysia" before the modern country took the name. Evidence of modern human habitation in Malaysia dates back 40,000 years.
In the Malay Peninsula, the first inhabitants are thought to be Negritos. Traders and settlers from India and China arrived as early as the first century AD, establishing trading ports and coastal towns in the second and third centuries, their presence resulted in strong Indian and Chinese influences on the local cultures, the people of the Malay Peninsula adopted the religions of Hinduism and Buddhism. Sanskrit inscriptions appear as early as the fifth century; the Kingdom of
Argentina the Argentine Republic, is a country located in the southern half of South America. Sharing the bulk of the Southern Cone with Chile to the west, the country is bordered by Bolivia and Paraguay to the north, Brazil to the northeast and the South Atlantic Ocean to the east, the Drake Passage to the south. With a mainland area of 2,780,400 km2, Argentina is the eighth-largest country in the world, the fourth largest in the Americas, the largest Spanish-speaking nation; the sovereign state is subdivided into twenty-three provinces and one autonomous city, Buenos Aires, the federal capital of the nation as decided by Congress. The provinces and the capital exist under a federal system. Argentina claims sovereignty over part of Antarctica, the Falkland Islands, South Georgia and the South Sandwich Islands; the earliest recorded human presence in modern-day Argentina dates back to the Paleolithic period. The Inca Empire expanded to the northwest of the country in Pre-Columbian times; the country has its roots in Spanish colonization of the region during the 16th century.
Argentina rose as the successor state of the Viceroyalty of the Río de la Plata, a Spanish overseas viceroyalty founded in 1776. The declaration and fight for independence was followed by an extended civil war that lasted until 1861, culminating in the country's reorganization as a federation of provinces with Buenos Aires as its capital city; the country thereafter enjoyed relative peace and stability, with several waves of European immigration radically reshaping its cultural and demographic outlook. The almost-unparalleled increase in prosperity led to Argentina becoming the seventh wealthiest nation in the world by the early 20th century. Following the Great Depression in the 1930s, Argentina descended into political instability and economic decline that pushed it back into underdevelopment, though it remained among the fifteen richest countries for several decades. Following the death of President Juan Perón in 1974, his widow, Isabel Martínez de Perón, ascended to the presidency, she was overthrown in 1976 by a U.
S.-backed coup which installed a right-wing military dictatorship. The military government persecuted and murdered numerous political critics and leftists in the Dirty War, a period of state terrorism that lasted until the election of Raúl Alfonsín as President in 1983. Several of the junta's leaders were convicted of their crimes and sentenced to imprisonment. Argentina is a prominent regional power in the Southern Cone and Latin America, retains its historic status as a middle power in international affairs. Argentina has the second largest economy in South America, the third-largest in Latin America, membership in the G-15 and G-20 major economies, it is a founding member of the United Nations, World Bank, World Trade Organization, Union of South American Nations, Community of Latin American and Caribbean States and the Organization of Ibero-American States. Despite its history of economic instability, it ranks second highest in the Human Development Index in Latin America; the description of the country by the word Argentina has been found on a Venetian map in 1536.
In English the name "Argentina" comes from the Spanish language, however the naming itself is not Spanish, but Italian. Argentina means in Italian " of silver, silver coloured" borrowed from the Old French adjective argentine " of silver" > "silver coloured" mentioned in the 12th century. The French word argentine is the feminine form of argentin and derives from argent "silver" with the suffix -in; the Italian naming "Argentina" for the country implies Terra Argentina "land of silver" or Costa Argentina "coast of silver". In Italian, the adjective or the proper noun is used in an autonomous way as a substantive and replaces it and it is said l'Argentina; the name Argentina was first given by the Venetian and Genoese navigators, such as Giovanni Caboto. In Spanish and Portuguese, the words for "silver" are plata and prata and " of silver" is said plateado and prateado. Argentina was first associated with the silver mountains legend, widespread among the first European explorers of the La Plata Basin.
The first written use of the name in Spanish can be traced to La Argentina, a 1602 poem by Martín del Barco Centenera describing the region. Although "Argentina" was in common usage by the 18th century, the country was formally named "Viceroyalty of the Río de la Plata" by the Spanish Empire, "United Provinces of the Río de la Plata" after independence; the 1826 constitution included the first use of the name "Argentine Republic" in legal documents. The name "Argentine Confederation" was commonly used and was formalized in the Argentine Constitution of 1853. In 1860 a presidential decree settled the country's name as "Argentine Republic", that year's constitutional amendment ruled all the names since 1810 as valid. In the English language the country was traditionally called "the Argentine", mimicking the typical Spanish usage la Argentina and resulting from a mistaken shortening of the fuller name'Argentine Republic'.'The Argentine' fell out of fashion during the mid-to-late 20th century, now the country is referred to as "Argentina".
In the Spanish language "Argentina" is feminine, taking the feminine article "La" as the i
Tropical rainforests are rainforests that occur in areas of tropical rainforest climate in which there is no dry season – all months have an average precipitation of at least 60 mm – and may be referred to as lowland equatorial evergreen rainforest. True rainforests are found between 10 degrees north and south of the equator. Within the World Wildlife Fund's biome classification, tropical rainforests are a type of tropical moist broadleaf forest that includes the more extensive seasonal tropical forests. Tropical rainforests can be characterized in two words: wet. Mean monthly temperatures exceed 18 °C during all months of the year. Average annual rainfall is no less than 1,680 mm and can exceed 10 m although it lies between 1,750 mm and 3,000 mm; this high level of precipitation results in poor soils due to leaching of soluble nutrients in the ground. Tropical rainforests exhibit high levels of biodiversity. Around 40% to 75% of all biotic species are indigenous to the rainforests. Rainforests are home to half of all the living plant species on the planet.
Two-thirds of all flowering plants can be found in rainforests. A single hectare of rainforest may contain 42,000 different species of insect, up to 807 trees of 313 species and 1,500 species of higher plants. Tropical rainforests have been called the "world's largest pharmacy", because over one quarter of natural medicines have been discovered within them, it is that there may be many millions of species of plants and microorganisms still undiscovered in tropical rainforests. Tropical rainforests are among the most threatened ecosystems globally due to large-scale fragmentation as a result of human activity. Habitat fragmentation caused by geological processes such as volcanism and climate change occurred in the past, have been identified as important drivers of speciation. However, fast human driven habitat destruction is suspected to be one of the major causes of species extinction. Tropical rain forests have been subjected to heavy logging and agricultural clearance throughout the 20th century, the area covered by rainforests around the world is shrinking.
Tropical rainforests have existed on earth for hundreds of millions of years. Most tropical rainforests today are on fragments of the Mesozoic era supercontinent of Gondwana; the separation of the landmass resulted in a great loss of amphibian diversity while at the same time the drier climate spurred the diversification of reptiles. The division left tropical rainforests located in five major regions of the world: tropical America, Southeast Asia and New Guinea, with smaller outliers in Australia. However, the specifics of the origin of rainforests remain uncertain due to an incomplete fossil record. Several biomes may appear similar-to, or merge via ecotones with, tropical rainforest: Moist seasonal tropical forest Moist seasonal tropical forests receive high overall rainfall with a warm summer wet season and a cooler winter dry season; some trees in these forests drop some or all of their leaves during the winter dry season, thus they are sometimes called "tropical mixed forest". They are found in parts of South America, in Central America and around the Caribbean, in coastal West Africa, parts of the Indian subcontinent, across much of Indochina.
Montane rainforests These are found in cooler-climate mountainous areas, becoming known as cloud forests at higher elevations. Depending on latitude, the lower limit of montane rainforests on large mountains is between 1500 and 2500 m while the upper limit is from 2400 to 3300 m. Flooded rainforests Tropical freshwater swamp forests, or "flooded forests", are found in Amazon basin and elsewhere. Rainforests are divided into different strata, or layers, with vegetation organized into a vertical pattern from the top of the soil to the canopy; each layer is a unique biotic community containing different plants and animals adapted for life in that particular strata. Only the emergent layer is unique to tropical rainforests, while the others are found in temperate rainforests; the forest floor, the bottom-most layer, receives only 2% of the sunlight. Only plants adapted to low light can grow in this region. Away from riverbanks and clearings, where dense undergrowth is found, the forest floor is clear of vegetation because of the low sunlight penetration.
This more open quality permits the easy movement of larger animals such as: ungulates like the okapi, Sumatran rhinoceros, apes like the western lowland gorilla, as well as many species of reptiles and insects. The forest floor contains decaying plant and animal matter, which disappears because the warm, humid conditions promote rapid decay. Many forms of fungi growing here help decay the plant waste; the understory layer lies between the forest floor. The understory is home to a number of birds, small mammals, insects and predators. Examples include leopard, poison dart frogs, ring-tailed coati, boa constrictor, many species of Coleoptera; the vegetation at this layer consists of shade-tolerant shrubs, small trees, large woody vines which climb into the trees to capture sunlight. Only about 5% of sunlight breaches the canopy to arrive at the understory causing true understory plants to grow to 3 m; as an
Earth is the third planet from the Sun and the only astronomical object known to harbor life. According to radiometric dating and other sources of evidence, Earth formed over 4.5 billion years ago. Earth's gravity interacts with other objects in space the Sun and the Moon, Earth's only natural satellite. Earth revolves around the Sun in a period known as an Earth year. During this time, Earth rotates about its axis about 366.26 times. Earth's axis of rotation is tilted with respect to its orbital plane; the gravitational interaction between Earth and the Moon causes ocean tides, stabilizes Earth's orientation on its axis, slows its rotation. Earth is the largest of the four terrestrial planets. Earth's lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earth's surface is covered with water by oceans; the remaining 29% is land consisting of continents and islands that together have many lakes and other sources of water that contribute to the hydrosphere.
The majority of Earth's polar regions are covered in ice, including the Antarctic ice sheet and the sea ice of the Arctic ice pack. Earth's interior remains active with a solid iron inner core, a liquid outer core that generates the Earth's magnetic field, a convecting mantle that drives plate tectonics. Within the first billion years of Earth's history, life appeared in the oceans and began to affect the Earth's atmosphere and surface, leading to the proliferation of aerobic and anaerobic organisms; some geological evidence indicates. Since the combination of Earth's distance from the Sun, physical properties, geological history have allowed life to evolve and thrive. In the history of the Earth, biodiversity has gone through long periods of expansion punctuated by mass extinction events. Over 99% of all species that lived on Earth are extinct. Estimates of the number of species on Earth today vary widely. Over 7.6 billion humans live on Earth and depend on its biosphere and natural resources for their survival.
Humans have developed diverse cultures. The modern English word Earth developed from a wide variety of Middle English forms, which derived from an Old English noun most spelled eorðe, it has cognates in every Germanic language, their proto-Germanic root has been reconstructed as *erþō. In its earliest appearances, eorðe was being used to translate the many senses of Latin terra and Greek γῆ: the ground, its soil, dry land, the human world, the surface of the world, the globe itself; as with Terra and Gaia, Earth was a personified goddess in Germanic paganism: the Angles were listed by Tacitus as among the devotees of Nerthus, Norse mythology included Jörð, a giantess given as the mother of Thor. Earth was written in lowercase, from early Middle English, its definite sense as "the globe" was expressed as the earth. By Early Modern English, many nouns were capitalized, the earth became the Earth when referenced along with other heavenly bodies. More the name is sometimes given as Earth, by analogy with the names of the other planets.
House styles now vary: Oxford spelling recognizes the lowercase form as the most common, with the capitalized form an acceptable variant. Another convention capitalizes "Earth" when appearing as a name but writes it in lowercase when preceded by the, it always appears in lowercase in colloquial expressions such as "what on earth are you doing?" The oldest material found in the Solar System is dated to 4.5672±0.0006 billion years ago. By 4.54±0.04 Bya the primordial Earth had formed. The bodies in the Solar System evolved with the Sun. In theory, a solar nebula partitions a volume out of a molecular cloud by gravitational collapse, which begins to spin and flatten into a circumstellar disk, the planets grow out of that disk with the Sun. A nebula contains gas, ice grains, dust. According to nebular theory, planetesimals formed by accretion, with the primordial Earth taking 10–20 million years to form. A subject of research is the formation of some 4.53 Bya. A leading hypothesis is that it was formed by accretion from material loosed from Earth after a Mars-sized object, named Theia, hit Earth.
In this view, the mass of Theia was 10 percent of Earth, it hit Earth with a glancing blow and some of its mass merged with Earth. Between 4.1 and 3.8 Bya, numerous asteroid impacts during the Late Heavy Bombardment caused significant changes to the greater surface environment of the Moon and, by inference, to that of Earth. Earth's atmosphere and oceans were formed by volcanic outgassing. Water vapor from these sources condensed into the oceans, augmented by water and ice from asteroids and comets. In this model, atmospheric "greenhouse gases" kept the oceans from freezing when the newly forming Sun had only 70% of its current luminosity. By 3.5 Bya, Earth's magnetic field was established, which helped prevent the atmosphere from being stripped away by the solar wind. A crust formed; the two models that explain land mass propose either a steady growth to the present-day forms or, more a rapid growth early in Earth history followed by a long-term steady continental area. Continents formed by plate tectonics