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Microdictyon Marinum
''Microdictyon'' is an extinct armoured worm-like animal coated with net-like scleritic plates, known from the Early Cambrian Maotianshan shale of Yunnan China and other parts of the world. ''Microdictyon'' is part of the ill-defined taxon – Lobopodia – that includes several other odd worm-like animals that resembling worm with legs, such as '' Hallucigenia'', ''Onychodictyon'', '' Cardiodictyon'', '' Luolishania'', and '' Paucipodia''. The isolated sclerites of ''Microdictyon'' are known from other Lower Cambrian deposits. ''Microdictyon'' sclerites appear to have moulted; one sclerite seems to have been preserved during ecdysis.Figured in ''Microdictyon sinicum'' (Chen, Hou and Lu, 1989) is typical. The wormlike animal has ten pairs of sclerites (suggestions that these may be eyes or eye-like structures have no weight) on the sides, matched to a pair of tentacle-like feet below. The head and posterior are tubular and featureless. Species composition *Type ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Worm
Worms are many different distantly related bilateral animals that typically have a long cylindrical tube-like body, no limbs, and no eyes (though not always). Worms vary in size from microscopic to over in length for marine polychaete worms (bristle worms); for the African giant earthworm, '' Microchaetus rappi''; and for the marine nemertean worm (bootlace worm), '' Lineus longissimus''. Various types of worm occupy a small variety of parasitic niches, living inside the bodies of other animals. Free-living worm species do not live on land but instead live in marine or freshwater environments or underground by burrowing. In biology, "worm" refers to an obsolete taxon, '' vermes'', used by Carolus Linnaeus and Jean-Baptiste Lamarck for all non-arthropod invertebrate animals, now seen to be paraphyletic. The name stems from the Old English word '' wyrm''. Most animals called "worms" are invertebrates, but the term is also used for the amphibian caecilians and the slow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kazakhstan
Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eigh ... to Kazakhstan–Russia border, the north and west, China to China–Kazakhstan border, the east, Kyrgyzstan to Kazakhstan–Kyrgyzstan border, the southeast, Uzbekistan to Kazakhstan–Uzbekistan border, the south, and Turkmenistan to Kazakhstan–Turkmenistan border, the southwest, with a coastline along the Caspian Sea. Its capital is Astana, known as Nur-Sultan from 2019 to 2022. Almaty, Kazakhstan's largest city, was the country's capital until 1997. Kazakhstan is the world's largest landlocked country, the largest and northernmost Muslim world, Muslim-majority cou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yunnan
Yunnan , () is a landlocked province in the southwest of the People's Republic of China. The province spans approximately and has a population of 48.3 million (as of 2018). The capital of the province is Kunming. The province borders the Chinese provinces of Guizhou, Sichuan, autonomous regions of Guangxi, and Tibet as well as Southeast Asian countries: Vietnam, Laos, and Myanmar. Yunnan is China's fourth least developed province based on disposable income per capita in 2014. Yunnan is situated in a mountainous area, with high elevations in the northwest and low elevations in the southeast. Most of the population lives in the eastern part of the province. In the west, the altitude can vary from the mountain peaks to river valleys by as much as . Yunnan is rich in natural resources and has the largest diversity of plant life in China. Of the approximately 30,000 species of higher plants in China, Yunnan has perhaps 17,000 or more. Yunnan's reserves of aluminium, lead, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toyonian
Cambrian Stage 4 is the still unnamed fourth stage of the Cambrian and the upper stage of Cambrian Series 2. It follows Cambrian Stage 3 and lies below the Wuliuan. The lower boundary has not been formally defined by the International Commission on Stratigraphy. One proposal is the first appearance of two trilobite genera, '' Olenellus'' or ''Redlichia''. Another proposal is the first appearance of the trilobite species ''Arthricocephalus chauveaui ''Arthricocephalus'' is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the later part of the Botomian stage, which lasted from approximately 524 to 518.5 million years ago. This faunal stage ...''. Both proposals will set the lower boundary close to million years ago. The upper boundary corresponds to the beginning of the Wuliuan. Naming The International Commission on Stratigraphy has not named the fourth stage of the Cambrian yet. In the widely used Siberian nomenclatu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amgan
The Cambrian Period ( ; sometimes symbolized Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ago (mya) to the beginning of the Ordovician Period mya. Its subdivisions, and its base, are somewhat in flux. The period was established as "Cambrian series" by Adam Sedgwick, who named it after Cambria, the Latin name for 'Cymru' (Wales), where Britain's Cambrian rocks are best exposed. Sedgwick identified the layer as part of his task, along with Roderick Murchison, to subdivide the large "Transition Series", although the two geologists disagreed for a while on the appropriate categorization. The Cambrian is unique in its unusually high proportion of sedimentary deposits, sites of exceptional preservation where "soft" parts of organisms are preserved as well as their more resistant shells. As a result, our understanding of the Cambrian biolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by total area. Its southern and western border with the United States, stretching , is the world's longest binational land border. Canada's capital is Ottawa, and its three largest metropolitan areas are Toronto, Montreal, and Vancouver. Indigenous peoples have continuously inhabited what is now Canada for thousands of years. Beginning in the 16th century, British and French expeditions explored and later settled along the Atlantic coast. As a consequence of various armed conflicts, France ceded nearly all of its colonies in North America in 1763. In 1867, with the union of three British North American colonies through Confederation, Canada was formed as a federal dominion of four provinces. This began an accretion of provinces and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australia
Australia, officially the Commonwealth of Australia, is a sovereign ''Sovereign'' is a title which can be applied to the highest leader in various categories. The word is borrowed from Old French , which is ultimately derived from the Latin , meaning 'above'. The roles of a sovereign vary from monarch, ruler or ... country comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands. With an area of , Australia is the largest country by area in Oceania and the world's sixth-largest country. Australia is the oldest, flattest, and driest inhabited continent, with the least fertile soils. It is a megadiverse country, and its size gives it a wide variety of landscapes and climates, with deserts in the centre, tropical Forests of Australia, rainforests in the north-east, and List of mountains in Australia, mountain ranges in the south-east. The ancestors of Aboriginal Australians began arriving from south east Asia approx ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five major unincorporated territories, nine United States Minor Outlying Islands, Minor Outlying Islands, and 326 Indian reservations. The United States is also in Compact of Free Association, free association with three Oceania, Pacific Island Sovereign state, sovereign states: the Federated States of Micronesia, the Marshall Islands, and the Palau, Republic of Palau. It is the world's List of countries and dependencies by area, third-largest country by both land and total area. It shares land borders Canada–United States border, with Canada to its north and Mexico–United States border, with Mexico to its south and has maritime borders with the Bahamas, Cuba, Russia, and other nations. With a population of over 333 million, it is the List of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shaanxi
Shaanxi (alternatively Shensi, see § Name) is a landlocked province of China. Officially part of Northwest China, it borders the province-level divisions of Shanxi (NE, E), Henan (E), Hubei (SE), Chongqing (S), Sichuan (SW), Gansu (W), Ningxia (NW) and Inner Mongolia (N). Shaanxi covers an area of over with about 37 million people, the 16th highest in China. Xi'an – which includes the sites of the former Chinese capitals Fenghao and Chang'an – is the provincial capital as well as the largest city in Northwest China and also one of the oldest cities in China and the oldest of the Four Great Ancient Capitals, being the capital for the Western Zhou, Western Han, Jin, Sui and Tang dynasties. Xianyang, which served as the Qin dynasty capital, is just north across Wei River. The other prefecture-level cities into which the province is divided are Ankang, Baoji, Hanzhong, Shangluo, Tongchuan, Weinan, Yan'an and Yulin. The province is geographically div ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's List of countries and dependencies by population, most populous country, with a Population of China, population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and Borders of China, borders fourteen countries by land, the List of countries and territories by land borders, most of any country in the world, tied with Russia. Covering an area of approximately , it is the world's third List of countries and dependencies by area, largest country by total land area. The country consists of 22 provinces of China, provinces, five autonomous regions of China, autonomous regions, four direct-administered municipalities of China, municipalities, and two special administrative regions of China, Special Administrative Regions (Hong Kong and Macau). The national capital is Beijing, and the List of cities in China by population, most populous cit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sweden
Sweden, ; fi, Ruotsi; fit, Ruotti; se, Ruoŧŧa; smj, Svierik; sje, Sverji; sju, Sverje; sma, Sveerje or ; yi, שוועדן, Shvedn; rmu, Svedikko; rmf, Sveittiko. formally the Kingdom of Sweden, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, and Finland to the east. At , Sweden is the largest Nordic country and the List of European countries by area, fifth-largest country in Europe. The Capital city, capital and largest city is Stockholm. Sweden has a population of 10.5 million, and a low population density of ; around 87% of Swedes reside in urban areas in the central and southern half of the country. Sweden’s urban areas together cover 1.5% of its land area. Because the country is so long, ranging from 55th parallel north, 55°N to 69th parallel north, 69°N, the climate of Sweden is diverse. Sweden has been inhabited since Prehistoric Sweden, prehistoric times, . T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siberian Platform
Siberia, also known as Angaraland (or simply Angara) and Angarida, is an ancient craton in the heart of Siberia. Today forming the Central Siberian Plateau, it was an independent continent before the Permian period. The Verkhoyansk Sea, a passive continental margin, was fringing the Siberian Craton to the east in what is now the East Siberian Lowland. Angaraland was named in the 1880s by Austrian geologist Eduard Suess who erroneously believed that in the Paleozoic there were two large continents in the Northern Hemisphere: "Atlantis", North America connected to Europe by a peninsula (=Greenland and Iceland); and "Angara-land", eastern Asia, named after the Angara River in Siberia. Precambrian history About 2.5 billion years ago ( Siderian), Siberia was part of a continent called Arctica, along with the Canadian Shield. Around 1.1 billion years ago ( Stenian), Siberia became part of the supercontinent of Rodinia, a state of affairs which lasted until the Cryogenian about 750 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
