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Tassili N'Ajjer
Tassili n'Ajjer (Berber: ''Tassili n Ajjer'', ; "Plateau of rivers") is a mountain range in the Sahara desert, located in south-eastern Algeria. It holds one of the most important groupings of prehistoric cave art in the world, and covers an area of more than , The site has been designated a national park and a Biosphere Reserve, and was inducted into the UNESCO World Heritage Site list in 1982. The literal English translation of ''Tassili n'Ajjer'' is 'plateau of rivers'. Geography Tassili n'Ajjer is a plateau in south-eastern Algeria at the borders of Libya and Nigeri, covering an area of 72,000 km2. It ranges from east-south-east to . Its highest point is the Adrar Afao that peaks at , located at . The nearest town is Djanet, about to the south-west. The plateau is of great geological and aesthetic interest. Its panorama of geological formations of rock forests, composed of eroded sandstone, resembles a lunar landscape and hosts a range of rock art styles. Geolog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algeria
Algeria, officially the People's Democratic Republic of Algeria, is a country in the Maghreb region of North Africa. It is bordered to Algeria–Tunisia border, the northeast by Tunisia; to Algeria–Libya border, the east by Libya; to Algeria–Niger border, the southeast by Niger; to Algeria–Western Sahara border, the southwest by Mali, Mauritania, and Western Sahara; to Algeria–Morocco border, the west by Morocco; and to the north by the Mediterranean Sea. The capital and List of cities in Algeria, largest city is Algiers, located in the far north on the Mediterranean coast. Inhabited since prehistory, Algeria has been at the crossroads of numerous cultures and civilisations, including the Phoenicians, Numidians, Ancient Rome, Romans, Vandals, and Byzantine Greeks. Its modern identity is rooted in centuries of Arab migrations to the Maghreb, Arab Muslim migration waves since Muslim conquest of the Maghreb, the seventh century and the subsequent Arabization, Arabisation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
West Saharan Montane Xeric Woodlands
The West Saharan montane xeric woodlands is an ecoregion that extends across several highland regions in the Sahara. Surrounded at lower elevations by the largely barren Sahara, the West Saharan montane xeric woodlands are isolated refuges of plants and animals that can survive in the higher humidity and lower temperatures of the highlands. Setting The Sahara is a vast desert, stretching across northern Africa from the Atlantic Ocean to the Red Sea. Some mountains ranges (such as the Ahaggar, Tassili n'Ajjer, Tibesti and Aïr) rise up from the desert and receive more rainfall and mostly present slightly cooler summer temperatures. These highlands support dry woodlands and shrublands distinct from the hot dry desert lowlands. This ecoregion has an area of . The boundaries for the largest part of this ecoregion, which includes the Tassili n'Ajjer Ahaggar and Aïr (or Azbine) massifs, follow the ' regs,' ' hamadas' and ' wadis' above the 1,000 m contour. This covers a good p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
West Africa
West Africa, also known as Western Africa, is the westernmost region of Africa. The United Nations geoscheme for Africa#Western Africa, United Nations defines Western Africa as the 16 countries of Benin, Burkina Faso, Cape Verde, The Gambia, Ghana, Guinea, Guinea-Bissau, Ivory Coast, Liberia, Mali, Mauritania, Niger, Nigeria, Senegal, Sierra Leone, and Togo, as well as Saint Helena, Ascension and Tristan da Cunha (United Kingdom Overseas Territories, United Kingdom Overseas Territory).Paul R. Masson, Catherine Anne Pattillo, "Monetary union in West Africa (ECOWAS): is it desirable and how could it be achieved?" (Introduction). International Monetary Fund, 2001. The population of West Africa is estimated at around million people as of , and at 381,981,000 as of 2017, of which 189,672,000 were female and 192,309,000 male.United Nations Department of Economic and Social Affairs, Population Division (2017). World Population Prospects: The 2017 Revision, custom data acquired via webs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
West African Crocodile
The West African crocodile, desert crocodile, or sacred crocodile (''Crocodylus suchus'') is a species of crocodile related to, and often confused with, the larger and more aggressive Nile crocodile (''C. niloticus''). Taxonomy The species was named by Étienne Geoffroy Saint-Hilaire in 1807, who discovered differences between the skulls of a Animal mummy, mummified crocodile and those of Nile crocodile (''C. niloticus''). However, this new species was long afterwards regarded as a Synonym (taxonomy), synonym of the Nile crocodile. In 2003, a study resurrected ''C. suchus'' as a valid species, and this was confirmed by several other studies conducted between 2011 and 2015. Despite the long history of confusion, Genetics, genetic testing has revealed that the two are not particularly close. The closest relatives of the Nile crocodile are the ''Crocodylus'' species from the Americas, while the West African crocodile is Basal (phylogenetics), basal to the clade of Nile and Americ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Western United States
The Western United States (also called the American West, the Western States, the Far West, the Western territories, and the West) is List of regions of the United States, census regions United States Census Bureau. As American settlement in the U.S. Manifest destiny, expanded westward, the meaning of the term ''the West'' changed. Before around 1800, the crest of the Appalachian Mountains was seen as the American frontier, western frontier. The frontier moved westward and eventually the lands west of the Mississippi River were considered ''the West''. The U.S. Census Bureau's definition of the 13 westernmost states includes the Rocky Mountains and the Great Basin to the West Coast of the United States, Pacific Coast, and the mid-Pacific islands state, Hawaii. To the east of the Western United States is the Midwestern United States and the Southern United States, with Canada to the north and Mexico to the south. The West contains several major biomes, including arid and Sem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bristlecone Pine
The term bristlecone pine covers three species of pine tree (family Pinaceae, genus ''Pinus'', subsection ''Balfourianae''). All three species are long-lived and highly resilient to harsh weather and bad soils. One of the three species, ''Pinus longaeva'', is among the longest-lived life forms on Earth. The oldest of this species is more than 4,800 years old, making it the oldest known individual of any species. Many scientists are curious as to why this tree is able to live so long. In one study, they discovered that ''Pinus longaeva'' has higher levels of telomerase activity, which further slows or prevents the attrition rate of telomeres. This potentially contributes to the extended life of the bristlecone pine. Despite their potential age and low reproductive rate, bristlecone pines, particularly ''Pinus longaeva'', are usually a first-succession species, tending to occupy new open ground. They generally compete poorly in less-than-harsh environments, making them hard to c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myrtus Nivellei
''Myrtus'' (commonly called myrtle) is a genus of flowering plants in the family Myrtaceae. It was first described by Swedish botanist Linnaeus in 1753. Over 600 names have been proposed in the genus, but nearly all have either been moved to other genera or been regarded as synonyms. The genus ''Myrtus'' has three species recognised today: *''Myrtus communis'' – Common myrtle; native to the Mediterranean region in southern Europe *''Myrtus nivellei'' – Saharan myrtle; native to North Africa *'' Myrtus phyllireaefolia'' Description Common myrtle ''Myrtus communis'', the "common myrtle", is native across the Mediterranean region, Macaronesia, western Asia, and the Indian subcontinent. It is also cultivated. The plant is an evergreen shrub or small tree, growing to tall. The leaf is entire, 3–5 cm long, with a fragrant essential oil. The star-like flower has five petals and sepals, and numerous stamens. Petals usually are white. The flower is pollinated by ins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cupressus Dupreziana
''Cupressus dupreziana'', the Saharan cypress, or tarout, is a very rare coniferous tree native to the Tassili n'Ajjer mountains in the central Sahara desert, southeast Algeria, where it forms a unique population of trees hundreds of kilometres from any other trees. There are only 233 specimens of this endangered species, the largest about 22 m tall. The majority are estimated to be over 2000 years old, with very little regeneration due to the increasing desertification of the Sahara. Rainfall totals in the area are estimated to be about 30 mm annually. The largest one is named Tin-Balalan is believed to be the oldest tarout tree with a circumference of 12 meters or 36 feet. This species is distinct from the allied ''Cupressus sempervirens'' (Mediterranean cypress) in its much bluer foliage with a white resin spot on each leaf, the smaller shoots often being flattened in a single plane. It also has smaller cones, only 1.5–2.5 cm long. '' Cupressus atlantica'' (Moroc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemic (ecology)
Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be ''endemic'' to that particular part of the world. An endemic species can also be referred to as an ''endemism'' or, in scientific literature, as an ''endemite''. Similarly, many species found in the Western ghats of India are examples of endemism. Endemism is an important concept in conservation biology for measuring biodiversity in a particular place and evaluating the risk of extinction for species. Endemism is also of interest in evolutionary biology, because it provides clues about how changes in the environment cause species to undergo range shifts (potentially expanding their range into a larger area or bec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endangered Species
An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching, invasive species, and climate change. The International Union for Conservation of Nature (IUCN) Red List lists the global conservation status of many species, and various other agencies assess the status of species within particular areas. Many nations have laws that protect conservation-reliant species which, for example, forbid hunting, restrict land development, or create protected areas. Some endangered species are the target of extensive conservation efforts such as captive breeding and habitat restoration. Human activity is a significant cause in causing some species to become endangered. Conservation status The conservation status of a species indicates the likelihood that it will become extinct. Multiple factors are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammal
A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three Evolution of mammalian auditory ossicles, middle ear bones. These characteristics distinguish them from reptiles and birds, from which their ancestors Genetic divergence, diverged in the Carboniferous Period over 300 million years ago. Around 6,640 Neontology#Extant taxon, extant species of mammals have been described and divided into 27 Order (biology), orders. The study of mammals is called mammalogy. The largest orders of mammals, by number of species, are the rodents, bats, and eulipotyphlans (including hedgehogs, Mole (animal), moles and shrews). The next three are the primates (including humans, monkeys and lemurs), the Artiodactyl, even-toed ungulates (including pigs, camels, and whales), and the Carnivora (including Felidae, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Food Chain
A food chain is a linear network of links in a food web, often starting with an autotroph (such as grass or algae), also called a producer, and typically ending at an apex predator (such as grizzly bears or killer whales), detritivore (such as earthworms and woodlice), or decomposer (such as fungi or bacteria). It is not the same as a food web. A food chain depicts relations between species based on what they consume for energy in trophic levels, and they are most commonly quantified in length: the number of links between a trophic consumer and the base of the chain. Food chain studies play an important role in many biological studies. Food chain stability is very important for the survival of most species. When only one element is removed from the food chain it can result in extinction or immense decreases of survival of a species. Many food chains and food webs contain a keystone species, a species that has a large impact on the surrounding environment and that can directly a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
