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Dark Skin
Dark skin is a type of human skin color that is rich in melanin pigments. People with dark skin are often referred to as black people, although this usage can be ambiguous in some countries where it is also used to specifically refer to different ethnic groups or populations. The evolution of dark skin is believed to have begun around 1.2 million years ago, in light-skinned early hominid species after they moved from the equatorial rainforest to the sunny savannas. In the heat of the savannas, better cooling mechanisms were required, which were achieved through the loss of body hair and development of more efficient perspiration. The loss of body hair led to the development of dark skin pigmentation, which acted as a mechanism of natural selection against folate (vitamin B9) depletion, and to a lesser extent, Direct DNA damage, DNA damage. The primary factor contributing to the evolution of dark skin pigmentation was the breakdown of folate in reaction to ultraviolet radiat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dress (Klashorst)-cropped
A dress (also known as a frock or a gown) is a one-piece outer garment that is worn on the torso, hangs down over the legs, and is primarily worn by women or girls. Dresses often consist of a bodice attached to a skirt. Dress shapes, silhouettes, Textile, textiles, and colors vary. In particular, dresses can vary by sleeve length, neckline, skirt length, or hemline. These variances may be based on considerations such as fashion trends, modesty, weather, and personal taste. Dresses are generally suitable for both formal wear and casual wear in the West. Historically, Foundation garment, foundation garments and other structural garments—including items such as Corset, corsets, partlets, petticoats, Pannier (clothing), panniers, and Bustle, bustles—were used to achieve the desired silhouette. History Middle Ages In the 11th century, women in Europe wore loose garments that were similar in shape to the tunics worn by men. Sleeves varied in fit and length, and hemlines fell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homo Sapiens
Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing#Evolution of hairlessness, hairlessness, bipedality, bipedalism, and high Human intelligence, intelligence. Humans have large Human brain, brains, enabling more advanced cognitive skills that facilitate successful adaptation to varied environments, development of sophisticated tools, and formation of complex social structures and civilizations. Humans are Sociality, highly social, with individual humans tending to belong to a Level of analysis, multi-layered network of distinct social groups — from families and peer groups to corporations and State (polity), political states. As such, social interactions between humans have established a wide variety of Value theory, values, norm (sociology), social norms, languages, and traditions (co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
West Asia
West Asia (also called Western Asia or Southwest Asia) is the westernmost region of Asia. As defined by most academics, UN bodies and other institutions, the subregion consists of Anatolia, the Arabian Peninsula, Iran, Mesopotamia, the Armenian highlands, the Levant, the island of Cyprus, the Sinai Peninsula and the South Caucasus. The region is separated from Africa by the Isthmus of Suez in Egypt, and separated from Europe by the waterways of the Turkish Straits and the watershed of the Greater Caucasus. Central Asia lies to its northeast, while South Asia lies to its east. Twelve seas surround the region (clockwise): the Aegean Sea, the Sea of Marmara, the Black Sea, the Caspian Sea, the Persian Gulf, the Gulf of Oman, the Arabian Sea, the Gulf of Aden, the Red Sea, the Gulf of Aqaba, the Gulf of Suez, and the Mediterranean Sea. West Asia contains the majority of the similarly defined Middle East. The ''Middle East'' is a political term invented by Western geographers that has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southeast Asia
Southeast Asia is the geographical United Nations geoscheme for Asia#South-eastern Asia, southeastern region of Asia, consisting of the regions that are situated south of China, east of the Indian subcontinent, and northwest of the Mainland Australia, Australian mainland, which is part of Oceania. Southeast Asia is bordered to the north by East Asia, to the west by South Asia and the Bay of Bengal, to the east by Oceania and the Pacific Ocean, and to the south by Australia (continent), Australia and the Indian Ocean. Apart from the British Indian Ocean Territory and two out of Atolls of the Maldives, 26 atolls of the Maldives in South Asia, Maritime Southeast Asia is the only other subregion of Asia that lies partly within the Southern Hemisphere. Mainland Southeast Asia is entirely in the Northern Hemisphere. Timor-Leste and the southern portion of Indonesia are the parts of Southeast Asia that lie south of the equator. The region lies near the intersection of Plate tectonics, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Asia
South Asia is the southern Subregion#Asia, subregion of Asia that is defined in both geographical and Ethnicity, ethnic-Culture, cultural terms. South Asia, with a population of 2.04 billion, contains a quarter (25%) of the world's population. As commonly conceptualised, the modern State (polity), states of South Asia include Bangladesh, Bhutan, India, the Maldives, Nepal, Pakistan, and Sri Lanka, with Afghanistan also often included, which may otherwise be classified as part of Central Asia. South Asia borders East Asia to the northeast, Central Asia to the northwest, West Asia to the west and Southeast Asia to the east. Apart from Southeast Asia, Littoral South Asia, Maritime South Asia is the only subregion of Asia that lies partly within the Southern Hemisphere. The British Indian Ocean Territory and two out of Atolls of Maldives, 26 atolls of the Maldives in South Asia lie entirely within the Southern Hemisphere. Topographically, it is dominated by the Indian subcontinent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanesia
Melanesia (, ) is a subregion of Oceania in the southwestern Pacific Ocean. It extends from New Guinea in the west to the Fiji Islands in the east, and includes the Arafura Sea. The region includes the four independent countries of Fiji, Vanuatu, Solomon Islands, and Papua New Guinea. It also includes the West New Guinea, Indonesian part of New Guinea, the French overseas collectivity of New Caledonia, and the Torres Strait Islands. Almost all of the region is in the Southern Hemisphere; only a few small islands that are not politically considered part of Oceania—specifically the northwestern islands of Western New Guinea—lie in the Northern Hemisphere. The name ''Melanesia'' (in French, ''Mélanésie'') was first used in 1832 by French navigator Jules Dumont d'Urville: he coined the terms ''Melanesia'' and ''Micronesia'' to go alongside the pre-existing ''Polynesia'' to designate what he viewed as the three main Ethnicity, ethnic and geographical regions forming the Pacif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australia
Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller islands. It has a total area of , making it the list of countries and dependencies by area, sixth-largest country in the world and the largest in Oceania. Australia is the world's flattest and driest inhabited continent. It is a megadiverse countries, megadiverse country, and its size gives it a wide variety of landscapes and Climate of Australia, climates including deserts of Australia, deserts in the Outback, interior and forests of Australia, tropical rainforests along the Eastern states of Australia, coast. The ancestors of Aboriginal Australians began arriving from south-east Asia 50,000 to 65,000 years ago, during the Last Glacial Period, last glacial period. By the time of British settlement, Aboriginal Australians spoke 250 distinct l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Africa
Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surface area.Sayre, April Pulley (1999), ''Africa'', Twenty-First Century Books. . With nearly billion people as of , it accounts for about of the world's human population. Demographics of Africa, Africa's population is the youngest among all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Based on 2024 projections, Africa's population will exceed 3.8 billion people by 2100. Africa is the least wealthy inhabited continent per capita and second-least wealthy by total wealth, ahead of Oceania. Scholars have attributed this to different factors including Geography of Africa, geography, Climate of Africa, climate, corruption, Scramble for Africa, colonialism, the Cold War, and neocolonialism. Despite this lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tropical
The tropics are the regions of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. This is because of Earth's axial tilt; the width of the tropics (in latitude) is twice the tilt. The tropics are also referred to as the tropical zone and the torrid zone (see geographical zone). Due to the overhead sun, the tropics receive the most solar energy over the course of the year, and consequently have the highest temperatures on the planet. Even when not directly overhead, the sun is still close to overhead throughout the year, therefore the tropics also have the lowest seasonal variation on the planet; "winter" and "summer" lose their temperature contrast. Instead, seasons are more commonly divided by precipitation variations than by temperature variations. The tropics maintain wide diversity of local climates, such as rain forests, monsoons, sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indigenous Tasmanians
The Aboriginal Tasmanians (palawa kani: ''Palawa'' or ''Pakana'') are the Aboriginal people of the Australian island of Tasmania, located south of the mainland. At the time of European contact, Aboriginal Tasmanians were divided into a number of distinct ethnic groups. For much of the 20th century, the Tasmanian Aboriginal people were widely, and erroneously, thought of as extinct and intentionally exterminated by white settlers. Contemporary figures (2016) for the number of people of Tasmanian Aboriginal descent vary according to the criteria used to determine this identity, ranging from 6,000 to over 23,000. First arriving in Tasmania (then a peninsula of Australia) around 40,000 years ago, the ancestors of the Aboriginal Tasmanians were cut off from the Australian mainland by rising sea levels 6000 BC. They were entirely isolated from the outside world for 8,000 years until European contact. Before British colonisation of Tasmania in 1803, there were an estimated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rickets
Rickets, scientific nomenclature: rachitis (from Greek , meaning 'in or of the spine'), is a condition that results in weak or soft bones in children and may have either dietary deficiency or genetic causes. Symptoms include bowed legs, stunted growth, bone pain, large forehead, and trouble sleeping. Complications may include bone Deformity, deformities, bone pseudofractures and Bone fracture, fractures, muscle spasms, or an scoliosis, abnormally curved spine. The analogous condition in adults is osteomalacia. The most common cause of rickets is a hypovitaminosis D, vitamin D deficiency, although hereditary genetic forms also exist. This can result from eating a diet without enough vitamin D, dark skin, too little sun exposure, exclusive breastfeeding without vitamin D supplementation, celiac disease, and certain genetic conditions. Other factors may include not enough calcium or phosphorus. The underlying mechanism involves insufficient calcification of the growth plate. Di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamin D Deficiency
Vitamin D deficiency or hypovitaminosis D is a vitamin D level that is below normal. It most commonly occurs in people when they have inadequate exposure to sunlight, particularly sunlight with adequate ultraviolet B rays (UVB). Vitamin D deficiency can also be caused by inadequate nutritional intake of vitamin D; disorders that limit vitamin D absorption; and disorders that impair the conversion of vitamin D to active metabolites, including certain liver, kidney, and hereditary disorders. Deficiency impairs bone mineralization, leading to bone-softening diseases, such as rickets in children. It can also worsen osteomalacia and osteoporosis in adults, increasing the risk of bone fractures. Muscle weakness is also a common symptom of vitamin D deficiency, further increasing the risk of falls and bone fractures in adults. Vitamin D deficiency is associated with the development of schizophrenia. Vitamin D can be synthesized in the skin under exposure to UVB from sunlight. Oily ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
