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Gigantopithecus
''Gigantopithecus'' ( ) is an extinct genus of ape that lived in southern China from 2 million to approximately 300,000–200,000 years ago during the Early Pleistocene, Early to Middle Pleistocene, represented by one species, ''Gigantopithecus blacki''. Potential identifications have also been made in Thailand, Vietnam, and Indonesia, but most of these were likely misidentified remains of the Chinese orangutan (''Pongo weidenreichi''). The first remains of ''Gigantopithecus'', two third molar teeth, were identified in a drugstore by anthropologist Ralph von Koenigswald in 1935, who subsequently species description, described the ape. In 1956, the first mandible and more than 1,000 teeth were found in Liucheng County, Liucheng, and numerous more remains have since been found in at least 16 sites. Only teeth and four mandibles are known currently, and other skeletal elements were likely consumed by Old World porcupine, porcupines before they could fossilise. ''Gigantopithecus'' was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ponginae
Ponginae , also known as the Asian hominids, is a subfamily in the family (biology), family Hominidae. Once a diverse lineage of Eurasian apes, the subfamily has only one Neontology, extant genus, ''Pongo (genus), Pongo'' (orangutans), which contains three extant species; the Sumatran orangutan (''Pongo abelii''), the Tapanuli orangutan (''Pongo tapanuliensis'') and the Bornean orangutan (''Pongo pygmaeus''). All three species are listed as critically endangered by the International Union for Conservation of Nature (IUCN). Evolutionary history The first pongine genera appear in the Miocene, ''Sivapithecus'' and ''Khoratpithecus'', six or seven million years before evidence of orangutans was found from Pleistocene southeast Asia and southern China. Ponginae may also include the genera ''Lufengpithecus'', ''Ankarapithecus'', and ''Gigantopithecus''. However, phylogenetic analysis in 2004, which originally found ''Lufengpithecus'' and ''Ankarapithecus'' to be most closely related to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chinese Orangutan
The Chinese orangutan (''Pongo weidenreichi'') is an extinct species of orangutan from the Pleistocene of South China and possibly Southeast Asia. It is known from fossil teeth found in the Sanhe Cave, and Baikong, Juyuan and Queque Caves in Chongzuo, Guangxi. Its dental dimensions are 20% bigger than those of living orangutans. The youngest remains of the species date to between 66,000-57,000 years ago in Yincun Cave, Guangxi. An isolated canine from Thẩm Khuyên Cave, Vietnam, and a fourth premolar from Pha Bong, Thailand, could possibly be assigned to ''Gigantopithecus'', though these could also represent ''Pongo weidenreichi''. Two possible teeth previously attributed to ''Gigantopithecus'' from the Late Pleistocene deposit from Vietnam has been subsequently suggested to represent ''P. weidenreichi'' instead. Palaeoecology ''P. weidenreichi'' had very similar dental microwear Dental microwear analysis is a method to infer diet and behavior in extinct animals, especially i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orangutan
Orangutans are great apes native to the rainforests of Indonesia and Malaysia. They are now found only in parts of Borneo and Sumatra, but during the Pleistocene they ranged throughout Southeast Asia and South China. Classified in the genus ''Pongo'', orangutans were originally considered to be one species. In 1996, they were divided into two species: the Bornean orangutan (''P. pygmaeus'', with three subspecies) and the Sumatran orangutan (''P. abelii''); a third species, the Tapanuli orangutan (''P. tapanuliensis''), was identified definitively in 2017. The orangutans are the only surviving members of the subfamily Ponginae, which diverged genetically from the other hominids (gorillas, chimpanzees, and humans) between 19.3 and 15.7 million years ago. The most arboreal of the great apes, orangutans spend most of their time in trees. They have proportionally long arms and short legs, and have reddish-brown hair covering their bodies. Adult males weigh about , while female ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene
The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek () 'most' and (; Latinized as ) 'new'. The aridification and cooling trends of the preceding Neogene were continued in the Pleistocene. The climate was strongly variable depending on the glacial cycle, oscillating between cold Glacial period, glacial periods and warmer Interglacial, int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liucheng County
Liucheng County (; Standard Zhuang: ) is under the administration of Liuzhou, Guangxi Zhuang Autonomous Region, China. It covers a land area of and had a permanent population of 353,796 . Located north of Liuzhou's city proper, it borders the prefecture-level city of Hechi Hechi ( zh, c=河池) is a prefecture-level city in the northwest of the Guangxi Zhuang Autonomous Region, People's Republic of China, bordering Guizhou to the north. The actual inner city itself is referred as Jinchengjiang ( zh, c=金城江). ... to the west. Administrative divisions Liucheng consists of 10 towns, 1 township and 1 ethnic township: ;Towns: Dapu (大埔镇), Longtou (龙头镇), Taiping (太平镇), Shapu (沙埔镇), Dongquan (东泉镇), Fengshan (凤山镇), Liutang (六塘镇), Chongyao (冲脉镇), Zhailong (寨隆镇), Mashan (马山镇) ;Township: Shechong Township (社冲乡) ;Ethnic township Guzhai Mulao Ethnic Township (古砦仫佬族乡) Climate References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C3 Carbon Fixation
carbon fixation is the most common of three metabolic pathways for carbon fixation in photosynthesis, the other two being and CAM. This process converts carbon dioxide and ribulose bisphosphate (RuBP, a 5-carbon sugar) into two molecules of 3-phosphoglycerate through the following reaction: :CO2 + H2O + RuBP → (2) 3-phosphoglycerate This reaction was first discovered by Melvin Calvin, Andrew Benson and James Bassham in 1950. C3 carbon fixation occurs in all plants as the first step of the Calvin–Benson cycle. (In and CAM plants, carbon dioxide is drawn out of malate and into this reaction rather than directly from the air.) Plants that survive solely on fixation ( plants) tend to thrive in areas where sunlight intensity is moderate, temperatures are moderate, carbon dioxide concentrations are around 200 ppm or higher, and groundwater is plentiful. The plants, originating during Mesozoic and Paleozoic eras, predate the plants and still represent approximatel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Generalist And Specialist Species
A generalist species is able to thrive in a wide variety of environmental conditions and can make use of a variety of different resources (for example, a heterotroph with a varied diet). A specialist species can thrive only in a narrow range of environmental conditions or has a limited diet. Most organisms do not all fit neatly into either group, however. Some species are highly specialized (the most extreme case being monophagous, eating one specific type of food), others less so, and some can tolerate many different environments. In other words, there is a continuum from highly specialized to broadly generalist species. Description Omnivores are usually generalists. Herbivores are often specialists, but those that eat a variety of plants may be considered generalists. A well-known example of a specialist animal is the monophagous koala, which subsists almost entirely on eucalyptus leaves. The raccoon is a generalist, because it has a natural range that includes most of Nor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tooth Enamel
Tooth enamel is one of the four major Tissue (biology), tissues that make up the tooth in humans and many animals, including some species of fish. It makes up the normally visible part of the tooth, covering the Crown (tooth), crown. The other major tissues are dentin, cementum, and Pulp (tooth), dental pulp. It is a very hard, white to off-white, highly mineralised substance that acts as a barrier to protect the tooth but can become susceptible to degradation, especially by acids from food and drink. In rare circumstances enamel fails to form, leaving the underlying dentin exposed on the surface. Features Enamel is the hardest substance in the human body and contains the highest percentage of minerals (at 96%),Ross ''et al.'', p. 485 with water and organic material composing the rest.Ten Cate's Oral Histology, Nancy, Elsevier, pp. 70–94 The primary mineral is hydroxyapatite, which is a crystalline calcium phosphate. Enamel is formed on the tooth while the tooth develops wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crown (tooth)
In dentistry, the crown is the visible part of the tooth above the gingival margin and is an essential component of dental anatomy. Covered by Tooth enamel, enamel, the crown plays a crucial role in cutting, tearing, and grinding food. Its shape and structure vary depending on the type and function of the tooth (incisors, Canine tooth, canines, premolars, or Molar (tooth), molars), and differ between Deciduous teeth, primary dentition and Permanent teeth, permanent dentition. The crown also contributes to facial aesthetics, speech, and oral health. Anatomical crown vs clinical crown The anatomical crown refers to the portion of the tooth covered by enamel, regardless of whether it is visible. The clinical crown is the part of the tooth that is visible in the mouth. In a healthy young adult, the gums typically follow the contour where enamel meets the root, so the clinical and anatomical crowns are similar in size. However, with age or periodontal disease, this may change. Te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Premolar
The premolars, also called premolar Tooth (human), teeth, or bicuspids, are transitional teeth located between the Canine tooth, canine and Molar (tooth), molar teeth. In humans, there are two premolars per dental terminology#Quadrant, quadrant in the permanent teeth, permanent set of teeth, making eight premolars total in the mouth. They have at least two Cusp (dentistry), cusps. Premolars can be considered transitional teeth during chewing, or mastication. They have properties of both the canines, that lie anterior and molars that lie Posterior (anatomy), posterior, and so food can be transferred from the canines to the premolars and finally to the molars for grinding, instead of directly from the canines to the molars. Human anatomy The premolars in humans are the maxillary first premolar, maxillary second premolar, mandibular first premolar, and the mandibular second premolar. Premolar teeth by definition are permanent teeth Anatomical terms of location#Proximal and distal, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cheek Teeth
Cheek teeth or postcanines comprise the molar and premolar teeth in mammals. Cheek teeth are multicuspidate (having many folds or tubercles). Mammals have multicuspidate molars (three in placentals, four in marsupials, in each jaw quadrant) and premolars situated between canines and molars whose shape and number varies considerably among particular groups. For example, many modern Carnivora possess carnassials, or secodont teeth. This scissor-like pairing of the last upper premolar and first lower molar is adapted for shearing meat. In contrast, the cheek teeth of deer and cattle are selenodont. Viewed from the side, these teeth have a series of triangular cusps or ridges, enabling the ruminants' sideways jaw motions to break down tough vegetable matter. Cheek teeth are sometimes separated from the incisors by a gap called a diastema. Cheek teeth in reptiles are much simpler as compared to mammals. Roles and significance Apart from helping grind the food to properly reduce th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Dimorphism
Sexual dimorphism is the condition where sexes of the same species exhibit different Morphology (biology), morphological characteristics, including characteristics not directly involved in reproduction. The condition occurs in most dioecy, dioecious species, which consist of most animals and some plants. Differences may include secondary sex characteristics, size, weight, color, markings, or behavioral or cognitive traits. Male-male reproductive competition has evolved a diverse array of sexually dimorphic traits. Aggressive utility traits such as "battle" teeth and blunt heads reinforced as battering rams are used as weapons in aggressive interactions between rivals. Passive displays such as ornamental feathering or song-calling have also evolved mainly through sexual selection. These differences may be subtle or exaggerated and may be subjected to sexual selection and natural selection. The opposite of dimorphism is ''monomorphism'', when both biological sexes are phenotype, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
