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Chin
The chin is the forward pointed part of the anterior mandible (List_of_human_anatomical_regions#Regions, mental region) below the lower lip. A fully developed human skull has a chin of between 0.7 cm and 1.1 cm. Evolution The presence of a well-developed chin is considered to be one of the morphological characteristics of ''Homo sapiens'' that Neanderthal anatomy#Distinguishing physical traits, differentiates them from other human ancestors such as the closely related Neanderthal, Neanderthals. Early human ancestors have varied Mandibular symphysis, symphysial morphology, but none of them have a well-developed chin. The origin of the chin is traditionally associated with the anterior–posterior breadth shortening of the dental arch or tooth row; however, its general mechanical or functional advantage during feeding, developmental origin, and link with human speech, physiology, and social influence are highly debated. Functional perspectives Robinson (1913) suggests that the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primate
Primates is an order (biology), order of mammals, which is further divided into the Strepsirrhini, strepsirrhines, which include lemurs, galagos, and Lorisidae, lorisids; and the Haplorhini, haplorhines, which include Tarsiiformes, tarsiers and simians (monkeys and apes). Primates arose 74–63 million years ago first from small terrestrial animal, terrestrial mammals, which adapted for life in tropical forests: many primate characteristics represent adaptations to the challenging environment among Canopy (biology), tree tops, including large brain sizes, binocular vision, color vision, Animal communication, vocalizations, shoulder girdles allowing a large degree of movement in the upper limbs, and opposable thumbs (in most but not all) that enable better grasping and dexterity. Primates range in size from Madame Berthe's mouse lemur, which weighs , to the eastern gorilla, weighing over . There are 376–524 species of living primates, depending on which classification is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimple
A dimple, also called a gelasin (, ), and a fovea buccalis, is a small natural indentation in the flesh on a part of the human body, most notably in the cheek. Numerous cultures believe that cheek dimples are a good luck charm that entices people who perceive them as physically attractive, but they are also associated with heroism and innocence, which has been included in literature for many centuries. Medical research debates whether cheek dimples can be inherited or which type of allele they are, but it is certain that humans with cheek dimples are more likely to have them in both cheeks. Depth and length appearances are affected by the shape of the skull and dimples can appear and disappear due to age. There are four types of facial dimples, including cheek, and the cleft chin (sometimes nicknamed a "chin dimple"). Overview Cheek dimples when present, show up when a person makes a facial expression, such as smiling, whereas a chin dimple is a small line on the chin that stay ... [...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] |
Neanderthal Anatomy
Neanderthal anatomy is characterised by a long, flat skull and a stocky body plan. When first discovered, Neanderthals were thought to be anatomically comparable to Aboriginal Australians, in accord with historical race concepts. As more fossils were discovered in the early 20th century, French palaeontologist Marcellin Boule defined them as a slouching, apelike species; a popular image until the middle of the century. Neanderthal features gradually accreted in European populations over the Chibanian, Middle Pleistocene, driven by natural selection in a cold climate, as well as genetic drift when populations crashed during glacial periods. This culminated in the "classical Neanderthal" anatomy by the Last Interglacial. The Neanderthal skull is distinctive by namely a rounded supraorbital torus (brow ridge), large orbit (anatomy), orbits (eye sockets) and nose, and an occipital bun at the back of the skull. The jaws and teeth are strong, which may have been a response to habitual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mandible
In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone is the skull's only movable, posable bone, sharing Temporomandibular joint, joints with the cranium's temporal bones. The mandible hosts the lower Human tooth, teeth (their depth delineated by the alveolar process). Many muscles attach to the bone, which also hosts nerves (some connecting to the teeth) and blood vessels. Amongst other functions, the jawbone is essential for chewing food. Owing to the Neolithic Revolution, Neolithic advent of agriculture (), human jaws evolved to be Human jaw shrinkage, smaller. Although it is the strongest bone of the facial skeleton, the mandible tends to deform in old age; it is also subject to Mandibular fracture, fracturing. Surgery allows for the removal of jawbone fragments (or its entirety) as well a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neanderthal
Neanderthals ( ; ''Homo neanderthalensis'' or sometimes ''H. sapiens neanderthalensis'') are an extinction, extinct group of archaic humans who inhabited Europe and Western and Central Asia during the Middle Pleistocene, Middle to Late Pleistocene. Neanderthal extinction occurred roughly 40,000 years ago with the immigration of modern humans (Cro-Magnons), but Neanderthals in Gibraltar may have persisted for thousands of years longer. The first recognised Neanderthal fossil, Neanderthal 1, was discovered in 1856 in the Neander Valley, Germany. At first, Neanderthal 1 was considered to be one of the racial hierarchy, lower races in accord with historical race concepts. As more fossils were discovered through the early 20th century, Neanderthals became characterised most especially by Marcellin Boule as a unique species of underdeveloped human. By the mid-20th century, human evolution was described as progressing from an apelike ancestor, through a "Neanderthal phase", ending ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mastication
Chewing or mastication is the process by which food is comminution, crushed and ground by the teeth. It is the first step in the process of digestion, allowing a greater surface area for digestive enzymes to break down the foods. During the mastication process, the food is positioned by the cheek and tongue between the teeth for grinding. The muscles of mastication move the jaws to bring the teeth into intermittent contact, repeatedly occlusion (dentistry), occluding and opening. As chewing continues, the food is made softer and warmer, and the enzymes in saliva begin to break down carbohydrates in the food. After chewing, the food (now called a Bolus (digestion), bolus) is swallowed. It enters the esophagus and via peristalsis continues on to the stomach, where the next step of digestion occurs. Increasing the number of chews per bite stimulates the production of digestive enzymes and peptides and has been shown to increase diet-induced thermogenesis (DIT) by activating the sympa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adaptation
In biology, adaptation has three related meanings. Firstly, it is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. Secondly, it is a state reached by the population during that process. Thirdly, it is a phenotypic trait or adaptive trait, with a functional role in each individual organism, that is maintained and has evolved through natural selection. Historically, adaptation has been described from the time of the ancient Greek philosophers such as Empedocles and Aristotle. In 18th and 19th-century natural theology, adaptation was taken as evidence for the existence of a deity. Charles Darwin and Alfred Russel Wallace proposed instead that it was explained by natural selection. Adaptation is related to biological fitness, which governs the rate of evolution as measured by changes in allele frequencies. Often, two or more species co-adapt and co-evolve as they develop adaptations tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hunter-gatherer
A hunter-gatherer or forager is a human living in a community, or according to an ancestrally derived Lifestyle, lifestyle, in which most or all food is obtained by foraging, that is, by gathering food from local naturally occurring sources, especially wild edible plants but also insects, Fungus, fungi, Honey hunting, honey, Eggs as food, bird eggs, or anything safe to eat, or by hunting game (pursuing or trapping and killing Wildlife, wild animals, including Fishing, catching fish). This is a common practice among most vertebrates that are omnivores. Hunter-gatherer Society, societies stand in contrast to the more Sedentism, sedentary Agrarian society, agricultural societies, which rely mainly on cultivating crops and raising domesticated animals for food production, although the boundaries between the two ways of living are not completely distinct. Hunting and gathering was humanity's original and most enduring successful Competition (biology), competitive adaptation in the nat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alveolar Process
The alveolar process () is the portion of bone containing the tooth sockets on the jaw bones (in humans, the maxilla and the mandible). The alveolar process is covered by gums within the mouth, terminating roughly along the line of the mandibular canal. Partially comprising compact bone, it is penetrated by many small openings for blood vessels and connective fibres. The bone is of clinical, phonetic and forensic significance. Terminology The term ''alveolar'' () ('hollow') refers to the cavities of the tooth sockets, known as dental alveoli. The alveolar process is also called the ''alveolar bone'' or ''alveolar ridge''. In phonetics, the term refers more specifically to the ridges on the inside of the mouth which can be felt with the tongue, either on roof of the mouth between the upper teeth and the hard palate or on the bottom of the mouth behind the lower teeth. The curved portion of the process is referred to as the alveolar arch. The alveolar bone proper, also ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyoid Bone
The hyoid-bone (lingual-bone or tongue-bone) () is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid-cartilage. At rest, it lies between the base of the mandible and the third cervical vertebra. Unlike other bones, the hyoid is only distantly articulated to other bones by muscles or ligaments. It is the only bone in the human body that is not connected to any other bones. The hyoid is anchored by muscles from the anterior, posterior and inferior directions, and aids in tongue movement and swallowing. The hyoid bone provides attachment to the muscles of the floor of the mouth and the tongue above, the larynx below, and the epiglottis and pharynx behind. Its name is derived . Structure The hyoid bone is classed as an irregular bone and consists of a central part called the body, and two pairs of horns, the greater and lesser horns. Body The body of the hyoid bone is the central part of the hyoid bone. *At the fron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
