|
Homo Luzonensis
''Homo luzonensis'', also locally called "Ubag" after a mythical caveman, is an extinct, possibly pygmy, species of archaic human from the Late Pleistocene of Luzon, the Philippines. Their remains, teeth and phalanges, are known only from Callao Cave in the northern part of the island dating to before 50,000 years ago. They were initially identified as belonging to modern humans in 2010, but in 2019, after the discovery of more specimens, they were placed into a new species based on the presence of a wide range of traits similar to modern humans as well as to ''Australopithecus'' and early ''Homo''. Their ancestors, who may have been Asian ''H. erectus'' or some other even earlier ''Homo'', would have needed to have made a sea crossing of several miles at minimum to reach the island. Human presence on Luzon dates to at latest 771,000 to 631,000 years ago. The inhabitants of the cave dragged in mainly Philippine deer carcasses, and used tools for butchering. Taxonomy The first r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Pleistocene
The Late Pleistocene is an unofficial Age (geology), age in the international geologic timescale in chronostratigraphy, also known as Upper Pleistocene from a Stratigraphy, stratigraphic perspective. It is intended to be the fourth division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently defined as the time between c. 129,000 and c. 11,700 years ago. The Late Pleistocene equates to the proposed Tarantian Age of the geologic time scale, preceded by the officially ratified Chibanian (formerly known as Middle Pleistocene) and succeeded by the officially ratified Greenlandian. The estimated beginning of the Tarantian is the start of the Eemian interglacial period (Marine Isotope Stage 5). It is held to end with the termination of the Younger Dryas, some 10th millennium BC, 11,700 years ago when the Holocene Epoch began. The term Upper Pleistocene is currently in use as a provisional or "quasi-formal" designation by the International Union of Geological ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Femur
The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates with the tibia (shinbone) and patella (kneecap), forming the knee joint. By most measures the two (left and right) femurs are the strongest bones of the body, and in humans, the largest and thickest. Structure The femur is the only bone in the upper leg. The two femurs converge medially toward the knees, where they articulate with the proximal ends of the tibiae. The angle of convergence of the femora is a major factor in determining the femoral-tibial angle. Human females have thicker pelvic bones, causing their femora to converge more than in males. In the condition ''genu valgum'' (knock knee) the femurs converge so much that the knees touch one another. The opposite extreme is ''genu varum'' (bow-leggedness). In the general populatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australopithecus Africanus
''Australopithecus africanus'' is an extinct species of australopithecine which lived between about 3.3 and 2.1 million years ago in the Late Pliocene to Early Pleistocene of South Africa. The species has been recovered from Taung, Sterkfontein, Makapansgat, and Gladysvale. The first specimen, the Taung child, was described by anatomist Raymond Dart in 1924, and was the first early hominin found. However, its closer relations to humans than to other apes would not become widely accepted until the middle of the century because most had believed humans evolved outside of Africa. It is unclear how ''A. africanus'' relates to other hominins, being variously placed as ancestral to ''Homo'' and '' Paranthropus'', to just ''Paranthropus'', or to just '' P. robustus''. The specimen "Little Foot" is the most completely preserved early hominin, with 90% of the skeleton intact, and the oldest South African australopith. However, it is controversially suggested that it and similar speci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homo Habilis
''Homo habilis'' ("handy man") is an extinct species of archaic human from the Early Pleistocene of East and South Africa about 2.31 million years ago to 1.65 million years ago (mya). Upon species description in 1964, ''H. habilis'' was highly contested, with many researchers recommending it be synonymised with '' Australopithecus africanus'', the only other early hominin known at the time, but ''H. habilis'' received more recognition as time went on and more relevant discoveries were made. By the 1980s, ''H. habilis'' was proposed to have been a human ancestor, directly evolving into '' Homo erectus'' which directly led to modern humans. This viewpoint is now debated. Several specimens with insecure species identification were assigned to ''H. habilis'', leading to arguments for splitting, namely into "''H. rudolfensis''" and "'' H. gautengensis''" of which only the former has received wide support. Like contemporary ''Homo'', ''H. habilis'' brain size generally varied from . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscles Of The Hand
The muscles of the hand are the skeletal muscles responsible for the movement of the hand and fingers. The muscles of the hand can be subdivided into two groups: the extrinsic and intrinsic muscle groups. The extrinsic muscle groups are the long flexors and extensors. They are called extrinsic because the muscle belly is located on the forearm. The intrinsic group are the smaller muscles located within the hand itself. The muscles of the hand are innervated by the radial, median, and ulnar nerves from the brachial plexus. Intrinsic The intrinsic muscle groups are the thenar (thumb) and hypothenar (little finger) muscles; the interossei muscles ( four dorsally and three volarly) originating between the metacarpal bones; and the lumbrical muscles arising from the deep flexor (and which are special because they have no bony origin) to insert on the dorsal extensor hood mechanism. Palmaris brevis which is a superficial muscle and adductor pollicis are also intrinsic muscles. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anatomical Terms Of Location
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabularies for subdisciplines of anatom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paranthropus
''Paranthropus'' is a genus of extinct hominin which contains two widely accepted species: ''Paranthropus robustus, P. robustus'' and ''P. boisei''. However, the validity of ''Paranthropus'' is contested, and it is sometimes considered to be synonym (taxonomy), synonymous with ''Australopithecus''. They are also referred to as the robust australopithecines. They lived between approximately 2.6 and 1.2 million years ago (mya) from the end of the Pliocene to the Middle Pleistocene. ''Paranthropus'' is characterised by Robustness (morphology), robust skulls, with a prominent gorilla-like sagittal crest along the midline—which suggest strong chewing muscles—and broad, herbivorous teeth used for grinding. However, they likely preferred soft food over tough and hard food. ''Paranthropus'' species were generalist feeders, but ''P. robustus'' was likely an omnivore, whereas ''P. boisei'' was likely herbivorous and mainly ate bulbotubers. They were bipeds. Despite their robust heads, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dentin
Dentin () (American English) or dentine ( or ) (British English) ( la, substantia eburnea) is a calcified tissue of the body and, along with enamel, cementum, and pulp, is one of the four major components of teeth. It is usually covered by enamel on the crown and cementum on the root and surrounds the entire pulp. By volume, 45% of dentin consists of the mineral hydroxyapatite, 33% is organic material, and 22% is water. Yellow in appearance, it greatly affects the color of a tooth due to the translucency of enamel. Dentin, which is less mineralized and less brittle than enamel, is necessary for the support of enamel. Dentin rates approximately 3 on the Mohs scale of mineral hardness. There are two main characteristics which distinguish dentin from enamel: firstly, dentin forms throughout life; secondly, dentin is sensitive and can become hypersensitive to changes in temperature due to the sensory function of odontoblasts, especially when enamel recedes and dentin channels becom ... [...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 other 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. Calcium hardens the tooth enamel. 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 o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insular Dwarfism
Insular dwarfism, a form of phyletic dwarfism, is the process and condition of large animals evolving or having a reduced body size when their population's range is limited to a small environment, primarily islands. This natural process is distinct from the intentional creation of dwarf breeds, called dwarfing. This process has occurred many times throughout evolutionary history, with examples including dinosaurs, like '' Europasaurus'' and ''Magyarosaurus dacus'', and modern animals such as elephants and their relatives. This process, and other "island genetics" artifacts, can occur not only on islands, but also in other situations where an ecosystem is isolated from external resources and breeding. This can include caves, desert oases, isolated valleys and isolated mountains ("sky islands"). Insular dwarfism is one aspect of the more general "island effect" or "Foster's rule", which posits that when mainland animals colonize islands, small species tend to evolve larger bodies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemic
Endemism is the state of a species being found 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 be also be referred to as an ''endemism'' or in scientific literature as an ''endemite''. For example '' Cytisus aeolicus'' is an endemite of the Italian flora. '' Adzharia renschi'' was once believed to be an endemite of the Caucasus, but it was later discovered to be a non-indigenous species from South America belonging to a different genus. The extreme opposite of an endemic species is one with a cosmopolitan distribution, having a global or widespread range. A rare alternative term for a species that is endemic is "precinctive", which applies to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homo Luzonensis Teeth And Foot Bones Diagram
''Homo'' () is the genus that emerged in the (otherwise extinct) genus ''Australopithecus'' that encompasses the extant species ''Homo sapiens'' (modern humans), plus several extinct species classified as either ancestral to or closely related to modern humans (depending on the species), most notably ''Homo erectus'' and ''Homo neanderthalensis''. The genus emerged with the appearance of ''Homo habilis'' just over 2 million years ago. ''Homo'', together with the genus ''Paranthropus'', is probably sister to ''Australopithecus africanus'', which itself had previously split from the lineage of '' Pan'', the chimpanzees. ''Homo erectus'' appeared about 2 million years ago and, in several early migrations, spread throughout Africa (where it is dubbed ''Homo ergaster'') and Eurasia. It was likely that the first human species lived in a hunter-gatherer society and was able to control fire. An adaptive and successful species, ''Homo erectus'' persisted for more than a million years ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.PNG "Click for more on -> Muscles Of The Hand")
.jpg "Click for more on -> Endemic")
