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Knuckle-walking
Knuckle-walking is a form of quadrupedal walking in which the forelimbs hold the fingers in a partially flexed posture that allows body weight to press down on the ground through the knuckles. Gorillas and chimpanzees use this style of locomotion, as do anteaters and platypuses. Knuckle-walking helps with actions other than locomotion on the ground. Gorillas use fingers for the manipulation of food, whereas chimpanzees use fingers for the manipulation of food and climbing. In anteaters and pangolins, the fingers have large claws for opening the mounds of social insects. Platypus fingers have webbing that extend past the fingers to aid in swimming, thus knuckle-walking is used to prevent stumbling. Gorillas move around by knuckle-walking, although they sometimes walk bipedally for short distances while carrying food or in defensive situations. Mountain gorillas use knuckle-walking plus other parts of their hand—fist-walking does not use the knuckles, using the backs of their h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giant Anteaters
The giant anteater (''Myrmecophaga tridactyla'') is an insectivorous mammal native to Central and South America. It is the largest of the four living species of anteaters, which are classified with sloths in the order Pilosa. The only extant member of the genus ''Myrmecophaga'', the giant anteater is mostly terrestrial, in contrast to other living anteaters and sloths, which are arboreal or semiarboreal. The species is in length, with weights of for males and for females. It is recognizable by its elongated snout, bushy tail, long foreclaws, and distinctively colored fur. The giant anteater is found in multiple habitats, including grassland and rainforest. It forages in open areas and rests in more forested habitats. It feeds primarily on ants and termites, using its foreclaws to dig them up and its long, sticky tongue to collect them. Though giant anteaters live in overlapping home ranges, they are mostly solitary except during mother-offspring relationships, aggressive in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australopithecus Anamensis
''Australopithecus anamensis'' is a hominin species that lived roughly between 4.3 and 3.8 million years ago, and is the oldest known ''Australopithecus'' species, Nearly 100 fossil specimens of ''A. anamensis'' are known from Kenya and Ethiopia, representing over 20 individuals. The first fossils of ''A. anamensis'' discovered are dated to around 3.8 and 4.2 million years ago and were found in Kanapoi and Allia Bay in northern Kenya. '' A. afarensis'' is normally accepted to have emerged within this lineage. However, ''A. anamensis'' and ''A. afarensis'' appear to have lived side-by-side for at least some period of time, and whether the lineage that led to extant humans emerged in ''A. afarensis'', or directly in ''A. anamensis'' is not fully settled. Fossil evidence determines that ''Australopithecus anamensis'' is the earliest hominin species in the Turkana Basin, but likely co-existed with ''afarensis'' towards the end of its existence. ''A. anamensis'' and ''A. afarensis'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elbow
The elbow is the region between the upper arm and the forearm that surrounds the elbow joint. The elbow includes prominent landmarks such as the olecranon, the cubital fossa (also called the chelidon, or the elbow pit), and the lateral and the medial epicondyles of the humerus. The elbow joint is a hinge joint between the arm and the forearm; more specifically between the humerus in the upper arm and the radius and ulna in the forearm which allows the forearm and hand to be moved towards and away from the body. The term ''elbow'' is specifically used for humans and other primates, and in other vertebrates it is not used. In those cases, forelimb plus joint is used. The name for the elbow in Latin is ''cubitus'', and so the word cubital is used in some elbow-related terms, as in ''cubital nodes'' for example. Structure Joint The elbow joint has three different portions surrounded by a common joint capsule. These are joints between the three bones of the elbow, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Western Lowland Gorilla
The western lowland gorilla (''Gorilla gorilla gorilla'') is one of two Critically Endangered subspecies of the western gorilla (''Gorilla gorilla'') that lives in Montane ecosystems#Montane forests, montane, Old-growth forest, primary and secondary forest, secondary forest and lowland swampland in central Africa in Angola (Cabinda Province), Cameroon, Central African Republic, Republic of the Congo, Democratic Republic of the Congo, Equatorial Guinea and Gabon. It is the nominate subspecies of the western gorilla, and the smallest of the four gorilla subspecies. The western lowland gorilla is the only subspecies kept in zoos with the exception of Amahoro (gorilla), Amahoro, a female eastern lowland gorilla at Antwerp Zoo, and a few mountain gorillas kept captive in the Democratic Republic of the Congo. Description The western lowland gorilla is the smallest subspecies of gorilla but still has exceptional size and strength. This species of gorillas exhibits pronounced sexual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kinematics
In physics, kinematics studies the geometrical aspects of motion of physical objects independent of forces that set them in motion. Constrained motion such as linked machine parts are also described as kinematics. Kinematics is concerned with systems of specification of objects' positions and velocities and mathematical transformations between such systems. These systems may be rectangular like Cartesian coordinate system, cartesian, Curvilinear coordinates like polar coordinates or other systems. The object trajectories may be specified with respect to other objects which may themselve be in motion relative to a standard reference. Rotating systems may also be used. Numerous practical problems in kinematics involve constraints, such as mechanical linkages, ropes, or rolling disks. Overview Kinematics is a subfield of physics and mathematics, developed in classical mechanics, that describes the motion of points, Physical object, bodies (objects), and systems of bodies (group ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giant Anteater Knuckle Walking
In folklore, giants (from Ancient Greek: ''gigas'', cognate giga-) are beings of humanoid appearance, but are at times prodigious in size and strength or bear an otherwise notable appearance. The word ''giant'' is first attested in 1297 from Robert of Gloucester's chronicle. It is derived from the ''Gigantes'' () of Greek mythology. Fairy tales such as ''Jack the Giant Killer'' have formed the modern perception of giants as dimwitted and violent ogres, sometimes said to eat humans, while other giants tend to eat livestock. In more recent portrayals, like those of Jonathan Swift and Roald Dahl, some giants are both intelligent and friendly. Literary and cultural analysis Giants appear many times in folklore and myths. Representing the human body enlarged to the point of being monstrous, giants evoke terror and remind humans of their body's frailty and mortality. They are often portrayed as monsters and antagonists, but there are exceptions. Some giants intermingle with human ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forearm
The forearm is the region of the upper limb between the elbow and the wrist. The term forearm is used in anatomy to distinguish it from the arm, a word which is used to describe the entire appendage of the upper limb, but which in anatomy, technically, means only the region of the upper arm, whereas the lower "arm" is called the forearm. It is homologous to the region of the leg that lies between the knee and the ankle joints, the crus. The forearm contains two long bones, the radius and the ulna, forming the two radioulnar joints. The interosseous membrane connects these bones. Ultimately, the forearm is covered by skin, the anterior surface usually being less hairy than the posterior surface. The forearm contains many muscles, including the flexors and extensors of the wrist, flexors and extensors of the digits, a flexor of the elbow ( brachioradialis), and pronators and supinators that turn the hand to face down or upwards, respectively. In cross-section, the forearm can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australopithecus Afarensis
''Australopithecus afarensis'' is an extinct species of australopithecine which lived from about 3.9–2.9 million years ago (mya) in the Pliocene of East Africa. The first fossils were discovered in the 1930s, but major fossil finds would not take place until the 1970s. From 1972 to 1977, the International Afar Research Expedition—led by anthropologists Maurice Taieb, Donald Johanson and Yves Coppens—unearthed several hundreds of hominin specimens in Hadar, Ethiopia, Hadar, Ethiopia, the most significant being the exceedingly well-preserved skeleton AL 288-1 ("Lucy (Australopithecus), Lucy") and the site AL 333 ("the First Family"). Beginning in 1974, Mary Leakey led an expedition into Laetoli, Tanzania, and notably recovered fossil trackways. In 1978, the species was first species description, described, but this was followed by arguments for splitting the wealth of specimens into different species given the wide range of variation which had been attributed to sexual dimorphi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baboon
Baboons are primates comprising the biology, genus ''Papio'', one of the 23 genera of Old World monkeys, in the family Cercopithecidae. There are six species of baboon: the hamadryas baboon, the Guinea baboon, the olive baboon, the yellow baboon, the Kinda baboon and the chacma baboon. Each species is native to one of six areas of Africa and the hamadryas baboon is also native to part of the Arabian Peninsula. Baboons are among the largest non-hominoid primates and have existed for at least two million years. Baboons vary in size and weight depending on the species. The smallest, the Kinda baboon, is in length and weighs only , while the largest, the chacma baboon, is up to in length and weighs . All baboons have long, dog-like muzzles, heavy, powerful jaws with sharp canine teeth, close-set eyes, thick fur except on their muzzles, short tails, and nerveless, hairless pads of skin on their protruding buttocks called callosity, ischial callosities that provide for sitting co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hamate
The hamate bone (from Latin language, Latin wiktionary:hamatus, hamatus, "hooked"), or unciform bone (from Latin language, Latin ''wikt:uncus, uncus'', "hook"), Latin os hamatum and occasionally abbreviated as just hamatum, is a bone in the human wrist readily distinguishable by its wedge shape and a hook-like process ("hamulus") projecting from its Radioulnar, palmar surface. Structure The hamate is an irregularly shaped carpal bone found within the hand. The hamate is found within the distal row of carpal bones, and abuts the metacarpals of the little finger and ring finger. Adjacent to the hamate on the ulnar side, and slightly proximal and ulnar to it, is the pisiform bone. Adjacent on the radial side is the capitate, and proximal is the lunate bone. Surfaces The hamate bone has six surfaces: * The ''superior'', the apex of the wedge, is narrow, convex, smooth, and articulates with the lunate bone, lunate. * The ''inferior'' articulates with the fourth and fifth metacarpal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capitate
The capitate bone is a bone in the human wrist found in the center of the carpal bone region, located at the distal end of the radius and ulna bones. It articulates with the third metacarpal bone (the middle finger) and forms the third carpometacarpal joint. The capitate bone is the largest of the carpal bones in the human hand. It presents, above, a rounded portion or head, which is received into the concavity formed by the scaphoid and lunate bones; a constricted portion or neck; and below this, the body.''Gray's Anatomy'' (1918). See infobox. The bone is also found in many other mammals, and is homologous with the "third distal carpal" of reptiles and amphibians. Structure The capitate is the largest carpal bone found within the hand. The capitate is found within the distal row of carpal bones. The capitate lies directly adjacent to the metacarpal of the ring finger on its distal surface, has the hamate on its ulnar surface and trapezoid on its radial surface, and abuts the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metacarpophalangeal Joint
The metacarpophalangeal joints (MCP) are situated between the metacarpal bones and the proximal phalanges of the fingers. These joints are of the condyloid kind, formed by the reception of the rounded heads of the metacarpal bones into shallow cavities on the proximal ends of the proximal phalanges. Being condyloid, they allow the movements of flexion, extension, abduction, adduction and circumduction (see anatomical terms of motion) at the joint. Structure Ligaments Each joint has: * palmar ligaments of metacarpophalangeal articulations * collateral ligaments of metacarpophalangeal articulations Dorsal surfaces The dorsal surfaces of these joints are covered by the expansions of the Extensor tendons, together with some loose areolar tissue which connects the deep surfaces of the tendons to the bones. Function The movements which occur in these joints are flexion, extension, adduction, abduction, and circumduction; the movements of abduction and adduction are very ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
