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Orthograde Posture
Orthograde is a term derived from Greek ὀρθός, ''orthos'' ("right", "true", "straight") + Latin ''gradi'' (to walk) that describes a manner of walking which is upright, with the independent motion of limbs. Both New and Old World monkeys are primarily arboreal, and they have a tendency to walk with their limbs swinging in parallel to one another. This differs from the manner of walking demonstrated by the apes. Chimpanzees, gorillas, orangutans and humans, when walking, walk upright, and their limbs swing in opposition to one another for balance (unlike monkeys, apes lack a tail to use for balance). Disadvantages related to upright walking do exist for primates, since their primary mode of locomotion is quadrupedalism. This upright locomotion is called "orthograde posture". Orthograde posture in humans was made possible through millions of years of evolution. In order to walk upright with maximum efficiency, the skull, spine, pelvis, lower limbs, and feet all underwent evo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propithecus Bipedal Gallop
A sifaka (; ) is a lemur of the genus ''Propithecus'' from the family Indriidae within the order Primates. The common name is an onomatopoeia of their characteristic "shi-fak" alarm call. Like all lemurs, they are found only on the island of Madagascar. All species of sifakas are threatened, ranging from endangered to critically endangered. Anatomy and physiology Sifakas are medium-sized indriids with a head and body length of and a weight of . Their tail is just as long as their body, which differentiates them from the Indri. Their fur is long and silky, with coloration varying by species from yellowish-white to blackish-brown. Their round, hairless face is always black. As with all lemurs, the sifaka has special adaptations for grooming, including a toilet-claw on its second toe and a toothcomb. Sifakas move by vertical clinging and leaping, meaning they maintain an upright position leaping from tree trunk to tree trunk and moving along branches. They are skillful cli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orrorin
''Orrorin'' is an extinct genus of primate within Homininae from the Miocene Lukeino Formation and Pliocene Mabaget Formation, both of Kenya. The type species is ''O. tugenenesis'', named in 2001, and a second species, ''O. praegens'', assigned to the genus in 2022. Discovery and naming ''Ororrin tugenensis'' The first part of the holotype, a lower molar, was discovered by Martin Pickford in 1974 and described by Pickford (1975). The team that found the rest of the holotype of ''O. tugenensis'' was led by Brigitte Senut and Martin Pickford from the French National Museum of Natural History. Starting from 17 October 2000, 20 fossils were found at four sites in the Lukeino Formation, Kenya: of these, the fossils at Cheboit and Aragai are the oldest (), while those in Kapsomin and Kapcheberek are found in the upper levels of the formation (). ''Orrorin tugenensis'' was named and described by Senut ''et al.'' (2001). ''Orrorin praegens'' The second species, ''O. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pronograde
Quadrupedalism is a form of locomotion in which animals have four legs that are used to bear weight and move around. An animal or machine that usually maintains a four-legged posture and moves using all four legs is said to be a quadruped (from Latin ''quattuor'' for "four", and ''pes'', ''pedis'' for "foot"). Quadruped animals are found among both vertebrates and invertebrates. Quadrupeds vs. tetrapods Although the words ‘quadruped’ and ‘tetrapod’ are both derived from terms meaning ‘four-footed’, they have distinct meanings. A tetrapod is any member of the taxonomic unit Tetrapoda (which is defined by descent from a specific four-limbed ancestor), whereas a quadruped actually uses four limbs for locomotion. Not all tetrapods are quadrupeds and not all quadrupedal animals are tetrapods; some arthropods are adapted for four-footed locomotion, such as the raptorial Mantodea, or mantises, and the Nymphalidae, or brush-footed butterflies—the largest butterfly f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bipedalism
Bipedalism is a form of terrestrial locomotion where an animal moves by means of its two rear (or lower) Limb (anatomy), limbs or legs. An animal or machine that usually moves in a bipedal manner is known as a biped , meaning 'two feet' (from Latin ''bis'' 'double' and ''pes'' 'foot'). Types of bipedal movement include walking or running (a bipedal gait) and jumping, hopping. Several groups of modern species are habitual bipeds whose normal method of locomotion is two-legged. In the Triassic period some groups of archosaurs (a group that includes crocodiles and dinosaurs) developed bipedalism; among the dinosaurs, all the early forms and many later groups were habitual or exclusive bipeds; the birds are members of a clade of exclusively bipedal dinosaurs, the theropods. Within mammals, habitual bipedalism has evolved multiple times, with the Macropodidae, macropods, Dipodomyinae, kangaroo rats and mice, springhare, Hopping mouse, hopping mice, pangolins and hominin apes (austr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lordosis
Lordosis is historically defined as an ''abnormal'' inward curvature of the lumbar spine. However, the terms ''lordosis'' and ''lordotic'' are also used to refer to the normal inward curvature of the lumbar and cervical vertebrae, cervical regions of the human vertebral column, spine. Similarly, kyphosis historically refers to ''abnormal'' convex curvature of the spine. The normal outward (convex) curvature in the thoracic and sacrum, sacral regions is also termed ''kyphosis'' or ''kyphotic''. The term comes . Lordosis in the human vertebral column, human spine makes it easier for humans to bring the bulk of their mass over the pelvis. This allows for a much more efficient walking Gait (human), gait than that of other primates, whose inflexible spines cause them to resort to an inefficient forward-leaning "bent-knee, bent-waist" gait. As such, lordosis in the human spine is considered one of the primary physiological adaptations of the human skeleton that allows for human gait ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thoracic Vertebrae
In vertebrates, thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. In humans, there are twelve thoracic vertebra (anatomy), vertebrae of intermediate size between the cervical and lumbar vertebrae; they increase in size going towards the lumbar vertebrae. They are distinguished by the presence of Zygapophysial joint, facets on the sides of the bodies for Articulation (anatomy), articulation with the head of rib, heads of the ribs, as well as facets on the transverse processes of all, except the eleventh and twelfth, for articulation with the tubercle (rib), tubercles of the ribs. By convention, the human thoracic vertebrae are numbered T1–T12, with the first one (T1) located closest to the skull and the others going down the spine toward the lumbar region. General characteristics These are the general characteristics of the second through eighth thoracic vertebrae. The first and ninth through twelfth v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encephalization Quotient
Encephalization quotient (EQ), encephalization level (EL), or just encephalization is a relative brain size measure that is defined as the ratio between observed and predicted brain mass for an animal of a given size, based on nonlinear regression on a range of reference species. It has been used as a proxy for intelligence and thus as a possible way of comparing the intelligence levels of different species. For this purpose, it is a more refined measurement than the raw brain-to-body mass ratio, as it takes into account allometric effects. Expressed as a formula, the relationship has been developed for mammals and may not yield relevant results when applied outside this group. Perspective on intelligence measures Encephalization quotient was developed in an attempt to provide a way of correlating an animal's physical characteristics with perceived intelligence. It improved on the previous attempt, brain-to-body mass ratio, so it has persisted. Subsequent work, notably R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taung Child
The Taung Child (or Taung Baby) is the fossilised skull of a young ''Australopithecus africanus''. It was discovered in 1924 by quarrymen working for the Northern Lime Company in Taung, South Africa. Raymond Dart described it as a new species in the journal ''Nature'' in 1925. The Taung skull is in repository at the University of Witwatersrand. Dean Falk, a specialist in brain evolution, has called it "the most important anthropological fossil of the twentieth century." Description The Taung Child was originally thought to have been about six years old at death because of the presence of deciduous teeth, but is now believed to have been about three or four, based on studies of rates of enamel deposition on the teeth. There was some debate over the age of the child, initially because it was unclear if they grew at the speed of a human, or of an ape. Compared to an ape, they would have been aged about 4 years, and compared to a human, they would have been aged around 5–7 y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rib Cage
The rib cage or thoracic cage is an endoskeletal enclosure in the thorax of most vertebrates that comprises the ribs, vertebral column and sternum, which protect the vital organs of the thoracic cavity, such as the heart, lungs and great vessels and support the shoulder girdle to form the core part of the axial skeleton. A typical human thoracic cage consists of 12 pairs of ribs and the adjoining costal cartilages, the sternum (along with the manubrium and xiphoid process), and the 12 thoracic vertebrae articulating with the ribs. The thoracic cage also provides attachments for extrinsic skeletal muscles of the neck, upper limbs, upper abdomen and back, and together with the overlying skin and associated fascia and muscles, makes up the thoracic wall. In tetrapods, the rib cage intrinsically holds the muscles of respiration ( diaphragm, intercostal muscles, etc.) that are crucial for active inhalation and forced exhalation, and therefore has a major ventilatory fu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shoulder Joint
The shoulder joint (or glenohumeral joint from Greek ''glene'', eyeball, + -''oid'', 'form of', + Latin ''humerus'', shoulder) is structurally classified as a synovial joint, synovial ball-and-socket joint and functionally as a diarthrosis and multiaxial joint. It involves an articulation between the glenoid fossa of the scapula (shoulder blade) and the head of the humerus (upper arm bone). Due to the very loose joint capsule, it gives a limited interface of the humerus and scapula, it is the most mobile joint of the human body. Structure The shoulder joint is a ball-and-socket joint between the scapula and the humerus. The socket of the glenoid fossa of the scapula is itself quite shallow, but it is made deeper by the addition of the glenoid labrum. The glenoid labrum is a ring of cartilage, cartilaginous fibre attached to the circumference of the cavity. This ring is continuous with the tendon of the Biceps, biceps brachii above. Spaces Significant joint spaces are: * The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hominini
The Hominini (hominins) form a Tribe (biology), taxonomic tribe of the subfamily Homininae (hominines). They comprise two extant genera: ''Homo'' (humans) and ''Pan (genus), Pan'' (chimpanzees and bonobos), and in standard usage exclude the genus ''Gorilla (genus), Gorilla'' (gorillas), which is grouped separately within the subfamily Homininae. The term Hominini was originally introduced by Camille Arambourg (1948), who combined the categories of ''Hominina'' and ''Simiina'' pursuant to John Edward Gray, Gray's classifications (1825). Traditionally, chimpanzees, gorillas and orangutans were grouped together, excluding humans, as pongidae, pongids. Since Gray's classifications, evidence accumulating from genetic phylogeny confirmed that humans, chimpanzees, and gorillas are more closely related to each other than to the orangutan. The orangutans were reassigned to the family Hominidae (great apes), which already included humans; and the gorillas were grouped as a separate tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ardipithecus
''Ardipithecus'' is a genus of an extinct hominine that lived during the Late Miocene and Early Pliocene epochs in the Afar Depression, Ethiopia. Originally described as one of the earliest ancestors of humans after they diverged from the chimpanzees, the relation of this genus to human ancestors and whether it is a hominin is now a matter of debate. Two fossil species are described in the literature: '' A. ramidus'', which lived about 4.4 million years ago during the early Pliocene, and '' A. kadabba'', dated to approximately 5.6 million years ago (late Miocene). Initial behavioral analysis indicated that ''Ardipithecus'' could be very similar to chimpanzees; however, more recent analysis based on canine size and lack of canine sexual dimorphism indicates that ''Ardipithecus'' was characterised by reduced aggression, and that they more closely resemble bonobos. Some analyses describe ''Australopithecus'' as being sister to ''Ardipithecus ramidus'' specifically. This ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
