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Obturator Externus Groove
The obturator externus groove is the groove on the posterior neck of the femur for the insertion of the obturator externus muscle, a muscle that is important during bipedal locomotion. It is located within the depression of the trochanteric fossa. This landmark is used as evidence of bipedal locomotion in the hominins. The fossil '' Orrorin tugenensis'' (6-7 mya) possesses the obturator externus The external obturator muscle or obturator externus muscle (; OE) is a flat, triangular muscle, which covers the outer surface of the anterior wall of the pelvis. It is sometimes considered part of the medial compartment of thigh, and sometime ... groove, which suggests that it moved bipedally and could represent one of the earliest fossils with evidence of bipedal locomotion. References Bones of the lower limb {{musculoskeletal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Femur
The femur (; : femurs or femora ), or thigh bone is the only long bone, bone in the thigh — the region of the lower limb between the hip and the knee. In many quadrupeds, four-legged animals the femur is the upper bone of the hindleg. The Femoral head, top of the femur fits into a socket in the pelvis called the hip joint, and the bottom of the femur connects to the shinbone (tibia) and kneecap (patella) to form the knee. In humans the femur is the largest and thickest bone in the body. Structure The femur is the only bone in the upper Human leg, leg. The two femurs converge Anatomical terms of location, medially toward the knees, where they articulate with the Anatomical terms of location, proximal ends of the tibiae. The angle at which the femora converge is an important factor in determining the femoral-tibial angle. In females, thicker pelvic bones cause the femora to converge more than in males. In the condition genu valgum, ''genu valgum'' (knock knee), the femurs conve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Obturator Externus
The external obturator muscle or obturator externus muscle (; OE) is a flat, triangular muscle, which covers the outer surface of the anterior wall of the pelvis. It is sometimes considered part of the medial compartment of thigh, and sometimes considered part of the gluteal region. It is also considered to be part of the short external rotators of the hip, along with the gemellus superior and inferior, piriformis, and quadratus femoris. Structure It arises from the margin of bone immediately around the medial side of the obturator membrane and surrounding bone, viz., from the inferior pubic ramus, and the ramus of the ischium; it also arises from the medial two-thirds of the outer surface of the obturator membrane, and from the tendinous arch which completes the canal for the passage of the obturator vessels and nerves. The fibers springing from the pubic arch extend on to the inner surface of the bone, where they obtain a narrow origin between the margin of the for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trochanteric Fossa
In mammals including humans, the medial surface of the greater trochanter has at its base a deep depression bounded posteriorly by the intertrochanteric crest, called the trochanteric fossa. This fossa is the point of insertion of four muscles. Moving from the inferior-most to the superior-most, they are: the tendon of the obturator externus muscle, the obturator internus, the superior gemellus and inferior gemellus. The width and depth of the trochanteric fossa varies taxonomically.Gray's AnatomyNetter 2003Romer 1956 In reptiliomorphs such as Seymouria or Diadectes and basal reptiles such as Pareiasaurus, the trochanteric fossa (also known as the intertrochanteric fossa) is a very large depression on the ventral/posterior side of the femur. It is bounded medially by the internal trochanter (also known as the lesser trochanter), laterally by the posterior branch of the ventral ridge, and inferiorly by the convergence of the anterior and posterior branches of the ventral ridge a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bipedal
Bipedalism is a form of terrestrial locomotion where an animal moves by means of its two rear (or lower) 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 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 macropods, kangaroo rats and mice, springhare, hopping mice, pangolins and hominin apes ( australopithecines, including humans) as well as various ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hominin
The Hominini (hominins) form a taxonomic tribe of the subfamily Homininae (hominines). They comprise two extant genera: ''Homo'' (humans) and '' Pan'' (chimpanzees and bonobos), and in standard usage exclude the 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 Gray's classifications (1825). Traditionally, chimpanzees, gorillas and orangutans were grouped together, excluding humans, as 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 tribe (Gorillini) of the subfamily Homininae. Still, details of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orrorin Tugenensis
''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] |
