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Fukuipteryx
''Fukuipteryx'' is an extinct genus of basal avialan dinosaurs found in Early Cretaceous deposits from Japan's Kitadani Formation. It contains one species, ''Fukuipteryx prima''.Imai, T., Azuma, Y., Kawabe, S., Shibata, M., Miyata, K., Wang, M., & Zhou, Z. (2019)An unusual bird (Theropoda, Avialae) from the Early Cretaceous of Japan suggests complex evolutionary history of basal birds Communications Biology, 2(1). doi: 10.1038/s42003-019-0639-4 Discovery and naming In 2013, the first associated skeleton of an Early Cretaceous avialan from Japan was collected at the Kitadani Dinosaur Quarry in Katsuyama, Fukui, Katsuyama, Fukui Prefecture, Fukui, central Japan. The specimen is three-dimensionally preserved, and exhibits several autapomorphies, which led to the creation of a new taxon. In 2019, the type species ''Fukuipteryx prima'' was named and described by Takuya Imai, Yoichi Azuma, Soichiro Kawabe, Masateru Shibata, Kazunori Miyata, Wang Min and Zhou Zhonghe. The genus name c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fukui Prefectural Dinosaur Museum
The , located in Katsuyama, Fukui, Japan, is one of the leading dinosaur museums in Asia that is renowned for its exhibits of fossil specimens of dinosaurs and paleontological research. It is sited in the Nagaoyama Park ( Katsuyama Dinosaur Forest Park) near the Kitadani Dinosaur Quarry that the Lower Cretaceous Kitadani Formation of the Tetori Group is cropped out and a large number of dinosaur remains including ''Fukuiraptor kitadaniensis'' and ''Fukuisaurus tetoriensis'' are found and excavated. Since October 2009, the entire area of Katsuyama City has been recognized as a Japanese Geopark "". Since July 2014, the guide tour to the field station next to the excavation site has been available from the end of April to early November. Dozens of fossil specimens of five named dinosaurs and their excavation site have been designated as a Natural Monument of Japan since February 2017. The Asia Dinosaur Association Secretary Office has been housed inside the museum since its esta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avialan
Avialae ("bird wings") is a clade containing the only living dinosaurs, the birds. It is usually defined as all theropod dinosaurs more closely related to birds (Aves) than to deinonychosaurs, though alternative definitions are occasionally used (see below). ''Archaeopteryx lithographica'', from the late Jurassic Period Solnhofen Formation of Germany, is possibly the earliest known avialan which may have had the capability of powered flight, though it might have been a deinonychosaur instead. Several older (but non flight-capable) avialans are known from the late Jurassic Tiaojishan Formation of China, dated to about 160 million years ago. Definition Most researchers define Avialae as branch-based clade, though definitions vary. Many authors have used a definition similar to "all theropods closer to birds than to ''Deinonychus''."Weishampel, David B.; Dodson, Peter; Osmólska, Halszka (eds.) (2004). ''The Dinosauria'', Second Edition. University of California Press., 861 pp. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avialae
Avialae ("bird wings") is a clade containing the only living dinosaurs, the birds. It is usually defined as all theropod dinosaurs more closely related to birds (Aves) than to deinonychosaurs, though alternative definitions are occasionally used (see below). ''Archaeopteryx lithographica'', from the late Jurassic Period Solnhofen Formation of Germany, is possibly the earliest known avialan which may have had the capability of powered flight, though it might have been a deinonychosaur instead. Several older (but non flight-capable) avialans are known from the late Jurassic Tiaojishan Formation of China, dated to about 160 million years ago. Definition Most researchers define Avialae as branch-based clade, though definitions vary. Many authors have used a definition similar to "all theropods closer to birds than to ''Deinonychus''."Weishampel, David B.; Dodson, Peter; Osmólska, Halszka (eds.) (2004). ''The Dinosauria'', Second Edition. University of California Press., 861 pp. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kitadani Formation
The Kitadani Formation ( ja, 北谷層 ''Kitadani-sō'') is a unit of Lower Cretaceous sedimentary rock which crops out near the city of Katsuyama in Fukui Prefecture, Japan, and it is the primary source of Cretaceous-aged non-marine vertebrate fossils in Japan. Dinosaur remains are among the fossils that have been recovered from the formation, but it also preserves a diverse assemblage of plants, invertebrates, and other vertebrates.Weishampel, D.B.; et al. (2004). "Dinosaur distribution (Early Cretaceous, Asia)." In: Weishampel, D.B.; Dodson, P.; and Osmólska, H. (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 563-570. . Most, if not all, of the fossil specimens collected from the Kitadani Formation are reposited at the Fukui Prefectural Dinosaur Museum. The Kitadani Formation is a unit within the Tetori Group, a major sequence of Lower Cretaceous rocks that is distributed across Fukui, Ishikawa, and Gifu prefectures of western-central Honshu. The T ... [...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] |
Coracoid
A coracoid (from Greek κόραξ, ''koraks'', raven) is a paired bone which is part of the shoulder assembly in all vertebrates except therian mammals (marsupials and placentals). In therian mammals (including humans), a coracoid process is present as part of the scapula, but this is not homologous with the coracoid bone of most other vertebrates. In other tetrapods it joins the scapula to the front end of the sternum and has a notch on the dorsal surface which, along with a similar notch on the ventral surface of the scapula, forms the socket in which the proximal end of the humerus (upper arm bone) is located. The acrocoracoid process is an expansion adjacent to this contact surface, to which the shoulderward end of the biceps brachii muscle attaches in these animals. In birds (and generally theropods and related animals), the entire unit is rigid and called scapulocoracoid. This plays a major role in bird flight. In dinosaurs the main bones of the pectoral girdle were the sca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Humerus
The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a rounded head, a narrow neck, and two short processes (tubercles, sometimes called tuberosities). The body is cylindrical in its upper portion, and more prismatic below. The lower extremity consists of 2 epicondyles, 2 processes (trochlea & capitulum), and 3 fossae (radial fossa, coronoid fossa, and olecranon fossa). As well as its true anatomical neck, the constriction below the greater and lesser tubercles of the humerus is referred to as its surgical neck due to its tendency to fracture, thus often becoming the focus of surgeons. Etymology The word "humerus" is derived from la, humerus, umerus meaning upper arm, shoulder, and is linguistically related to Gothic ''ams'' shoulder and Greek ''ōmos''. Structure Upper extremity The upper or pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ulna
The ulna (''pl''. ulnae or ulnas) is a long bone found in the forearm that stretches from the elbow to the smallest finger, and when in anatomical position, is found on the medial side of the forearm. That is, the ulna is on the same side of the forearm as the little finger. It runs parallel to the radius, the other long bone in the forearm. The ulna is usually slightly longer than the radius, but the radius is thicker. Therefore, the radius is considered to be the larger of the two. Structure The ulna is a long bone found in the forearm that stretches from the elbow to the smallest finger, and when in anatomical position, is found on the medial side of the forearm. It is broader close to the elbow, and narrows as it approaches the wrist. Close to the elbow, the ulna has a bony process, the olecranon process, a hook-like structure that fits into the olecranon fossa of the humerus. This prevents hyperextension and forms a hinge joint with the trochlea of the humerus. There is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radius (bone)
The radius or radial bone is one of the two large bones of the forearm, the other being the ulna. It extends from the lateral side of the elbow to the thumb side of the wrist and runs parallel to the ulna. The ulna is usually slightly longer than the radius, but the radius is thicker. Therefore the radius is considered to be the larger of the two. It is a long bone, prism-shaped and slightly curved longitudinally. The radius is part of two joints: the elbow and the wrist. At the elbow, it joins with the capitulum of the humerus, and in a separate region, with the ulna at the radial notch. At the wrist, the radius forms a joint with the ulna bone. The corresponding bone in the lower leg is the fibula. Structure The long narrow medullary cavity is enclosed in a strong wall of compact bone. It is thickest along the interosseous border and thinnest at the extremities, same over the cup-shaped articular surface (fovea) of the head. The trabeculae of the spongy tissue are some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Cretaceous
The Early Cretaceous ( geochronological name) or the Lower Cretaceous (chronostratigraphic name), is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 145 Ma to 100.5 Ma. Geology Proposals for the exact age of the Barremian-Aptian boundary ranged from 126 to 117 Ma until recently (as of 2019), but based on drillholes in Svalbard the defining early Aptian Oceanic Anoxic Event 1a (OAE1a) was carbon isotope dated to 123.1±0.3 Ma, limiting the possible range for the boundary to c. 122–121 Ma. There is a possible link between this anoxic event and a series of Early Cretaceous large igneous provinces (LIP). The Ontong Java-Manihiki-Hikurangi large igneous province, emplaced in the South Pacific at c. 120 Ma, is by far the largest LIP in Earth's history. The Ontong Java Plateau today covers an area of 1,860,000 km2. In the Indian Ocean another LIP began to form at c. 120 Ma, the Kerguelen P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladistic
Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups (" clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived characteristics ( synapomorphies'')'' that are not present in more distant groups and ancestors. However, from an empirical perspective, common ancestors are inferences based on a cladistic hypothesis of relationships of taxa whose character states can be observed. Theoretically, a last common ancestor and all its descendants constitute a (minimal) clade. Importantly, all descendants stay in their overarching ancestral clade. For example, if the terms ''worms'' or ''fishes'' were used within a ''strict'' cladistic framework, these terms would include humans. Many of these terms are normally used paraphyletically, outside of cladistics, e.g. as a 'grade', which are fruitless to precisely delineate, especially when including extinct species. R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Furcula
The (Latin for "little fork") or wishbone is a forked bone found in most birds and some species of non-avian dinosaurs, and is formed by the fusion of the two pink clavicles. In birds, its primary function is in the strengthening of the thoracic skeleton to withstand the rigors of flight. In birds The furcula works as a strut between a bird's shoulders, and articulates to each of the bird's scapulae. In conjunction with the coracoid and the scapula, it forms a unique structure called the triosseal canal, which houses a strong tendon that connects the supracoracoideus muscles to the humerus. This system is responsible for lifting the wings during the recovery stroke. As the thorax is compressed by the flight muscles during downstroke, the upper ends of the furcula spread apart, expanding by as much as 50% of its resting width, and then contracts. X-ray films of starlings in flight have shown that in addition to strengthening the thorax, the furcula acts like a spring in the pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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