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Parabohaiornis
''Parabohaiornis'' is an extinct genus of bohaiornithid enantiornithean dinosaur known from the Early Cretaceous of Liaoning Province, northeastern China. It contains a single species, ''Parabohaiornis martini''. Discovery ''Parabohaiornis'' was first described and named by Min Wang, Zhong-He Zhou, Jingmai K. O'Connor and Nikita V. Zelenkov in 2014 and the type species is ''Parabohaiornis martini''. The generic name combines the Latin prefix ''para'', meaning "close to", with the generic name of '' Bohaiornis'', the type genus of the Bohaiornithidae family, in reference to the morphological similarity between ''Parabohaiornis'' and other bohaiornithids. The specific name, ''martini'', honors the late paleontologist Prof. Larry Dean Martin, for his contributions to the study of the evolution of birds. ''Parabohaiornis'' is known from the holotype IVPP V 18691, a nearly complete and partially articulated skeleton and skull, and from the referred specimen IVPP V 18690, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enantiornithes
The Enantiornithes, also known as enantiornithines or enantiornitheans in literature, are a group of extinct avialans ("birds" in the broad sense), the most abundant and diverse group known from the Mesozoic era. Almost all retained teeth and clawed fingers on each wing, but otherwise looked much like modern birds externally. Over eighty species of Enantiornithes have been named, but some names represent only single bones, so it is likely that not all are valid. The Enantiornithes became extinct at the Cretaceous–Paleogene boundary, along with Hesperornithes and all other non-avian dinosaurs. Discovery and naming The first Enantiornithes to be discovered were incorrectly referred to modern bird groups. For example, the first known species of Enantiornithes, ''Gobipteryx minuta'', was originally considered a paleognath related to ostriches and tinamou. The Enantiornithes were first recognized as a distinct lineage, or "subclass" of birds, by Cyril A. Walker in 1981. Walker mad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bohaiornithidae
Bohaiornithidae is a group of early predatory enantiornitheans from the early Cretaceous Period of China. All known specimens come from the Jiufotang Formation and Yixian Formation, dating to the early Aptian age, 125–120 million years ago. Bohaiornithidae was first coined as a family of enantiornithean birds by Wang and colleagues in 2014. They defined it as the natural group formed by all descendants of the common ancestor of the type species, '' Bohaiornis guoi'', and '' Shenqiornis mengi''.Wang M., Zhou Z.-H., O’Connor, J.K., and Zelenkov, N.V. (2014A new diverse enantiornithine family (Bohaiornithidae fam. nov.) from the Lower Cretaceous of China with information from two new species ''Vertebrata PalAsiatica'', 52(1): 31-76. Description Similar to most enantiornitheans, bohaiornithids possessed teeth rather than a beak as in modern birds, although they could be distinguished from other enantiornitheans due to the structure of their teeth. Their teeth were large, robust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bohaiornithid
Bohaiornithidae is a group of early predatory enantiornitheans from the early Cretaceous Period of China. All known specimens come from the Jiufotang Formation and Yixian Formation, dating to the early Aptian age, 125–120 million years ago. Bohaiornithidae was first coined as a family of enantiornithean birds by Wang and colleagues in 2014. They defined it as the natural group formed by all descendants of the common ancestor of the type species, ''Bohaiornis guoi'', and '' Shenqiornis mengi''.Wang M., Zhou Z.-H., O’Connor, J.K., and Zelenkov, N.V. (2014A new diverse enantiornithine family (Bohaiornithidae fam. nov.) from the Lower Cretaceous of China with information from two new species ''Vertebrata PalAsiatica'', 52(1): 31-76. Description Similar to most enantiornitheans, bohaiornithids possessed teeth rather than a beak as in modern birds, although they could be distinguished from other enantiornitheans due to the structure of their teeth. Their teeth were large, robust and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enantiornithean
The Enantiornithes, also known as enantiornithines or enantiornitheans in literature, are a group of extinct avialans ("birds" in the broad sense), the most abundant and diverse group known from the Mesozoic era. Almost all retained teeth and clawed fingers on each wing, but otherwise looked much like modern birds externally. Over eighty species of Enantiornithes have been named, but some names represent only single bones, so it is likely that not all are valid. The Enantiornithes became extinct at the Cretaceous–Paleogene boundary, along with Hesperornithes and all other non-avian dinosaurs. Discovery and naming The first Enantiornithes to be discovered were incorrectly referred to modern bird groups. For example, the first known species of Enantiornithes, '' Gobipteryx minuta'', was originally considered a paleognath related to ostriches and tinamou. The Enantiornithes were first recognized as a distinct lineage, or "subclass" of birds, by Cyril A. Walker in 1981. Walker mad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Institute Of Vertebrate Paleontology And Paleoanthropology
The Institute of Vertebrate Paleontology and Paleoanthropology (IVPP; ) of China is a research institution and collections repository for fossils, including many dinosaur and pterosaur specimens (many from the Yixian Formation). As its name suggests, research is focused on both paleontological topics and those relating to human prehistory. The institution, located in Beijing, grew out of the Cenozoic Research Laboratory in 1929 and is its own institution under the Chinese Academy of Sciences. Its staff have increasingly worked internationally, participating in the China-Canada Dinosaur Project from 1986 to 1991 and authoring or coauthoring forty-five ''Nature'' and ''Science'' articles from 1999 to 2005. Notable paleontologists who have been affiliated with the IVPP include Yang Zhongjian (also known as C. C. Young), Dong Zhiming, Meemann Chang and Zhao Xijin Zhao Xijin (赵喜进; born c. 1935 died July 21, 2012) was a Chinese paleontologist notable for having named numerous di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skeleton
A skeleton is the structural frame that supports the body of an animal. There are several types of skeletons, including the exoskeleton, which is the stable outer shell of an organism, the endoskeleton, which forms the support structure inside the body, and the hydroskeleton, a flexible internal skeleton supported by fluid pressure. Vertebrates are animals with a vertebral column, and their skeletons are typically composed of bone and cartilage. Invertebrates are animals that lack a vertebral column. The skeletons of invertebrates vary, including hard exoskeleton shells, plated endoskeletons, or Sponge spicule, spicules. Cartilage is a rigid connective tissue that is found in the skeletal systems of vertebrates and invertebrates. Etymology The term ''skeleton'' comes . ''Sceleton'' is an archaic form of the word. Classification Skeletons can be defined by several attributes. Solid skeletons consist of hard substances, such as bone, cartilage, or cuticle. These can be further ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skull
The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, these two parts are the neurocranium and the viscerocranium ( facial skeleton) that includes the mandible as its largest bone. The skull forms the anterior-most portion of the skeleton and is a product of cephalisation—housing the brain, and several sensory structures such as the eyes, ears, nose, and mouth. In humans these sensory structures are part of the facial skeleton. Functions of the skull include protection of the brain, fixing the distance between the eyes to allow stereoscopic vision, and fixing the position of the ears to enable sound localisation of the direction and distance of sounds. In some animals, such as horned ungulates (mammals with hooves), the skull also has a defensive function by providing the mount (on the front ... [...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] |
Beijing
} Beijing ( ; ; ), alternatively romanized as Peking ( ), is the capital of the People's Republic of China. It is the center of power and development of the country. Beijing is the world's most populous national capital city, with over 21 million residents. It has an administrative area of , the third in the country after Guangzhou and Shanghai. It is located in Northern China, and is governed as a municipality under the direct administration of the State Council with 16 urban, suburban, and rural districts.Figures based on 2006 statistics published in 2007 National Statistical Yearbook of China and available online at archive. Retrieved 21 April 2009. Beijing is mostly surrounded by Hebei Province with the exception of neighboring Tianjin to the southeast; together, the three divisions form the Jingjinji megalopolis and the national capital region of China. Beijing is a global city and one of the world's leading centres for culture, diplomacy, politics, finance, busi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolution Of Birds
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation tends to exist within any given population as a result of genetic mutation and recombination. Evolution occurs when evolutionary processes such as natural selection (including sexual selection) and genetic drift act on this variation, resulting in certain characteristics becoming more common or more rare within a population. The evolutionary pressures that determine whether a characteristic is common or rare within a population constantly change, resulting in a change in heritable characteristics arising over successive generations. It is this process of evolution that has given rise to biodiversity at every level of biological organisation, including the levels of species, individual organisms, and molecules. The theory of evolution by na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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