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Comstock–Needham System
The Comstock–Needham system is a naming system for insect wing veins, devised by John Comstock and George Needham in 1898. It was an important step in showing the homology of all insect wings. This system was based on Needham's ''pretracheation theory'' that was later discredited by Frederic Charles Fraser in 1938.Fraser, F. C. 1938. A note on the fallaciousness of the theory of pretracheation in the venation of Odonata. ''Proc. Roy. Ent. Soc. London'' (A) 13: 60–70 Vein terminology Longitudinal veins The Comstock and Needham system attributes different names to the veins on an insect's wing. From the anterior (leading) edge of the wing towards the posterior (rear), the major longitudinal veins are named: *''costa'' C, meaning ''rib'' *''subcosta'' Sc, meaning ''below the rib'' *''radius'' R, in analogy with a bone in the forearm, the radius *''media'' M, meaning ''middle'' *''cubitus'' Cu, meaning ''elbow'' *''anal veins'' A, in reference to its posterior location Apart ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wing Vein
Insect wings are adult outgrowths of the insect exoskeleton that enable insects to fly. They are found on the second and third thoracic segments (the mesothorax and metathorax), and the two pairs are often referred to as the forewings and hindwings, respectively, though a few insects lack hindwings, even rudiments. The wings are strengthened by a number of longitudinal veins, which often have cross-connections that form closed "cells" in the membrane (extreme examples include the dragonflies and lacewings). The patterns resulting from the fusion and cross-connection of the wing veins are often diagnostic for different evolutionary lineages and can be used for identification to the family or even genus level in many orders of insects. Physically, some insects move their flight muscles directly, others indirectly. In insects with direct flight, the wing muscles directly attach to the wing base, so that a small downward movement of the wing base lifts the wing itself upward. Those i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Henry Comstock
John Henry Comstock (February 24, 1849 – March 20, 1931) was an eminent researcher in entomology and arachnology and a leading educator. His work provided the basis for classification of butterflies, moths, and scale insects. Early life and education Comstock was born on February 24, 1849 in Janesville, Wisconsin. He studied at Cornell University, graduating in 1874. He also studied at Yale University and the University of Leipzig. In 1878 he married Anna Botsford. She was a wood engraver who beautifully illustrated many of his articles. Comstock became a professor of Nature Studies at Cornell. Career Comstock worked as an instructor at Cornell until 1879. He worked at Vassar College from 1877 to 1879. Between 1879 and 1881 he became the chief Entomologist of the USDA in Washington, D.C. In 1882 he became professor of Entomology and Invertebrate Zoology at Cornell. He also did work in insect morphology and is best known as the co-proposer of the Comstock-Needham system wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James George Needham
James George Needham (March 16, 1868 in Virginia, Illinois – July 24, 1957) was an American entomologist. After studying with John Henry Comstock at Cornell University (1896–1898) he taught biology at Lake Forest University (1898–1907). In 1908 returned to Cornell as assistant professor of limnology. When Comstock retired in 1914, Needham became head of the Department of Entomology at Cornell until his retirement in 1935. Needham published numerous scientific articles, educational papers, and textbooks but is best known for the Comstock–Needham system for describing insect wing venation. He was a Member of the Entomological Society of America, the American Association for the Advancement of Science The American Association for the Advancement of Science (AAAS) is an American international non-profit organization with the stated goals of promoting cooperation among scientists, defending scientific freedom, encouraging scientific respons ... and the Limnological Soc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homology (biology)
In biology, homology is similarity due to shared ancestry between a pair of structures or genes in different taxa. A common example of homologous structures is the forelimbs of vertebrates, where the wings of bats and birds, the arms of primates, the front flippers of whales and the forelegs of four-legged vertebrates like dogs and crocodiles are all derived from the same ancestral tetrapod structure. Evolutionary biology explains homologous structures adapted to different purposes as the result of descent with modification from a common ancestor. The term was first applied to biology in a non-evolutionary context by the anatomist Richard Owen in 1843. Homology was later explained by Charles Darwin's theory of evolution in 1859, but had been observed before this, from Aristotle onwards, and it was explicitly analysed by Pierre Belon in 1555. In developmental biology, organs that developed in the embryo in the same manner and from similar origins, such as from matching p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frederic Charles Fraser
''For others uses see Frederick Fraser (other)'' Frederic Charles Fraser (15 February 1880, in Woolwich – 2 March 1963, in Linwood was an English entomologist who specialised in Odonata. Following army service in India as a surgeon with the rank of lieutenant colonel, Fraser devoted himself entirely to dragonflies, mostly in the British Museum (Natural History), where his collection is maintained. Fraser's correspondence with A. Eric Gardner is in the library of the Natural History Museum, London. Fraser's correspondence with the Irish odonatologist Niall McNeill is in the Oxford University Museum. He was a fellow of the Royal Entomological Society. Selected works * 1933 ''The Fauna of British India, Including Ceylon and Burma'' including Burma and CeyloOdonata. 1 Introduction, Coenagriidae. New Delhi.423pp. * 1934 ''The Fauna of British India, Including Ceylon and Burma'' including Burma and CeyloOdonata. 2 Agriidae, Gomphidae. New Delhi.398 pp, 120 figures, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anterior
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabularies for subdisciplines of anatomy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior (anatomy)
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axis, anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anatomical Terms Of Location
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabularies for subdisciplines of anatom ... [...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] |
Humeral
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 pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomson Brooks/Cole
The Thomson Corporation was one of the world's largest information companies. It was established in 1989 following a merger between International Thomson Organisation Ltd (ITOL) and Thomson Newspapers. In 2008, it purchased Reuters Group to form Thomson Reuters. The Thomson Corporation was active in financial services, healthcare sectors, law, science and technology research and tax and accounting sectors. The company operated through five segments (2007 onwards): Thomson Financial, Thomson Healthcare, Thomson Legal, Thomson Scientific and Thomson Tax & Accounting. Until 2007, Thomson was also a major worldwide provider of higher education textbooks, academic information solutions and reference materials. On 26 October 2006, Thomson announced the proposed sale of its Thomson Learning assets. In May 2007, Thomson Learning was acquired by Apax Partners and subsequently renamed Cengage Learning in July. The Thomson Learning brand was used to the end of August 2007. Subsequently, on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
