The Experts below are selected from a list of 8748 Experts worldwide ranked by ideXlab platform
Rolf G. Beutel - One of the best experts on this subject based on the ideXlab platform.
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A review of methods for analysing Insect structures - the role of Morphology in the age of phylogenomics.
Current opinion in insect science, 2016Co-Authors: Benjamin Wipfler, Hans Pohl, Margarita Yavorskaya, Rolf G. BeutelAbstract:Techniques currently used in Insect Morphology are outlined briefly. Scanning electron microscopy (SEM) and microphotography are used mainly for documenting external features, the former providing more information on tiny surface structures and the latter on coloration, transparency and degree of sclerotization. A broad spectrum of methods is now available for anatomical studies: histological serial sections, confocal laser scanning microscopy (CLSM), light-sheet fluorescence microscopy (LSFM), serial block-face scanning electron microscopy (SBFSEM), dual beam scanning electron microscopy (FIB-SEM), nuclear magnetic resonance imaging (NMRI), and μ-computed tomography (micro-CT). The use of SBFSEM and FIB-SEM is restricted to extremely small samples. NMRI is used mainly in in vivo studies. Micro-computed tomography, in combination with computer-based reconstruction, has greatly accelerated the acquisition of high quality data in a phylogenetic context. Morphology will continue to play a vital role in phylogenetic and evolutionary investigations. It provides independent data for checking the plausibility of molecular phylogenies and is the only source of information for placing extinct taxa. It is the necessary basis for reconstructing character evolution on the phenotypic level and for developing complex evolutionary scenarios. Computer-based anatomical ontologies are an additional future perspective of morphological work.
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Insect Morphology and Phylogeny: A Textbook For Students Of Entomology
2013Co-Authors: Rolf G. Beutel, Frank Friedrich, Xing-ke YangAbstract:This textbook provides an in-depth treatment of the structures and the phylogeny of the megadiverse Hexapoda. It presents an up-to-date overview of general Insect Morphology with detailed drawings, scanning electron micrographs, and 3-D reconstructions and is a modern synthesis of Insect systematics. The work is an invaluable reference for students and researchers of biology and is a must for evolutionary biologists.
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Insect Morphology in the age of phylogenomics: innovative techniques and its future role in systematics
Entomological Science, 2013Co-Authors: Frank Friedrich, Yoko Matsumura, Hans Pohl, Ming Bai, Thomas Hörnschemeyer, Rolf G. BeutelAbstract:A brief account of the history of Insect Morphology is given. Different techniques and analytical methods used in current projects on Insect Morphology and phylogeny and their optimized combined application are described. These include fixation, dissection, maceration, histology (microtome sectioning), scanning electron microscopy (SEM), transmission electron microscopy (TEM), serial block-face scanning electron microscopy (SBFSEM), focused ion beam scanning electron microscopy (FIB/SEM), confocal laser scanning microscopy (CLSM), bleaching, micro-computed tomography (μCT), computer-based three-dimensional reconstruction, focus stacking of digital images, geometric morphometrics and the storage of morphological metadata. The role of Insect Morphology in the “age of phylogenomics” is discussed.
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Micro-computer tomography and a renaissance of Insect Morphology
Developments in X-Ray Tomography VI, 2008Co-Authors: Frank Friedrich, Rolf G. BeutelAbstract:ABSTRACT The use of new technologies, especially computer-based three dimensional reconstructions and micro-computer tomo-graphy (µ-CT) have greatly improved and facilitated the detailed investigation of Insect anatomy. Optimal results in morphological work aiming at phylogenetic reconstruction can be obtained with a combined application of different techniques such as histology, scanning electron microscopy, and µ-CT. The use of µ-CT greatly enhances the efficiency of the acquisition of detailed anatomical data and allows a br oad taxon sampling in phylogenetic studies partly or entirely based on morphological characters. A disadvantage of phase contrasted µ-CT images is the poor differentiation of differ-ent tissue types. This problem can be overcome by the use of stable low energy photon beams as available at the beam-line BW2 of the Deutsches Elektronen-Synchrotron in Hamburg (DESY). Synchrotron-radiation-based µ-Ct data (SR µ-CT) obtained with this approach are an ideal basis for highl y efficient three dimensional reconstructions of high quality.
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The Phylogeny of Archostemata (Coleoptera) and new Approaches in Insect Morphology Zur Phylogenie der Archostemata (Coleoptera) und neue Ansätze zur Insektenmorphologie
Entomologia Generalis, 2008Co-Authors: Rolf G. Beutel, Frank FriedrichAbstract:This study gives an overview of recent developments and results in the morphological and phylogenetic study of Archostemata, and a short account of innovative morphological techniques such as for instance micro computer tomography (μ-CT) and computer based 3-dimensional reconstructions. Archostemata are a small relict group of beetles. They display a mosaic pattern of highly derived characters, mainly of the head, and of plesiomorphic features, mainly of the thorax. The results of recent cladistic analyses suggest that Ommatidae, Cupedidae, Micromalthidae, Crowsoniellidae and Jurodidae (Sikhotealinia and †Jurodes), and the extinct families †Schizophoridae, †Catiniidae, and tAdemosynidae form a clade Archostemata. However, the placement of Jurodidae and the three fossil groups remains ambiguous, mainly due to lack of reliable morphological data. Within Archostemata, Ommatidae are probably the most basal group and recent cladistic analyses suggest that Jurodidae may form the sistergroup of a clade comprising Micromalthidae, Crowsoniellidae, †Schizophoridae, tCatiniidae, and †Ademosynidae. Archostemata is the sistergroup of the remaining three beetle suborders. All Permian fossil lineages traditionally assigned to Archostemata belong to the stem group of Coleoptera, with a branching pattern (†Tshekardocoleidae + (†Permocupedidae + (†Rhombocoleidae + (tTriadocupedinae + (Coleoptera s.str. [=crown group]))))). The reconstruction of the phylogeny of Archostemata is still impeded by a severe lack of material and morphological data. Intensive collecting activities should have high priority, combined with the application of traditional and modem morphological methods. Innovative techniques have given new and strong impulses to Insect Morphology in the last years.
Valerie Schawaroch - One of the best experts on this subject based on the ideXlab platform.
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Three-dimensional visualization of Insect Morphology using confocal laser scanning microscopy
Journal of Microscopy, 2003Co-Authors: A. V. Klaus, Varuni L Kulasekera, Valerie SchawarochAbstract:Cuticular structures of Insects are often microscopic and intricately complex; among the most complex structures are male genitalia. Genitalic structures are essential in taxonomic and phylogenetic studies of Insects. Using well-described species from two disparate dipteran genera, we demonstrate the utility of confocal laser scanning microscopy for studying the morphological characters of fly genitalia by taking advantage of the autofluorescent properties of cuticle material. Reconstructions of confocal data sets obtained from genitalic structures embedded in two commonly used entomological mounting media (euparal and glycerin jelly) are presented. Aberration artefacts often observed in confocal data obtained from thick specimens were analysed and strategies for their minimization are discussed. Our results indicate that confocal laser scanning microscopy and 3D reconstruction are excellent techniques for visualizing small, complex, autofluorescent structures in flies. These techniques could have a profound impact on the quality of information provided by 3D representations of Insect structures over more traditional methods of visualization.
Hong-zhang Zhou - One of the best experts on this subject based on the ideXlab platform.
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Penetrating view of nano-structures in Aleochara verna spermatheca and flagellum by hard X-ray microscopy
Chinese Physics B, 2013Co-Authors: Kun Zhang, Youli Hong, Peiping Zhu, Qx Yuan, Wx Huang, K. Gao, Hong-zhang ZhouAbstract:A penetrating view of the three-dimensional nanostructure of female spermatheca and male flagellum in the species Aleochara verna is obtained with 100-nm resolution using a hard X-ray microscope, which provides a fast noninvasive imaging technology for Insect Morphology. Through introducing Zernike phase contrast and heavy metal staining, images taken at 8 keV displayed sufficient contrast for observing nanoscale fine structures, such as the spermatheca cochleate duct and the subapex of the flagellum, which have some implications for the study of the sperm transfer process and genital evolution in Insects. This work shows that both the spatial resolution and the contrast characteristic of hard X-ray microscopy are quite promising for Insect Morphology studies and, particularly, provide an attractive alternative to the destructive techniques used for investigating internal soft tissues.
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3D visualization of the microstructure of Quedius beesoni Cameron using micro-CT
Analytical and bioanalytical chemistry, 2010Co-Authors: Kai Zhang, Youli Hong, Peiping Zhu, Qingxi Yuan, Wanxia Huang, Xiaosong Liu, Gun Gao, Hong-zhang ZhouAbstract:The investigation of the internal Morphology of Insects is usually performed using classical microtomy yielding optical micrographs of stained thin sections. The achievement of high-quality cross sections for microtomy is time-consuming and the risk of damaging sections is unavoidable. Moreover, the approach is impractical, in particular when quick acquisition of 3D structural information is required. Recently, X-ray computed microtomography (micro-CT) with a high spatial resolution was considered as a potential tool for the morphological classification of Insects. We used micro-CT to investigate Quedius beesoni Cameron at the cellular length scale. This method provides a new powerful and nondestructive approach to obtain 3D structural information on the biological organization of Insects. The preliminary images presented in this contribution clearly reveal the endoskeleton and the muscles of the head and the thorax with a full 3D structure. We also reconstructed the 3D structure of the brain of Quedius beesoni Cameron, and this is the first reconstruction in Staphylinidae, which will be a great advancement for morphological and phylogenic research. We claim that both the spatial resolution and the contrast characteristic of micro-CT imaging may fulfill the requirements necessary for zoological Insect Morphology and phylogeny, in particular, when a classification of a rare and unique Insect specimen is required.
Claudio R. Lazzari - One of the best experts on this subject based on the ideXlab platform.
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In memoriam of Prof. Josué A. Núñez (1924–2014).
Journal of insect physiology, 2015Co-Authors: Claudio R. Lazzari, Martin Giurfa, Walter M. Farina, Flavio RocesAbstract:International audienceProf. Josué Núñez passed away on August 19th 2014 at the age of 89. He was a pioneer in the field of Insect physiology and a founder of the study of behavioural physiology in Argentina and other Latin-American countries such as Brazil and Venezuela. Josué was born in 1924, in the city of Tapalqué, a small town in the middle of the province of Buenos Aires, Argentina. After a basic education in the prestigious ''Colegio Nacional de Buenos Aires'', he studied biology at the University of Buenos Aires, where he obtained his PhD in 1953. Throughout his long and fructiferous scientific career, he worked in different reputed laboratories around the world. Thanks to grants from the Alexander-von-Humboldt foundation, he stayed several years in Germany, 1983, after the end of Argentina's worst military dictatorship, he returned to his country, where he was appointed as a Full Professor of the University of Buenos Aires and as a Principal Investigator of the Argentinean National Research Council. During this period of national reconstruction, he played a most significant role for the development of biological studies and the training of young students. He participated actively in the creation of a new curriculum in biological sciences, incorporating several areas of study and research such as Animal Physiology, Behavioral Physiology and Insect Physiology, which were relegated until then. In addition, he founded, together with Hector Maldonado, the first laboratory of Behavioural Physiology, and later the laboratory of Insect Physiology, contributing thereby to the training of several generations of students, many of whom occupy currently chairs and professorships in Argentina and Europe. Josué Núñez retired officially in 1990 but continued his scientific activities in an intensive way thanks to a nomination as a Consultant Professor of the University of Buenos Aires, a position he kept until 2008. In 2007, he was elected as a member of the Buenos Aires Academy of Sciences. Josué Núñez was passionate about Insects and made several seminal contributions on Insect Morphology, physiology and behaviour. His work was extremely inventive and was characterized by the development and successful employ of self-made ingenious tools and experimental devices, such as regulated artificial feeders for honeybees and haematophagous bugs, aimed at quantifying responses in unrestrained, free-behaving Insects under controlled conditions. His main study models were precisely blood-sucking bugs and honeybees, and his original contributions underlie the strong ''feeling for the organism'' he had when posing relevant scientific questions. Among his numerous contributions, one can cite the discovery of prothoracic glands and the first experimental evidence of neuro-hormonal control of diuresis in Coleop-tera, the nervous control of both the mechanical properties of the cuticle and the diuretic activity in Rhodnius blood-sucking bugs, the neural regulation of ingestion in dipterans, the use of repellent pheromones during foraging in honeybees, the control of crop-filling in honeybees that led to the hypothesis of a trade-off between individual and colony-wide foraging efficiency, mediated by communication , in social Insects, and the perception of infrared radiation in haematophagous bugs, among others. Josué Núñez received several prestigious distinctions from the Argentinean scientific community such as the Konex Prize for science and technology, awarded twice to him, in 1993 and 2003. He himself, however, never regarded these many awards as very important; humility and a devoted commitment to science characterized his style, which was always accompanied by a high dose of sense of humour, something that everyone who had the privilege of working under his direction remembers fondly. Josué exerted a strong influence on his numerous students, to whom he transmitted his passion, curiosity and scientific rigour. He recognized that students and young scientists need to learn to be independent, so he gave them independence. His collaborators will never forget the endless discussions about their ongoing projects, his unorthodox manner, nor the long and intellectually enriching, open-end talks on subjects as eclectic as the beginnings of Insect physiology, fractals, complex systems, bio-mimetics, bio-food and eco-engineering, always accompanied by litres of mate, an Argentinean typical infusion. Our sadness over Josué's death is somehow alleviated by the fact that his scientific legacy will enrich us for many generations to come and by the happy memories of the rich years that we were allowed to spend with him
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In memoriam of Prof. Josué A. Núñez (1924–2014)
Journal of Insect Physiology, 2014Co-Authors: Claudio R. Lazzari, Walter Marcelo Farina, Martin Giurfa, Roces RocesAbstract:Prof. Josué Núñez passed away on August 19th 2014 at the age of 89. He was a pioneer in the field of Insect physiology and a founder of the study of behavioural physiology in Argentina and other Latin-American countries such as Brazil and Venezuela. Josué was born in 1924, in the city of Tapalqué, a small town in the middle of the province of Buenos Aires, Argentina. After a basic education in the prestigious ''Colegio Nacional de Buenos Aires'', he studied biology at the University of Buenos Aires, where he obtained his PhD in 1953. Throughout his long and fructiferous scientific career, he worked in different reputed laboratories around the world. Thanks to grants from the Alexander-von-Humboldt foundation, he stayed several years in Germany, 1983, after the end of Argentina's worst military dictatorship, he returned to his country, where he was appointed as a Full Professor of the University of Buenos Aires and as a Principal Investigator of the Argentinean National Research Council. During this period of national reconstruction, he played a most significant role for the development of biological studies and the training of young students. He participated actively in the creation of a new curriculum in biological sciences, incorporating several areas of study and research such as Animal Physiology, Behavioral Physiology and Insect Physiology, which were relegated until then. In addition, he founded, together with Hector Maldonado, the first laboratory of Behavioural Physiology, and later the laboratory of Insect Physiology, contributing thereby to the training of several generations of students, many of whom occupy currently chairs and professorships in Argentina and Europe. Josué Núñez retired officially in 1990 but continued his scientific activities in an intensive way thanks to a nomination as a Consultant Professor of the University of Buenos Aires, a position he kept until 2008. In 2007, he was elected as a member of the Buenos Aires Academy of Sciences. Josué Núñez was passionate about Insects and made several seminal contributions on Insect Morphology, physiology and behaviour. His work was extremely inventive and was characterized by the development and successful employ of self-made ingenious tools and experimental devices, such as regulated artificial feeders for honeybees and haematophagous bugs, aimed at quantifying responses in unrestrained, free-behaving Insects under controlled conditions. His main study models were precisely blood-sucking bugs and honeybees, and his original contributions underlie the strong ''feeling for the organism'' he had when posing relevant scientific questions. Among his numerous contributions, one can cite the discovery of prothoracic glands and the first experimental evidence of neuro-hormonal control of diuresis in Coleop-tera, the nervous control of both the mechanical properties of the cuticle and the diuretic activity in Rhodnius blood-sucking bugs, the neural regulation of ingestion in dipterans, the use of repellent pheromones during foraging in honeybees, the control of crop-filling in honeybees that led to the hypothesis of a trade-off between individual and colony-wide foraging efficiency, mediated by communication , in social Insects, and the perception of infrared radiation in haematophagous bugs, among others. Josué Núñez received several prestigious distinctions from the Argentinean scientific community such as the Konex Prize for science and technology, awarded twice to him, in 1993 and 2003. He himself, however, never regarded these many awards as very important; humility and a devoted commitment to science characterized his style, which was always accompanied by a high dose of sense of humour, something that everyone who had the privilege of working under his direction remembers fondly. Josué exerted a strong influence on his numerous students, to whom he transmitted his passion, curiosity and scientific rigour. He recognized that students and young scientists need to learn to be independent, so he gave them independence. His collaborators will never forget the endless discussions about their ongoing projects, his unorthodox manner, nor the long and intellectually enriching, open-end talks on subjects as eclectic as the beginnings of Insect physiology, fractals, complex systems, bio-mimetics, bio-food and eco-engineering, always accompanied by litres of mate, an Argentinean typical infusion. Our sadness over Josué's death is somehow alleviated by the fact that his scientific legacy will enrich us for many generations to come and by the happy memories of the rich years that we were allowed to spend with him.
A. V. Klaus - One of the best experts on this subject based on the ideXlab platform.
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Three-dimensional visualization of Insect Morphology using confocal laser scanning microscopy
Journal of Microscopy, 2003Co-Authors: A. V. Klaus, Varuni L Kulasekera, Valerie SchawarochAbstract:Cuticular structures of Insects are often microscopic and intricately complex; among the most complex structures are male genitalia. Genitalic structures are essential in taxonomic and phylogenetic studies of Insects. Using well-described species from two disparate dipteran genera, we demonstrate the utility of confocal laser scanning microscopy for studying the morphological characters of fly genitalia by taking advantage of the autofluorescent properties of cuticle material. Reconstructions of confocal data sets obtained from genitalic structures embedded in two commonly used entomological mounting media (euparal and glycerin jelly) are presented. Aberration artefacts often observed in confocal data obtained from thick specimens were analysed and strategies for their minimization are discussed. Our results indicate that confocal laser scanning microscopy and 3D reconstruction are excellent techniques for visualizing small, complex, autofluorescent structures in flies. These techniques could have a profound impact on the quality of information provided by 3D representations of Insect structures over more traditional methods of visualization.