Dissertations / Theses: 'Functional morphology and anatomy'

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Anderson, Jason S. 1969. "Anatomy, functional morphology and phylogeny of Aistopoda (Tetrapoda, Lepospondyli)." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36869.

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The importance of fossils to phylogenetic reconstruction is well established. However, analyses of fossil data sets are confounded by problems related to the incomplete nature of the specimens. Taxa that are incompletely known are problematic because of the uncertainty of their placement within a tree, leading to a proliferation of most parsimonious solutions because of wild card behavior. Problematic taxa are commonly deleted based on a priori criteria of completeness. Paradoxically, a taxon's problematic behavior is tree dependent, and levels of completeness are not necessarily associated with problematic behavior. Exclusion of taxa based on completeness eliminates real character conflict and, by not allowing incomplete taxa to determine tree topology, the phylogenetic hypothesis is diminished.
A method is proposed to allow optimization of taxonomic inclusion and tree stability. It identifies and removes taxa causing multiple most parsimonious solutions, producing a more stable topology, called the phylogenetic trunk. This method is used in an analysis of the Paleozoic Lepospondyli. A single most parsimonious tree, or trunk, was found after removal of one taxon identified as being problematic. The 38 trees found one additional step from this primary trunk are reduced to two by removal of one additional taxon. These trunks are compared to the trees found by excluding taxa with various degrees of completeness. Effects of incomplete taxa are explored by comparison with the stable tree. Correlated characters associated with limblessness are discussed regarding the assumption of character independence. Inclusion of intermediate taxa is found to be the single best method for breaking down long branches.

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Whitehead, Paul Frederick. "Functional Anatomy of the Forelimb in Terrestrial and Arboreal African Cercopithecoids." Thesis, Yale University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10957344.

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The cercopithecoid monkeys, though sharing a common body-plan, exhibit considerable behavioral, ecological, and anatomical diversity. The theme of this work is the relationship between anatomy, postural behavior, and habitat use, concentrating upon the distal forearm, wrist and hand. It incorporates an initial review of the relevant empirical and theoretical literature, and original research including anatomy, naturalistic and experimental observation, and a first detailed description of fossil forelimb material of the "giant" extinct baboon, Theropithecus oswaldi. Two modes of contact between hand and substrate in monkeys are distinguished. Palmigrady is characteristic of predominately arboreal species, while species that habitually walk on the ground do so using a distinctive digitigrade gait. The vervet monkey (Cercopithecus [now Chiorocebus] aethiops, s.l.) occupies many tropical, seasonal habitats, and, uniquely, is both polymorphic and polytypic with respect to hand posture. The author's fieldwork found that as expected, digitigrady is apparently favored by vervets living in drier, more open habitats. The mid section of the dissertation reviews in depth the copious and often confusing literature on primate, especially cercopithecoid, taxonomy, and the many contradictory schemes that have attempted to categorize primate positional behavior.

Variation in the intermetacarpal and other wrist joints in human subjects provides background for recognition of character states distinguishing obligate digitigrade (patas and baboon) from palmigrade (colobus) monkey genera. It is then demonstrated that, consistent with the observation of hand posture variation in living subjects, anatomical variation among individual vervet skeletons encompasses both types. Unexpectedly, the large fossil T. oswaldi (but not T. geiada) shows palmigrade features in some aspects of carpal structure. This theme is pursued in the most extensive section of the dissertation, which includes a detailed description and interpretation of fossil forelimb specimens assigned to Theropithecus oswaldi, from the sites of Olorgesailie (Kenya) and Olduvai Gorge (Tanzania) . The descriptions include notes comparing the fossils with extant cercopithecoids, and interpreting similarities and differences. These comparisons suggest that T. oswaldi did not closely resemble extant baboons in locomotor behavior, and may have been palmigrade on the ground. Finally, the concluding sections describe an innovative set of techniques that were used successfully to collect electromyographic and cineradiographic data on monkeys locomoting in a controlled laboratory setting, with a view to confirming the functional interpretation of anatomical features of living and fossil forms, and the naturalistic behavior of living vervets.

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Habegger, María Laura. "Functional Morphology and Feeding Mechanics of Billfishes." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5617.

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Billfishes (marlins, spearfishes, sailfishes and swordfish) are one of the fastest and largest marine apex predators, and perhaps their most recognizable attribute is their bill or rostrum. The proposed function for this novel structure has ranged from hydrodynamic enhancement to defensive weaponry. However, the most supported hypothesis for its function has been linked to feeding. Billfishes have been observed to subdue their prey with their rostrum, either stunning or cutting them into pieces before ingestion. Due to their large body sizes and pelagic lifestyles a thorough investigation of the function of this structure has been logistically challenging. The goal of my dissertation is to investigate the role of the rostrum during feeding from a functional, mechanical and morphological standpoint. By the use of interdisciplinary approaches that blend engineering with biology, the function of the rostrum and billfish putative feeding behavior was investigated. By the use of different approaches that involve morphological characterizations, histology, estimation of performance measurements such as bite force and the investigation architectural tradeoffs from geometric morphometrics analysis, my dissertation aims to characterized the role of the rostrum in billfishes as a possible adaptation for feeding. Results showed that the rostrum in billfishes is mechanically capable of acting as a feeding weapon; continuous stress distribution along its length suggest no particular point that could lead to breakage during feeding. Finite element analysis, as well as bending experiments suggest feeding behavior may be species specific and strictly associated with rostrum morphology. While istiophorids may be morphologically suited to strike their prey with a wide range of motions, swordfish appear to be specialized from a mechanical and hydrodynamic standpoint to hit their prey with lateral strikes. Biting performance is relatively low in these top predators compared to other non-billfish species suggesting the rostrum may facilitate prey processing reducing the need for powerful biting. However contrary to my expectations rostrum length was not a predictor of bite force. Skull variation was evident among billfish species. Swordfish, the species with the longest rostrum, had the smallest head and the lowest relative bite force whereas blue marlin, the species with the stiffer, most compact rostrum, had the largest head and one of the greatest relative bite forces. The shortbill spearfish showed a relatively low bite force indicating predatory success in this species may be linked to an extended lower jaw that may facilitate a speed efficient jaw during prey capture. Whether the rostrum in billfishes has evolved as an adaptation for feeding, remains uncertain. However results from this study demonstrate that rostrum material properties, morphology and head architecture, in addition to relatively low biting performance in billfishes, favor a role of prey capture for the rostrum.

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Sangster, Sarah. "The anatomy, functional morphology and systematics of Dimorphodon macronyx (Diapsida: Pterosauria)." Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.620016.

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Mulvany, Samantha Lynn. "Evolution and Functional Morphology of the Cephalic Lobes in Batoids." Scholar Commons, 2013. https://scholarcommons.usf.edu/etd/5083.

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Cephalic lobes are unique structures derived from the anterior pectoral fins, found in select myliobatid stingrays. Many benthic batoids utilize undulatory locomotion and use their pectoral fins for both locomotion and prey capture. Pelagic myliobatids that possess cephalic lobes utilize oscillatory locomotion, using their pectoral fins to locomote and their cephalic lobes for prey capture. Despite differences in habitat usage and locomotor modes, these batoids feed on very similar benthic organisms. The purpose of this study was to 1.) compare the morphology of the cephalic lobes and anterior pectoral fins in lobed and lobeless species, looking at skeletal elements, musculature and electrosensory pore distributions; 2.) compare prey capture kinematics in lobed and lobeless species and examine the role of the cephalic lobes in prey capture modulation due to elusive/non-elusive prey; 3.) analyze multiple morphological and behavioral variables to establish any correlations to the presence of cephalic lobes. Radiography, dissections and staining techniques were employed to examine the morphology of the cephalic lobes and anterior pectoral fins in six species of batoids. High speed videography was used to film prey capture behavior in five batoid species, using elusive and non-elusive prey. Continuous morphological and behavioral variables were used to determine any correlations with the presence of the cephalic lobes, taking phylogeny into account. Results indicate that the skeletal components of the pectoral fins of oscillatory species are very different from pectoral fins of undulatory species as well as the cephalic lobes. Second moment of area (I), showed that the cephalic lobes and pectoral fins in undulatory species had greater resistance to bending in multiple directions and were also more flexible. The cephalic lobes had a novel muscle layer compared to the pectoral fin musculature. Electorsensory pores were absent from the anterior pectoral fins in oscillatory batoids, but numerous on the cephalic lobes and anterior pectoral fins in undulatory batoids. The distribution of the electrosensory pores was uniform with the exception of Rhinoptera bonasus, which possessed higher pore numbers along the edges of the cephalic lobes. Overall, the morphology of the cephalic lobes is distinct, but more similar to the pectoral fins of undulators compared to oscillators. Kinematic data showed that species with cephalic lobes localize prey capture to the cephalic region of the body. Lobed species were faster at pouncing and tenting prey, but slower during biting. The cephalic lobes were able to move more in the vertical and horizontal plane compared to the anterior pectoral fins. All species were able to modulate prey capture behavior to some degree. Species lacking lobes spent more time handling elusive prey compared to non-elusive prey. For all species, elusive prey were farther from the mouth during biting but prey escapes were rare. Lobed species were overall faster in prey capture, but did not display more modulation or feeding success than lobeless species. Phylogenetically corrected correlations showed that most morphological variables correlated to the appearance of the cephalic lobes, while kinematics variables did not. There was also a correlation among habitat, locomotion and the cephalic lobes. The cephalic lobes may have played a key role in partitioning prey capture to the head region, maintaining dexterity in the lobes while allowing the pectoral fins to shift to oscillatory locomotion and consequently a pelagic lifestyle.

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Schwager, Hannes. "Functional Anatomy and Development of Cactus Ramifications." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-175892.

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Cacti (Cactaceae) represent a family of highly specialized angiosperm plants with a native range of distribution restricted to the American continents. Columnar cacti of the sub-family Cactoideae evolved in adaptation to their arid or semi-arid habitats characteristics that distinguish them from most other dicot plants, e.g. the stem succulence with a strongly vascularized storage parenchyma and the presence of the spine wearing areoles. Although cacti have been in cultivation since the discovery of America, some studies even suggest the agricultural use in pre-colombian times, and many scientific investigations were carried out on the functional morphology and anatomy with regard to biomechanical adaptations of the found structures, no research focused on the branch-stem attachment. The most conspicuous features of such a ramification are the pronounced constrictions at the branch-stem junctions that are also present in the lignified vascular structures within the succulent cortex. Based on Finite Element Analyses of ramification models it could be demonstrated that these indentations in the region of high flexural and torsional stresses are not regions of structural weakness, e.g. allowing vegetative propagation. On the contrary, they can be regarded as anatomical adaptations to increase the stability by fine-tuning the stress state and stress directions in the junction along prevalent fiber directions. The development of the woody support structure within the succulent cortex of the parental shoot can be traced back to the leaf and bud traces of the dormant axillary buds. Surprisingly, these initials also develop into another woody structure supporting the flowers of the cacti. As these two support structures differ significantly in their macroscopic and microscopic anatomy and as they develop from the same initial state as leaf/bud traces, another objective of this work was to analyze the secondary growth of the two structures with traditional botanic investigation methods. The results of these investigations reveal a wood dimorphism consisting of an early parenchymatous phase followed later by fibrous wood in both kind of support structure. In vegetative branches, the woody support structures have the typical ringlike arrangement as found in the stele of the parental shoot, whereas the flower support structures have a reticular arrangement of interconnected woody strands. This fundamentally different anatomy of the support structures results from the formation of an interfascicular cambium between the leaf/bud traces when a vegetative branch forms or its absence in the case of a flower. After shedding light on the functional morphology and anatomy of the cactus ramification and their development the question arises if the found load adaptation strategies may serve to improve technical fiber composite structures analogue to the design recommendation developed from the biomechanical analyses of tree ramifications. Such a biomimetic transfer from the cactus ramification as biological role model to a technical implementation and the adaptation of the fine-tuned geometric shape and arrangement of lignified strengthening tissues might contribute to the development of alternative concepts for branched fiber-reinforced composite structures within a limited design space.

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Cornwall, Jonathan Edgar, and n/a. "The functional morphology of the human thoracolumbar transversospinal muscles." University of Otago. Department of Anatomy & Structural Biology, 2009. http://adt.otago.ac.nz./public/adt-NZDU20090615.144650.

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The thoracolumbar transversospinal muscles are vital in normal function and are implicated in the pathogenesis of different forms of spinal pathology and pain. They are the target for specific forms of clinical intervention such as exercise regimens and the release of �trigger points�, and are often analysed through imaging studies and electromyographic recordings. Despite the importance of these muscles, there is a paucity of knowledge in regard to aspects of their functional morphology. The aim of this thesis was to examine the thoracolumbar transversospinal muscles between the mid-thoracic spine and sacrum, examining their gross morphology, fibre arrangement, fibre types, and an animal model in order to provide a better understanding of their functional morphology. The gross morphology of these muscles was studied by micro-dissection of cadaveric material. Their form was found to differ from that published in either text book or peer reviewed articles, clearly indicating the existence of a �semispinalis� muscle in the lumbar spine. In addition, the arrangement of these muscles was found to be homologous between the thoracic and lumbar regions, which is contrary to published descriptions. Arrangement of the muscle fibres was examined by identifying motor endplates with acetylcholinesterase histochemistry in all muscles throughout the area of interest. Only one endplate per fibre was observed, and no in-series fibres were found. All muscles showed a complex multipinnate form with large areas of muscle tendon intruding into each muscle. Fibre type proportions in each muscle were investigated by immunohistochemistry. Results indicate the percentage of total muscle area occupied by type I fibres decreased the more caudad the vertebral level of origin, for all muscles. There were significant differences in the area percentage of type I fibres between many different vertebral levels. These differences were mostly found between the most cranial and most caudal levels examined. The percentage of type I fibres recorded suggest all muscles are likely postural in function, and the gradual decrease in type I fibres and the lack of a distinct thoracic / lumbar boundary in the data suggests the thoracic and lumbar transversospinal muscles are homologous. The thoracolumbar transversospinal muscles of the MLC3F nlacZ transgenic mouse were micro-dissected to determine their morphology, and their fibre arrangement subsequently determined using acetylcholinesterase histochemistry. These muscles showed a homogeneous form throughout the thoracolumbar spine, and no in-series muscle fibres were observed with all muscles having one motor endplate per fibre. Results indicated similarities between the morphology of mouse and human transversospinal muscles, perhaps indicative of an adaptation to an upright posture. This thesis provides information that facilitates a more complete understanding of the morphology and function of the thoracolumbar transversospinal muscles. In addition, results indicate that these muscles are homologous through the thoracic and lumbar spine, and therefore the classification and nomenclature used to describe these muscles should be re-examined. Furthermore, the morphological evidence, combined with recent embryological studies, supports the use of the term �spinotransverse� to more accurately describe this muscle group.

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O'Malley, Andrew Stephen. "A qualitative and quantitative investigation of the functional morphology of the juvenile scapula." Thesis, University of Dundee, 2013. https://discovery.dundee.ac.uk/en/studentTheses/f69db2ee-d94d-4e74-8b18-092ad44fe88a.

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This thesis presents a radiographic description of developmental morphology of the human scapula and a comprehensive morphological description of trabecular bone in the perinatal scapula. While the aim was originally to describe the changing trabecular morphology in the developing scapula, considerable thought has gone into the design, advancement and validity of the methodologies presented in this thesis. The work of previous studies has been considered and improved upon to take into account recent advances in software and hardware. Specifically, the introduction of MPR to the methodology has resulted in a more efficient and reliable technique that could allow future researchers to examine larger datasets in shorter periods of time. Additional anthropometric data were also gathered on the perinatal scapula, which was used to assist in the design of the multiplanar stereoscopic analysis. User error associated with threshold definition and VOI placement was also investigated and found to be negligible. With respect to development of the juvenile scapula, three distinct developmental phases, comprising eight separate groups, were identified from the radiographic study and anthropometric review study: pre-reboot (<0.5y), reboot (0.5-3y) and post-reboot (>3y). A clear pattern of regional organisation was visible at the earliest stages of development, echoing the findings of previous studies. It was suggested that the reboot phase represents a developmental period in which the scapula undergoes functional change under a two-tier mechanism, which influences its overall development. On one level the scapula appears constrained by a rigid template that controls macro- morphology in preparation for phylogenetically anticipated demands, which may, or may not, materialise; on a second tier is the adaptive micro-architecture that initially compliments the phylogenetic template, but retains the flexibility to respond to shifting ontogenetic demands. The trabecular architecture of the pre-reboot specimens was subsequently analysed in quantitative detail. A progressive radiating pattern, which originated from the approximate location of the primary ossification centre, was identified; it is suggested that a combination of radiating growth and internal vascular distribution are significant contributors to this pattern. This thesis provides a detailed account of the developmental morphology of the human scapula and contributes new elements to the evolving methodologies used in this field. The findings of this study also lay the foundation for further investigation of the radiating pattern of ossification and the potential for micro-architecture in developing bone to adapt to ontogenetic demands despite gross morphology that is phylogenetically constrained.

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Anemone, Robert Louis. "The functional morphology of the prosimian hindlimb : some correlates between anatomy and positional behavior /." Thesis, Connect to this title online; UW restricted, 1988. http://hdl.handle.net/1773/6506.

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Foster, Adam D. "The developmental origins and functional role of postcranial adaptive morphology in human bipedal anatomy." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/333343.

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When considering the array of terrestrial locomotor behaviors, bipedalism is a particularly rare way of moving about the landscape. In fact, humans are the only obligate terrestrial mammalian bipeds. Therefore, understanding both how and why it evolved is particularly intriguing. However, there is debate over why the evolution of bipedalism occurred and there is a large gap in knowledge for the mechanisms that underpin the evolution of these adaptive morphologies. One complicating factor for sorting out which models best explain how our hominin ancestors became bipedal is that they all rely on the same set of traits. Moreover, many of the traits that are thought to be diagnostic of bipedalism are only linked by association and have not been experimentally tested. That is, they do not appear in non-human primates and other quadrupeds. Therefore, addressing why the evolution of bipedalism occurred requires understanding the adaptive significance of traits linked with bipedalism. In this dissertation, I use an experimental approach employing both human and animal models to explore links between morphology and behavior and to tease apart the adaptive significance of particular traits. For the human portion of the dissertation, I use an inverse dynamics approach (estimating muscle forces from kinematic, kinetic, and anatomical data) to determine how modern human anatomy functions while walking using ape-like postures to clarify the links between morphology and energy costs in different mechanical regimes to determine the adaptive significance of postcranial anatomy. The results from this portion of the dissertation suggest that adopting different joint postures results in higher energy costs in humans due to an increase in active muscle volumes at the knee. These results lead to two conclusions important for understanding the evolution of human bipedalism. One is that human anatomy maintains low energy costs of walking in humans compared to chimpanzees regardless of lower limb postures. Second, the results suggest that erect trunk posture may be an important factor in reducing energy costs, therefore indicating that lumbar lordosis (the curvature of the lower spine) is important for reducing costs. For the animal portion of the dissertation, I use rats as a model for the quadrupedal-to-bipedal transition and experimentally induce bipedal posture and locomotion under a variety of loading conditions to determine if traits consistent with the evolution of bipedalism occur and under what conditions. This experimental design also has the ability to determine if there is a role for developmental plasticity in generating bipedal morphology to help answer the question how the evolution of bipedalism occurred. I find that inducing bipedal behaviors in a quadrupedal animal generates morphology consistent with human bipedal traits and that loading conditions have specific effects in different skeletal elements and at particular joints. I also find that there is a plausible role for developmental plasticity in generating adaptive bipedal morphology in the earliest hominins. Overall, the results from the experimental procedures in this dissertation were able to clarify links between behavior and bipedal morphology, demonstrate a plausible role for developmental plasticity in early adaptation to bipedal behavior in australopiths, determine the adaptive significance of human postcranial anatomy, and the ways in which postcranial anatomy reduces costs.

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Holloway, Waymon L. "Comparative Cranial Ecomorphology and Functional Morphology of SemiaquaticFaunivorous Crurotarsans." Ohio University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1542230980102513.

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McGroarty, James Roy. "Comparative morphology and functional anatomy of the digestive tract of the copepods Tigriopus californicus and Calanus plumchrus : a light and electron microscope study." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/24853.

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A study of the digestive tract of the copepods Tigriopus californicus and Calanus plumchrus was carried out using techniques of light and electron microscopy. In Tigriopus californicus, the foregut contains a curved cuticle lined esophagus which extends from the ventral mouth to the junction of the anterior midgut and midgut caecum. The noncuticulized portion of the digestive tract consists of: 1. A single spherical midgut caecum located anteriorly, 2. An anterior midgut, 3. A posterior midgut. There are cuticulized anterior and posterior hindgut regions ending in a dorsal anus. In Calanus plumchrus, the foregut consists of a cuticle lined esophagus extending from the ventral mouth to the junction of the midgut and the midgut diverticulum. The noncuticulized portion of the digestive tract consists of: 1. A single midgut diverticulum, 2. A midgut that is divisible on the basis of epithelial cell type and function. There is a long abruptly narrowing cuticle lined hindgut ending in an anus. In Tigriopus californicus, four cell types could be distinguished and from such ultrastructural characteristics as the position in the digestive tract, abundance, position, and type of organelles, lipid content, presence and type of vesiculation, and electron density, functions for the cells were determined. Cell type '1' is an embryonic 'stem' cell. It functions as a replacement cell and differentiates when cells are worn away or lost in secretion. Cell type '2' is mainly a secretory cell and functions in the synthesis of proteins. It also plays a role in lipid absorption. Cell type '3' is absorptive, mainly for lipids. Cell type M1, found only in the anterior midgut is also an absorptive cell. The presence of electron dense vesicles suggests that lipid absorption is not its major function. From the abundance of cell type and from examination of the ultrastructure in the various regions of the digestive tract, the following conclusions were made: 1. The midgut caecum functions in the absorption of digested nutrients. 2. The anterior midgut plays a role in nutrient absorption but is important in secretion. 3. The posterior midgut cells are mainly absorptive. In Calanus plumchrus, five cell types could be distinguished. Cell type 'E' is an undifferentiated 'stem1 cell. Cell type 'R' found in the midgut diverticulum and posterior midgut regions, is absorptive. Its developed basal surfaces suggest a transport function between the cell and the haemo-coel . Cell type 'D' is found in the glandular region of the midgut and is absorptive. It has an ultrastructure similar to that observed for cell type 'R'. Cell type 'B' is a large vacuolated absorptive cell found in the glandular region of the midgut. Cell type 'F' functions in the synthesis and secretion of digestive enzymes. In Calanus plumchrus, the midgut diverticulum is specialized for the absorption of digested nutrients and transport of metabolites to the haemocoel . The anterior midgut regions are mainly absorptive. It includes a vacuolated glandular region specialized for pinocytotic absorption. In the middle section of the midgut, adjacent and posterior to the glandular region, is an area of epithelial cells specialized for secretion. The posterior midgut regions are mainly absorptive. In Tigriopus californicus biological markers can be used to determine cell type function in correlation with the observed ultrastructure.
Science, Faculty of
Zoology, Department of
Graduate

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Fox, Maria. "Neandertal Lumbopelvic Anatomy and the Biomechanical Effects of a Reduced Lumbar Lordosis." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1378109007.

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Davis, Jillian S. "Functional Morphology of Mastication in Musteloid Carnivorans." Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1405694251.

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Santos, Camila Mayumi Hirata dos. "Estudo comparativo da musculatura associada à alimentação entre as raias-viola Rhinobatos percellens e Zapteryx brevirostris (Chondrichthyes, Rhinobatidade) /." Rio Claro : [s.n.], 2010. http://hdl.handle.net/11449/99522.

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Orientador: Otto Bismarck Fazzano Gadig
Banca: Roberto Goitein
Banca: Ulisses Leite Gomes
Resumo: neurocrânio de duas espécies de raias-viola, Rhinobatos percellens e Zapteryx brevirostris. Os exemplares foram coletados na plataforma continental de São Paulo, junto à frota artesanal e industrial. Os indivíduos foram dissecados frescos, com descrição de sete regiões do neurocrânio, e origem, inserção e tamanho relativo dos músculos: epaxialis, quadratomandibularis, preorbitalis, levator palatoquadrati, depressor mandibularis, levator hyomandibularis, depressor hyomandibularis, levator rostri, coracomandibularis, coracohyoideus e coracohyomandibularis. Não foram verificadas diferenças ontogenéticas ou sexual do neurocrânio e musculatura. O apêndice rostral possui diferenças no formato e número de fenestras entre R. percellens e Z. brevirostris. O rostro é mais extenso em R. percellens e existe um par de extensões cartilaginosas no apêndice rostral, semelhantes a barbilhões que não são encontrados em Z. brevirostris. As cápsulas nasais de R. percellens são arqueadas anteriormente. A crista supra-orbital é bem desenvolvida e são observados processos pré e pós-orbitais nas duas espécies. A fontanela posterior é grande e em formato de gota em R. percellens, e em Z. brevirostris ela não é presente em todos os exemplares. Na região latero-posterior da cápsula ótica está a faceta articular da hiomandíbula, que é mais extensa em Z. brevirostris. Na região posterior do crânio está o forâmen magno e em suas laterais estão os côndilos occipitais, mais largos em Z. brevirostris. A musculatura cefálica das duas espécies é semelhante, apresentando diferenças principalmente quanto ao comprimento de tendões, posição de algumas inserções e proporções dos músculos, com exceção do depressor hyomandibularis que possui inserção dividida, ambas na hiomandíbula em Z. brevirostris, e uma na hiomandíbula e outra na primeira cartilagem... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: This study describes and compares the musculature related to feeding and the neurocranium of two species of guitarfishes, Rhinobatos percellens e Zapteryx brevirostris. The specimens were caught by artisanal and commercial fisheries along the São Paulo continental shelf, southeast Brazil. The specimens were dissected fresh with the description of seven regions of the neurocranium, and origin, insertion and relative size of the muscles: epaxialis, quadratomandibularis, preorbitalis, levator palatoquadrati, depressor mandibularis, levator hyomandibularis, depressor hyomandibularis, levator rostri, coracomandibularis, coracohyoideus, and coracohyomandibularis. No ontogenetic or sexual differences were observed in neurocranium and musculature for both species. The rostral appendix has differences in shape and fenestra number between R. percellens and Z. brevirostris. The rostral cartilage is more extensive in R. percellens in which there is a par of cartilaginous extensions in the rostral appendix, like barbels, not found in Z. brevirostris. The nasal capsules of R. percellens are anteriorly oriented. The supra-orbital crest is well developed and there is pre and post-orbital process in both species. The posterior fontanelle is wide and bead shaped in R. percellens, and is not found in all the specimens of Z. brevirostris. The hyomandibular facet is longer in Z. brevirostris. On the posterior region of the neurocranium there is the foramen magnum, and on each side the occipital condily, that are larger in Z. brevirostris. The cranial musculature of both species is similar, they have differences concerning the size of tendons, position of some insertions and proportion of the muscles, except for depressor hyomandibularis which originates on the superficial hypobranchial raphe and has two insertions, both on hyomandibula in Z. brevirostris, while in R. percellens there is one... (Complete abstract click electronic access below)
Mestre

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Stinson, Charlotte M. "Functional Trade-offs in Feeding Performance in Salamanders of the Family Salamandridae." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6956.

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Performance is an organism’s ability to accomplish a particular task or behavior, and morphology can have a major impact on the performance of an organism. Salamanders are ecologically diverse and can feed using a variety of behaviors depending on the environment in which feeding occurs. Feeding is accomplished through the use of the hyobranchial apparatus, which lies along the oropharynx, and this structure can have competing roles; in aquatic environments the apparatus is used for suction feeding and works to depress the floor of the mouth, but during terrestrial feeding this structure projects the tongue forward out of the mouth. Diverse morphologies of the hyobranchial apparatus enable varying degrees of feeding performance, both in aquatic and terrestrial environments. For my dissertation I have investigated the interactions, and possible functional trade-offs, of feeding morphology and performance in salamanders of Family Salamandridae. These salamanders are an ideal system for studying the interactions of morphology and performance across different environments because they have diverse ecology, being either fully aquatic, semi-aquatic, or terrestrial as adults, as well as differences in hyobranchial apparatus morphology. In these studies I have quantified the morphology and performance of seven salamandrid species feeding in aquatic (Chapter 2) and terrestrial (Chapter 3) environments to assess the links between these two parameters, as well as investigated the evolutionary patterns of feeding morphology, performance, and behavior across the Salamandridae (Chapter 4) to better understand the co-evolution of these traits across water-land transitions. During aquatic feeding salamanders use rapid mouth opening and hyobranchial depression to expand the oropharynx and generate negative pressure, and fluid flow, into the mouth. I hypothesized that more robust hyobranchial apparatus would yield increased aquatic feeding performance in salamandrids. When compared to semi-aquatic newts, the fully aquatic species, Paramesotriton labiatus, had greater mineralization of the hyobranchial apparatus, as well as relatively narrower basibranchial and wider ceratobranchial I + II complexes. These morphological differences coincide with greater aquatic feeding performance. Kinematics from high-speed videography revealed that maximum mouth opening velocities and accelerations were approximately two and five times greater, respectively, in Paramesotriton, and hyobranchial depression acceleration was found to be approximately three times greater than in the semi-aquatic species Pleurodeles, Notophthalmus, Triturus, and Cynops. Using digital particle image velocimetry, peak and average fluid velocities generated in Paramesotriton during suction feeding events were found to be 0.5 m s-1 and 0.2 m s-1, respectively, doubling that of all semi-aquatic species. These findings reveal that specialized morphology increases aquatic feeding performance in a fully aquatic newt. Salamanders use the hyobranchial apparatus and its associated musculature for tongue projection during terrestrial feeding. Hyobranchial apparatus composition and morphology vary across species and different morphologies are better suited for feeding in aquatic versus terrestrial environments. I hypothesized that differences in hyobranchial apparatus morphology and function result in functional trade-offs in feeding performance. Specifically I predicted that semi-aquatic and aquatic salamandrids with hyobranchial morphology suited for aquatic feeding would have lower performance, in terms of tongue-projection distance, velocity, acceleration and power, compared to terrestrial salamandrids when feeding in a terrestrial environment. I found that semi-aquatic and aquatic newts had lower tongue projection performance when compared to the terrestrial salamanders Chioglossa lusitanica and Salamandra salamandra. The fully aquatic newt, Paramesotriton labiatus, has a robust, heavily mineralized hyobranchial apparatus and was unable to project its tongue during terrestrial feeding, and instead exhibited suction-feeding movements better suited for aquatic feeding. Conversely, terrestrial species have gracile, cartilaginous hyobranchial apparatus and enlarged tongue pads that coincided with greater tongue-projection distance, velocity, acceleration, and power. Chioglossa exhibited extreme tongue-projection performance, similar to that seen in elastically projecting plethodontid salamanders; muscle-mass-specific power of tongue projection exceeded 2200 W kg-1, more than 350 times that of the next highest performer, Salamandra, which reached 6.3 W kg-1. These findings reveal that two fully terrestrial salamandrids have morphological specializations that yield greater tongue-projection performance compared to species that naturally feed in both aquatic and terrestrial environments. Salamanders of the Salamandridae that feed in both aquatic and terrestrial environments employ different behaviors depending on the environment. Using phylogenetic comparative methods, I assessed the relationships between feeding morphology, kinematics, and performance, and the ecology and feeding behavior of salamandrids. I also examined the co-evolution of feeding morphology and performance within Family Salamandridae. Behavior appears to co-evolve with feeding musculature, velocity of feeding movements, and fluid velocity produced during aquatic feeding. Flow velocity produced during aquatic feeding was related to the cross-sectional area of the rectus cervicis muscles, which rapidly depress the hyobranchial apparatus during suction feeding. Salamandrids with greater cross-sectional area of these depressor muscles generate faster flow velocity in aquatic feeding. Conversely, the evolution of hyobranchial apparatus morphology is more closely linked to ecology than to behavior. These findings indicate that both behavior and ecology are important for understanding the evolution of morphology and feeding performance across Family Salamandridae.

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17

Santos, Camila Mayumi Hirata dos [UNESP]. "Estudo comparativo da musculatura associada à alimentação entre as raias-viola Rhinobatos percellens e Zapteryx brevirostris (Chondrichthyes, Rhinobatidade)." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/99522.

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Made available in DSpace on 2014-06-11T19:30:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-02Bitstream added on 2014-06-13T19:18:44Z : No. of bitstreams: 1 santos_cmh_me_rcla.pdf: 2185651 bytes, checksum: c876eb5b088cd7609fb2acb4078a1d09 (MD5)
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neurocrânio de duas espécies de raias-viola, Rhinobatos percellens e Zapteryx brevirostris. Os exemplares foram coletados na plataforma continental de São Paulo, junto à frota artesanal e industrial. Os indivíduos foram dissecados frescos, com descrição de sete regiões do neurocrânio, e origem, inserção e tamanho relativo dos músculos: epaxialis, quadratomandibularis, preorbitalis, levator palatoquadrati, depressor mandibularis, levator hyomandibularis, depressor hyomandibularis, levator rostri, coracomandibularis, coracohyoideus e coracohyomandibularis. Não foram verificadas diferenças ontogenéticas ou sexual do neurocrânio e musculatura. O apêndice rostral possui diferenças no formato e número de fenestras entre R. percellens e Z. brevirostris. O rostro é mais extenso em R. percellens e existe um par de extensões cartilaginosas no apêndice rostral, semelhantes a barbilhões que não são encontrados em Z. brevirostris. As cápsulas nasais de R. percellens são arqueadas anteriormente. A crista supra-orbital é bem desenvolvida e são observados processos pré e pós-orbitais nas duas espécies. A fontanela posterior é grande e em formato de gota em R. percellens, e em Z. brevirostris ela não é presente em todos os exemplares. Na região latero-posterior da cápsula ótica está a faceta articular da hiomandíbula, que é mais extensa em Z. brevirostris. Na região posterior do crânio está o forâmen magno e em suas laterais estão os côndilos occipitais, mais largos em Z. brevirostris. A musculatura cefálica das duas espécies é semelhante, apresentando diferenças principalmente quanto ao comprimento de tendões, posição de algumas inserções e proporções dos músculos, com exceção do depressor hyomandibularis que possui inserção dividida, ambas na hiomandíbula em Z. brevirostris, e uma na hiomandíbula e outra na primeira cartilagem...
This study describes and compares the musculature related to feeding and the neurocranium of two species of guitarfishes, Rhinobatos percellens e Zapteryx brevirostris. The specimens were caught by artisanal and commercial fisheries along the São Paulo continental shelf, southeast Brazil. The specimens were dissected fresh with the description of seven regions of the neurocranium, and origin, insertion and relative size of the muscles: epaxialis, quadratomandibularis, preorbitalis, levator palatoquadrati, depressor mandibularis, levator hyomandibularis, depressor hyomandibularis, levator rostri, coracomandibularis, coracohyoideus, and coracohyomandibularis. No ontogenetic or sexual differences were observed in neurocranium and musculature for both species. The rostral appendix has differences in shape and fenestra number between R. percellens and Z. brevirostris. The rostral cartilage is more extensive in R. percellens in which there is a par of cartilaginous extensions in the rostral appendix, like barbels, not found in Z. brevirostris. The nasal capsules of R. percellens are anteriorly oriented. The supra-orbital crest is well developed and there is pre and post-orbital process in both species. The posterior fontanelle is wide and bead shaped in R. percellens, and is not found in all the specimens of Z. brevirostris. The hyomandibular facet is longer in Z. brevirostris. On the posterior region of the neurocranium there is the foramen magnum, and on each side the occipital condily, that are larger in Z. brevirostris. The cranial musculature of both species is similar, they have differences concerning the size of tendons, position of some insertions and proportion of the muscles, except for depressor hyomandibularis which originates on the superficial hypobranchial raphe and has two insertions, both on hyomandibula in Z. brevirostris, while in R. percellens there is one... (Complete abstract click electronic access below)

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Riddell, Clinton D. "Functional Morphology of the Vestibular End Organs in the Red-eared Slider Turtle, Trachemys scripta elegans." Ohio University Honors Tutorial College / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ouhonors1400600303.

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Sartori, André Fernando. "Anatomia do bivalve antártico Thracia meridionalis Smith, 1885 (Anomalodesmata: Thraciidae)." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/41/41133/tde-19092004-192817/.

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Thraciidae é uma das famílias de Anomalodesmata menos estudadas, dentre as quatorze que compõem a subclasse. Das cerca de trinta espécies atribuídas à família, apenas Trigonothracia jinxingae teve sua biologia e anatomia examinadas em detalhes; para outros Thraciidae, há pouca ou nenhuma informação morfológica, o que dificulta o entendimento das relações filogenéticas dentre os Anomalodesmata. Thracia meridionalis, única representante da família em águas antárticas, é aqui analisada sob o ponto de vista da anatomia, buscando iniciar o entendimento da biologia da espécie, bem como aprofundar os conhecimentos acerca do gênero Thracia e família Thraciidae, indispensáveis para a elucidação das relações evolutivas dentre os Anomalodesmata. A investigação detalhada da concha, sifões, e das estruturas e órgãos que compõem a cavidade palial e massa visceral foi realizada utilizando-se técnicas de dissecção, histologia e microscopia eletrônica de varredura. A concha é fina, inequivalve, ornamentada por grânulos periostracais calcificados, e dotada de charneira edêntula, ligamento secundário e primário, este último com litodesma presente apenas em indivíduos jovens. O manto tem margens extensivamente fundidas, com curta abertura pediosa, quarta abertura palial reduzida e sifões longos, separados, originando-se exclusivamente das pregas internas; as glândulas hipobranquiais são assimétricas, porém restritas à câmara infra-branquial, o que distingue T. meridionalis dentre os Anomalodesmata. Os ctenídios são extensos, heterorrábdicos e do tipo E de Atkins; uma ampla abertura entre os eixos dos ctenídios e o septo que separa as aberturas proximais dos sifões permite a comunicação entre as câmaras infra e supra-branquiais. A associação entre os palpos labiais e ctenídios pertence à categoria III de Stasek, e os estatocistos são do tipo B3 de Morton, este tipo constituindo novo registro para os Thracioidea. O estômago do tipo IV na classificação de Purchon é extensivamente provido de áreas de triagem, sugerindo que o animal ingere grande quantidade de partículas, o que é corroborado pelo intestino freqüentemente dilatado e repleto de fezes. T. meridionalis é hermafrodita simultâneo, com gônadas, gonodutos e gonóporos distintos. Grandes ovócitos (~200 µm) protegidos por espessa membrana vitelínica, e razão próxima de 0,75 entre os comprimentos das prodissoconchas I e II são indicativos de desenvolvimento larval lecitotrófico.
The functional morphology of the Thraciidae is sparsely understood. Though several of its members had some morphological aspect described, only Trigonothracia jinxingae from Chinese waters is known in details, Thracia meridionalis being the first austral thraciid to be comprehensively reported upon. The latter species is the only representative of the family in Antarctic waters, and a common mud-dweller in the Admiralty Bay, King George Island, where living specimens were collected for the present study. T. meridionalis shares with Trigonothracia jinxingae many features that are typical of most Anomalodesmata: a secondary ligament of fused periostracum; extensively fused mantle margins; ctenidia of type E; ctenidial-labial palp junction of category III; stomach of type IV and simultaneous hermaphroditism. However, T. meridionalis is strikingly different from Trigonothracia in a number of aspects, as the presence of a fourth pallial aperture; statocysts of type B3; heterorhabdic ctenidia; a direct communication between the mantle chambers; deep-burrowing habit, the specimens lying on the left shell valve; siphons often retracted away from the sediment surface, protected within their mucous-lined burrows; stomach with extensive sorting areas; suspension-feeding habit; rectum passing over the kidneys and separate male and female gonadial apertures, thus revealing a greater diversity of form within the Thraciidae than is currently known.

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Chapman, Tara. "Morphometric, functional and biomechanical analysis of a virtual Neandertal in comparison with anatomically modern humans." Doctoral thesis, Universite Libre de Bruxelles, 2017. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/251406.

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Early anthropological examination of Neandertal skeletal material by Marcellin Boule gave rise to popular images of Neandertals as brutish, ape-like creatures who walked hunched over with bent knees and a shuffling gait. Today, it is generally thought that Neandertals moved in a similar manner to humans with locomotive patterns within human ranges of variation and a bipedal gait likely to be indistinguishable from that of modern humans However, this hypothesis has not been tested by using the Neandertal skeleton as a whole. There is no complete Neandertal skeleton in the fossil record. The aim of this thesis was to reconstruct a complete virtual skeleton of a Neandertal based on the Spy II remains for educational museology purposes and for biomechanical analysis. Comparative analyses of Neandertal and modern human bones (pelvis, femur, rib) using different reference populations from Belgium were also undertaken. These studies were performed with a view to further understanding Neandertal bone morphology in comparison to modern humans, to assist in the reconstruction of the Neandertal Spy II skeleton and to aid in biomechanical analysis. A study on the sex determination of the pelves showed that there was no difference between physical linear measurements and virtual measurements, which was an important validation. The lhpFusionBox musculoskeletal software, which was developed at ULB, was used to scale available Neandertal and modern human bones to reconstruct the skeleton. Previous methods in the literature have only scaled bones of the same nature. A novel and validated scaling method was used to scale the Kebara 2 pelvis to the dimensions of the Spy II femur (as Spy II only has a small piece of sacrum) via the Neandertal 1 femur and pelvis. The reconstruction of a complete Neandertal skeleton based on the Spy II remains enabled the validation of individual reconstructions of bones, reconstructed long bones to be compared together with other limb proportions of Neandertals, stature estimation to be performed, and questions to be asked on previous attributions of bones to Spy II. The thoracic shape of Neandertals has previously been subject to much debate with many authors stating that it would have been markedly different from modern humans. This thesis created a Neandertal thorax with assistance from rib and thoracic experts from different domains using the Kebara 2 remains. One reconstruction was found to have a similar shape to modern humans and the other a markedly different shape, highlighting difficulties in thoracic reconstruction of fossil hominids.The full scale Neandertal skeleton has been printed in 3D and used in RBINS and other Museums in Europe as a reference for the Neandertal Skeleton in permanent gallery exhibitions. This skeleton is also used as the base for Neandertal hyper-realistic artistic reconstructions based on scientific evidence by the artists, the Kennis brothers which are in the Centre d'Interprétation de l'Homme de Spy, the National History Museum, London and other museums around the world. The reconstruction of a complete lower limb also allowed biomechanical studies. The various biomechanical studies have looked at what happens when you fuse the motion of a living modern human to Neandertal bones. We cannot say that the Neandertal would have walked or squatted similar to the volunteers in the studies but we can say that the morphology of their bones would have enabled them to walk or squat in this way. All the moment arms of the major muscles of the hip and knee were analysed and it was demonstrated that the Neandertal models largely had greater muscle moment arms than the AMH models meaning Neandertals could have had a significant mechanical advantage over modern humans. These studies demonstrate Neandertal postcranial morphology can be different to modern humans although certain aspects may be more similar than previously thought.
Historiquement, le travaux de Marcellin Boule ont donné lieu à des représentations populaires de Néandertaliens vus comme des créatures simiesques bestiales qui se déplaçaient courbés avec des genoux pliés en traînant les pieds. Aujourd'hui, il est généralement admis que les Néandertaliens se déplaçaient d'une manière similaire à l'homme moderne avec une locomotion bipède. Toutefois, cette hypothèse n'a pas été encore testée sur un squelette néandertalien dans son ensemble. Comme il n’existe aucun squelette de Néandertalien entier, le but de cette thèse était de reconstituer un squelette virtuel complet sur la base des restes de Spy II à des fins éducatives de muséologie et pour l'analyse biomécanique.Des analyses comparatives d’os de Néandertalien et d’humains modernes (bassin, fémur, côtes) en utilisant diverses populations de référence de Belgique ont également été menées. Ces études ont été réalisées en vue de comprendre la morphologie néandertalienne, pour aider à la reconstruction du squelette Spy II et à l'analyse biomécanique. Une étude sur la détermination du sexe à partir des pelvis a montré qu'il n'y avait pas de différence entre les mesures linéaires physiques et les mesures virtuelles, ce qui était une validation importante.Le logiciel musculosquelettique lhpFusionBox, développé à l'ULB, a été utilisé pour reconstruire le squelette. Un nouveau procédé de mise à l'échelle validé a été utilisé pour mettre à l'échelle le bassin de Kebara 2 aux dimensions du fémur de Spy II (comme Spy II ne possède qu’un petit fragment de sacrum) via le fémur et le bassin de Neandertal 1. La reconstruction d'un squelette complet de Néandertalien a apporté de nouvelles connaissances sur cette espèce dans différents domaines. Elle a permis la validation des reconstructions individuelles des os, de comparer les os longs reconstruits avec d'autres proportions des membres de Néandertaliens, de faire une estimation de stature, et de reconsidérer les attributions antérieures d'os à Spy II. La forme thoracique des Néandertaliens a déjà fait l'objet de nombreux débats. Cette reconstruction de Spy II, creé avec l'aide des experts utilisant les restes de Kebara 2, montre deux formes de reconstruction differentes, et indique les difficultés de la reconstruction thoracique des fossiles. Le squelette virtuel complet a été imprimé en 3D et utilisé par l’IRSNB et d'autres musées en Europe comme une référence de squelette néandertalien. Ce squelette a également été utilisé comme base pour les reconstructions artistiques hyper-réalistes de Néandertaliens, basées sur des données scientifiques, par les artistes Kennis et sont présentés dans les musées du monde entier. La reconstruction d'un membre inférieur complet a également permis des études biomécaniques. Ces dernières ont étudié la fusion du mouvement d'un homme moderne actuel avec des os néandertaliens. On ne peut pas se prononcer si le Néandertalien marchait ou s’accroupissait de manière similaire aux hommes modernes, mais on peut affirmer que leur morphologie osseuse leur permettait de marcher ou de s’accroupir de cette façon. Tous les bras de levier des principaux muscles de la hanche et du genou ont été analysés et il a été démontré que les Néandertaliens avaient les bras de levier plus grand que le modèle homme moderne signifiant Néandertaliens auraient eu un avantage mécanique important. Cette études démontre que des aspects de la morphologie postcrânienne néandertalienne soient différents, bien que certains d’entre eux soient plus semblables aux humains modernes qu'on ne le pensait.
Doctorat en Sciences biomédicales et pharmaceutiques (Médecine)
info:eu-repo/semantics/nonPublished

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Garner, Austin Michael. "Examining the Relationships between Form, Function, Environment, and Behavior in Adhesive Pad-bearing Lizards." University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1626363948177358.

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Tissandier, Sylvie. "Evolution of modular morphology in actinopterygian pectoral fins." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101658.

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With a generally conserved function for locomotion, paired fins have an extensive evolutionary history that has resulted in highly disparate morphologies in a wide diversity of taxa. Two-dimensional geometric morphometrics offers a means to quantitatively describe disparity and changes in the shape of pectoral fins. Actinopterygians lend themselves well to a study of this nature due to their prolific diversity and prevalence in the fossil record. As a result of changes in skeletal fin structures and the lack of homologous elements throughout the group, three morphological modules are used as the unit of comparison rather than individual elements of the fin. Ordination plots from thin plate spline analyses, including fossil and extant taxa, show correspondence with the actinopterygian phylogeny as trends become apparent through the group. Basal actinopterygians and basal teleosts tend to have a narrow, elongate fin shape. Following a shift in morphospace, derived teleosts have a wider fin base, with an elongate anterior margin of the fin relative to the posterior trailing edge. Linear and squared-change parsimony reconstructions of continuous data allow the phylogeny to be traced through morphospace to approximate the path of pectoral fin evolution. The shift in morphospace occurs at Acanthomorpha, and is correlated with the evolution of a physoclistous swim bladder and a change in the position and orientation of pectoral fins. As a result of these changes, new swimming modes are made available, and the expansion of locomotory modes of Acanthomorpha is here hypothesized to be associated with a sharp increase in pectoral fin disparity.

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Bemis, Katherine Elliott. "Studies On The Anatomy Of Teleosts." W&M ScholarWorks, 2020. https://scholarworks.wm.edu/etd/1593091444.

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The Longnose Lancetfish, Alepisaurus ferox, is a pelagic marine fish that has a heterodont dentition, including large fangs on both the upper and lower jaws. Their diet is well documented and includes salps, hyperiid amphipods, pelagic polychaete worms, mesopelagic fishes, and cephalopods. However, the function of the heterodont dentition, the structure of the teeth, and replacement mode is largely unknown. We studied a series of A. ferox to describe their dentition and tooth replacement. All teeth are replaced extraosseously. Palatine and dentary fangs develop horizontally in the oral epithelium on the lingual surface of dentigerous bones. Developing fangs rotate into place and attach to the bone through a pedicel that forms at the base of each tooth on the lingual side of the dentigerous bone. We compare extraosseous horizontal tooth replacement and rotation of large fangs in A. ferox to examples of other teleosts rotation of fangs. Atlantic Cutlassfish, Trichiurus lepturus, have large, barbed premaxillary and dentary fangs and sharp, dagger-shaped teeth in their oral jaws. We used dry skeletons, histology, SEM, and micro-CT scanning to study T. lepturus to describe its dentition and tooth replacement. We identified and described three modes of intraosseous tooth replacement in T. lepturus depending on the location of the tooth in the jaw. Such distinct modes of tooth replacement in a teleostean species are unknown. We compared modes of replacement in T. lepturus to 20 species of scombroids to explore the phylogenetic distribution of these three replacement modes. Our study highlights the complexity and variability of intraosseous tooth replacement and that developmentally different tooth replacement processes can yield remarkably similar dentitions. We review literature on the comparative anatomy of Ocean Sunfishes (Molidae) and presents new findings based on our studies. We document similarities and differences among the three living genera, Ranzania, Masturus, and Mola using an organ system approach to examine: general body form and external anatomy; skeleton; integument; brain and sense organs; digestive organs; heart and circulation; respiratory system; excretory system; and endocrine organs. Molids have many anatomical specializations such as the formation of the clavus from dorsal- and anal-fin elements, enlarged gills with unusual skeletal supports, a heart with thick walls and more valves than other teleosts, ontogenetic loss of the swimbladder, enlarged kidneys and a well-developed urinary bladder, reduced otoliths, and a spinal cord contained completely within the braincase. Tagging studies on locomotion and diving behavior demonstrate that molids move efficiently over horizontal and vertical distances in the water column, and this new information helps to interpret the many unusual features of molid anatomy.

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Eno, Nancy Clare. "Functional morphology of cephalopod gills." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276579.

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Nobles, Mia S. "Nobles-Pecora dissection manual of human anatomy." Thesis, California State University, Long Beach, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10134002.

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This manual was written specifically as a guide for the beginner dissector to complete a prosected cadaver that will serve as an effective teaching and learning tool. The dissections are written in a manner that facilitates the preservation of more superfi- cial structures on the right side of the cadaver and deeper structures that otherwise would have been concealed on the left side of the cadaver. This format is ideal for students learning anatomy for the first time, as multiple planes can be compared on the same cadaver. The level of structures dissected and identified in these chapters was established with the understanding that the dissector’s knowledge of human anatomy is at the level of completion of a general undergraduate anatomy survey course.

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Reynolds, David John Morton. "Functional anatomy and neuropharmacology of emesis." Thesis, University of Oxford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335848.

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Ostergaard, Pia. "The family chondracanthidae (crustacea, copepoda) : anatomy, morphology and phylogeny." Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415459.

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Dinkele, Elizabeth. "Ancestral variation in mid-craniofacial morphology in a South African sample." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29166.

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Ancestry estimation is a critical component of the demographic profile compiled by forensic anthropologists when unknown skeletal remains are discovered. The mid-craniofacial region is most frequently used to estimate ancestry as this region reflects the genetic and morphological ancestry of an individual. The diverse composition of the South African population makes ancestry estimation problematic, and necessitates the development of reliable, population-specific standards. This study sought to characterise variations in mid-craniofacial shape and size between South Africans of European ancestry (EA), African ancestry (AA) and Mixed ancestry (MA). Metric, nonmetric and geometric morphometric assessments were performed on 392 crania from skeletal collections in South Africa. Variations in mid-craniofacial shape and size were assessed in the orbital, nasal, zygomatic and maxillary regions in two-and three-dimensions. Univariate and multivariate statistical analyses were employed to characterise variation and estimate ancestry in AA, MA and EA individuals. Multivariate analyses suggest that tightly integrated ancestral variations in each component of the mid-craniofacial region are associated with functional, regional and developmental proximities of these regions. Specifically, AA individuals exhibited wider and shorter midfacial regions than EA individuals, who exhibited the narrowest orbital, zygomatic and nasal breadths and the longest upper facial, orbital and nasal heights. EA individuals exhibited inferiorly-angled orbits, elongated nasal apertures and anteriorly projecting nasal bridges. Rounder nasal apertures, less anteriorly projecting nasal bridges and more anteriorly projecting maxillary regions were detected in AA individuals. MA individuals exhibited heterogeneity in terms of craniofacial shape and size, and therefore produced the lowest ancestry estimation accuracies. Overall, nasal and maxillary regions were the most ancestrally diverse regions. Antemortem maxillary tooth loss and midfacial trauma were confounding factors in ancestry estimation accuracies. The lowest ancestry estimation accuracies were yielded by two-dimensional metric (27%-60.2%) and nonmetric (57.1%-82.4%) methods. Metric and geometric morphometric assessments yielded the highest repeatability (≥ 95%) indicating that these methods may be more reliable for use in medicolegal contexts. Geometric morphometric shape assessments yielded the highest ancestry estimation accuracies (75-97.9%), suggesting the presence of three dimensional shape variations between ancestry groups. These results suggest that a continuum of ancestral variation, with large areas of overlap, exists across South African populations and emphasises the need to develop multivariate ancestry estimation standards which can estimate ancestry reliably.

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Sälgeback, Jenny. "Functional Morphology of Gastropods and Bivalves." Doctoral thesis, Uppsala University, Department of Earth Sciences, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7424.

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Functional morphology analyzes the relationships between form and function in organisms. However, a comprehensive analysis of any organic structure requires an integrated approach to morphology. For this purpose constructional morphology was developed, where function, phylogeny and construction together explain form. This thesis investigates functional and constructional aspects of gastropods and bivalves; two groups of molluscs which are among the most common shell-bearing invertebrates. Their shell protects the soft parts and different morphologic specializations enhance this function. Morphology and mode of life are often closely coupled.

Comparison of the distantly related cardiid bivalves Cardium costatum and Budmania spp. reveals similar shell modifications. Both have prominent keels functional in anchoring the shell within the sediment. The straight keels in C. costatum indicate an additional strengthening function, whereas the keels in Budmania spp. often are deformed and do not. Other shell modifications include secondary resorption of shell material and hollow keel interiors, reducing shell weight. These similarities are explained by parallel evolution and a common cardiid Bauplan.

Morphological shell characters in cerithiform gastropods have evolved independently in different taxonomic groups and multiple times within the same group. Shell characters are adaptive within five functional areas: defence from shell-peeling predators, burrowing and infaunal life, clamping, stabilization, and righting of the shell. Most characters are made feasible by determinate growth and a count-down programme.

In most environments predators that crush, peel and bore shells are present. As bivalves and gastropods grow by marginal accretion, and are able to replace lost shell material, traces of unsuccessful predation are preserved as scars. Experiments on the snail Nucella lamellosa show that repaired shells are just as strong as shells without damage. However, new scars follow old scar lines in 43% of tested specimens. This might be due to a higher organic content in this area.

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30

Snively, Eric. "Functional morphology of the tyrannosaurid arctometatarsus." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ64980.pdf.

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Stoffel, Michael H. "Functional morphology of the boar epididymis /." Bern : [s.n.], 2002. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.

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32

Bennett, Natasha. "Functional metal oxides : morphology and application." Thesis, University of Bristol, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.702459.

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Metal oxides have been widely studied, due to the many applications they are useful for. Their diverse properties, for example supercapacitance, piezoelectricity, semiconductivity and superconductivity have meant that research into metal oxides for application has been vast. Within this body of work, synthesis routes to manipulate the structure of several metal oxides were studied. These oxides were: Dy2Ti2O7, Gd2Ti2O7, CuBi2O4, CO3O4, NiO, α-Fe2O3 and several phases of strontium niobate. Utilising a biotemplated approach, morphology control and application was the key focus of the project.

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33

Jones, Catharine Rhian Gwyn. "The neuropsychology and functional anatomy of timing." Thesis, University College London (University of London), 2005. http://discovery.ucl.ac.uk/1444806/.

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This thesis explores the neural correlates of motor and perceptual timing. Motor timing involves the production of a timed movement (e.g. dancing), whereas perceptual timing requires a perceptual judgement (e.g. deciding which of two events lasted longer). A body of research has investigated this type of timing, concentrating on millisecond- and seconds-range intervals. Patients with Parkinson's disease (PD) and cerebellar pathology exhibit motor and perceptual timing deficits, which has led to the suggestion that both the basal ganglia and cerebellum are involved in this type of temporal processing. The research presented here uses a variety of techniques (functional imaging, transcranial magnetic stimulation (rTMS) and clinical studies on patients) to investigate the contribution of different neural structures to temporal processing. Using positron emission tomography (PET), the basal ganglia and cerebellum were both found to be active during millisecond- and seconds-range timing. However, only the basal ganglia were active when non-temporal aspects of the task were controlled for. At the cortical level, rTMS was used to show that the right dorsolateral prefrontal cortex was essential to the reproduction of seconds-range intervals, possibly due to a role in memory processes. In a further study, the motor and perceptual timing performance of patients with PD was modulated by dopaminergic medication, with medication improving performance. Patients with cerebellar disease displayed increased variability in timing tasks that included a significant motor component, but did not show impaired accuracy. A second PET study, comparing patients with PD and healthy controls, showed that the basal ganglia were active during motor timing for the control group. Compared to their medicated state, the patients showed decreased coupling between the basal ganglia and dorsolateral prefrontal cortex when 'off' medication. These studies support the notion that the basal ganglia, and not the cerebellum, play a fundamental role in motor and perceptual timing.

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34

Brough, C. "Functional anatomy of the ovaries of aphids." Thesis, University of East Anglia, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303714.

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35

Russell-Mergenthal, Helen. "Qualitative and quantitative morphology of lateral rectus motoneurons of the principal abducens nucleus." VCU Scholars Compass, 1985. https://scholarscompass.vcu.edu/etd/5602.

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Nine lateral rectus motoneurons of the principal abducens nucleus, intracellularly stained with HRP, were morphometrically analyzed by light microscopy using a new method for determining motoneuron size. Particular emphasis was placed on devising a method of estimating total dendrite size from the proximal dendritic diameter alone. The dendrites of these cells were divided into three types. One type, the microdendrites, had a consistent diameter of l micrometer, variable but short lengths, and added very little to the overall cell size. The majority of the dendrites on these cells (83) were standard in appearance but they could be separated into two further types. Six dendrites differed from the other 77 in that they were tapering processes which branched minimally, had both a rostrally and a caudally directed secondary dendrite and showed a larger ratio for the sum of the secondary dendrite diameters to the proximal dendrite diameter. The remaining 77 branched extensively and traveled either rostral or caudal in the brainstem. However, the most significant difference was quantitative. The tapering dendrites were approximately 2X the size of the prevalent branching dendrites based on proximal diameter measurements. Correlation coefficients of the relation between proximal diameter and surface area or volume of the entire dendrite increased when the correlations were separated into two types. Therefore, to insure the most accurate total size calculations, the regression lines used for estimating dendrite size were of the separate correlations. Total neuron size was calculated by adding the soma and dendrite surface areas. An intraneuronal comparison of size indicated that the size of the soma was not indicative of the size of the cell and it constituted between 2% to 7% of the total cell size. Comparison of the motoneuron size to the mechanical properties of their muscle units was inconclusive. However, a general tendency for small motoneurons to innervate muscle units of lower force output was observed. The smaller motoneurons were generally more dorsally located in the nucleus.

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36

Hensel, Marcus, and Marcus Hensel. "De Monstro: An Anatomy of Grendel." Thesis, University of Oregon, 2012. http://hdl.handle.net/1794/12552.

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Demon, allegory, exile, Scandinavian zombie—Grendel, the first of the monsters in the Old English Beowulf, has been called all of these. But lost in the arguments about what he means is the very basic question of what he is. This project aims to understand Grendel qua monster and investigate how we associate him with the monstrous. I identify for study a number of traits that distinguish him from the humans of the poem--all of which cluster around either morphological abnormality (claws, gigantism, shining eyes) or deviant behavior (anthropophagy, lack of food preparation, etiquette). These traits are specifically selected and work together to form a constellation of transgressions, an embodiment of the monstrous on which other arguments about his symbolic value rest.

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37

McElroy, Eric J. "The Functional Morphology of Lizard Locomotion: Integrating Biomechanics,Kinematics, Morphology, and Behavior." Ohio : Ohio University, 2008. http://www.ohiolink.edu/etd/view.cgi?ohiou1213879506.

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38

Marquardt, Mary Johanna. "Functional morphology of the anthropoid talocrural joint." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/5718.

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Thesis (M.A.)--University of Missouri-Columbia, 2008.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 13, 2009) Includes bibliographical references.

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Shimizu, Daisuke. "Functional Morphology of Molars of Folivorous Primates." 京都大学 (Kyoto University), 2001. http://hdl.handle.net/2433/86466.

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40

Gourvennec, Rémy. "Brachiopodes spiriferida du dévonien inferieur du massif armoricain : systématique, paléobiologie, évolution, biostratigraphie." Brest, 1987. http://www.theses.fr/1987BRES2033.

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Cet ouvrage est consacré aux spiriferides du dévonien inferieur du massif armoricain. L’étude systématique comprend la description de 51 espèces dont 17 nouvelles et 6 laissées en nomenclature ouverte; elle est complétée par une étude biométrique. Le chapitre consacre à la biologie traite de la morphologie fonctionnelle, de la croissance de la coquille, de paléoécologie et de l'étude des microsculptures et de leurs implications. On montre la prédominance des modalités évolutives de type anagénétique. L’étude de plusieurs coupes de référence permet d'établir la succession des espèces et de proposer des corrélations entre les différents domaines du massif armoricain et ceux de la péninsule ibérique.

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41

Chesselet, Pascale Claude Marcelle Henriette. "Systematic implications of leaf anatomy and palynology in the Disinae and Coryciinae (Orchidaceae)." Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/18698.

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Pollen morphology of 8 species (TEM), 86 species (SEM), and leaf anatomy of 62 species (LM), were surveyed in the Oisinae, Coryclinae and, as outgroup taxa, the Orchideae and Satyriinae. Characters extracted from observations made of leaf anatomy and pollen were analysed using cladistic methods, and assessed in relation to the present phylogeny of the group. Leaf anatomy data gave little phylogenetic information. Sclerification associated with vascular bundles was systematically useful. Pollen data served to resolve taxa at the subtribal level. Both data sets provided evidence of relationship for taxonomically problematic taxa. The Coryciinae are palynologically defined by a suite of synapomorphies, including a secondarily tectate exine structure, fasciculate massulae, and elongated tetrads with linear microspore configuration. Bibliography: pages 107-123.

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42

Miller, Jeri L. "Ultrasonic tissue characterization of the tongue : spectral features of tissue morphology." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0022/NQ50222.pdf.

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43

Rouse, Garrie Davis. "Comparative analysis of ovary development in selected members of the subtribe Abutilinae (Malvaceae)." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/101464.

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The gynoecia of all three species considered in this study originate not as individual carpel primordia but rather as a continuous ring. Processes of continued radial expansion and differential zonal growth give rise to the mature body of the gynoecium with no observable fusion taking place. Later manifestations of distinctness and separation of carpels represent secondarily acquired traits. Consequently, the mature gynoecia of the Malvaceae cannot be reliably used to infer early developmental events. The physical environment in which carpels originate is proposed to play a role in determining carpel number. Carpel size at inception does not vary considerably among the different species surveyed here. Ring size, however, does and this presumably dictates carpel number by the upward limit of what its circumference can ultimately accommodate. The uniovulate condition appears to be derived from the pluriovulate one through several interrelated developmental events. On the basis of acropetal initiation of ovules in Abutilon species and the precocious development of style primordia in Malacothamnus fasciculatus, a mechanism for the origin of the uniovulate carpel is proposed. Here, early style growth may limit zonal growth of the gynoecial base so that the acropetal series of ovule initiations is disrupted, leaving only a single basal one. The study of gynoecial development in this group has been hindered by certain problems of interpretation (e.g., Duchartre, 1845; Klotz, 1975; present account). These include difficulties in conceptualization of developmental processes and their reconciliation with preconceived views of the evolutionary origin of gynoecia. Consideration of relative size among successive stages is crucial, since the affect of radial growth is otherwise easily overlooked. Despite the differences of their mature gynoecia, the three species studied were determined to be strikingly similar in development, thereby supporting the close affinities attributed to them. In the final analysis, however, conclusive statements regarding the systematic implications of the ontogenetic patterns observed would be premature. Too few taxa have been studied and those that have should be reassessed in light of the developmental phenomena presented here.
M.S.

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44

Samuels, Joshua Xavier. "Paleoecology and functional morphology of beavers (family castoridae)." Diss., Restricted to subscribing institutions, 2007. http://proquest.umi.com/pqdweb?did=1495959451&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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45

Powell, J. E. "Metric versus non-metric skeletal traits : which is the more reliable indicator of genetic distance?" Thesis, University of Bristol, 1989. http://hdl.handle.net/1983/e44b5162-0f9d-4f0a-afdf-2eac49563e4b.

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46

Vedin, Viktoria. "Molecular and functional anatomy of the mouse olfactory epithelium." Doctoral thesis, Umeå : Umeå universitet, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-868.

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47

Biseswar, Ramlall. "The taxonomy and functional anatomy of Southern African Echiurans." Doctoral thesis, University of Cape Town, 1986. http://hdl.handle.net/11427/22476.

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The southern African echiuran fauna currently comprises two families, four genera and eighteen species. The taxonomic positions of three other species, one of Ochetostoma and two of Thalassema, remain to be resolved. Of the recorded species, three are new to science and a further five are new records for the southern African region. This survey reveals that there are ten species of Ochetostoma, four of Thalassema and three of Anelassorhynchus. The family Echiuridae contains a single genus, Echiurus and in southern Africa, E. antarcticus is the only species recorded to date. Full descriptions of the new species and those formerly inadequately described are given. The diagnoses of some others are modified and, where necessary, additional notes added. Keys for the identification of families, genera and species are provided and the taxonomic characters are evaluated and discussed. The zoogeographic distribution of the southern African species is mapped and an attempt has been made to analyse the recorded species on the basis of faunistic provinces. The phylogenetic position of the Echiura in the system of the animal kingdom is discussed. The lack of any form of segmentation of the mesodermal bands during embryonic developnent seems to justify their status as a separate phylum. The biomechanics of burrowing, locomotion and trunk irrigatory movements of Ochetostoma caudex are described and compared with the activities of some other animals with unsegmented coelomic cavities. Pressure changes within the coelom have been measured with the use of electronic recording techniques and the results interpreted in relation to direct visual observation. The anatomy of the reproductive system and the process of gametogenesis in O. caudex have been investigated with light and electron microscopes. Some observations on aspects of breeding behaviour and spawning are also included.

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48

Brazeau, Martin D. "Endocranial Morphology and Phylogeny of Palaeozoic Gnathostomes (Jawed Vertebrates)." Doctoral thesis, Uppsala universitet, Evolutionär organismbiologi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9360.

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Gnathostomes, or jawed vertebrates, make up the overwhelming majority of modern vertebrate diversity. Among living vertebrates, they comprise the chondrichthyans (“cartilaginous fishes” such as sharks, skates, rays, chimaeras) and the osteichthyans (“bony fishes” or bony vertebrates, inclusive of tetrapods). Gnathostomes appear to have originated in the early Palaeozoic Era, but their early fossil record is fairly scant. The best fossils appear first in the Late Silurian and Devonian periods. Much of gnathostome diversity owes to unique adaptations in the internal skeleton of their head (the endocranium). The endocranium is composed of the braincase, jaws, hyoid arch, and branchial arches, which sometimes fossilise when they are composed of bone or calcified cartilage. The purpose of this thesis is to describe and compare the fossilised cranial endoskeletons of a variety of different Palaeozoic gnathostomes. The objective is to test current conceptions of gnathostome interrelationships (i.e. phylogeny) and infer aspects of key morphological transformations that took place during the evolution of Palaeozoic members of this group. Two key areas are examined: the morphology and interrelationships of Palaeozoic gnathostomes and the morphology of the visceral arches in sarcopterygian fishes. New data on the visceral arches are described from the stem tetrapods Panderichthys and rhizodontids. These provide insight into the sequence of character acquisition leading to the tetrapod middle ear. Panderichthys shows key features of the tetrapod middle ear chamber were established prior to the origin fo digited limbs. New morphological data are described from the “acanthodian” fish Ptomacanthus. Ptomacanthus provides only the second example of a well-preserved braincase from any member of this group. It shows dramatic differences from that of its counterpart, Acanthodes, providing new evidence for acanthodian paraphyly. New interpretations of basal gnathostome and osteichthyan phylogeny are presented, challenging or enriching existing views of these problems.

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Sartori, André Fernando. "Comparative morphology and phylogeny of anomalodesmatan bivalves." Thesis, University of Cambridge, 2010. https://www.repository.cam.ac.uk/handle/1810/273157.

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Anomalodesmatans comprise a large, ancient and ecologically diverse group of marine bivalves, but are nonetheless inconspicuous in most extant shallow water communities. For various reasons, which include their present scarcity and a bewildering array of disparate morphologies, representatives of the group have always proved difficult to interpret, and their systematics lagged behind those of most other major bivalve taxa. Most of this dissertation reports the results of a comparative investigation on the shell morphology and anatomy of extant anomalodesmatans, which formed the basis for a reassessment of hypotheses of primary homology established by previous investigators and identification of novel characters for phylogenetic inference. Due to the chief role played by the hinge ligament in authoritative discussions of anomalodesmatan evolution, this organ was chosen as the focus of a more detailed treatment. Discontinuous ontogeny of fibrous ligament is shown to characterise several members of the group, with the implication that, in contrast to the prevailing model,not all anomalodesmatan adult ligaments may be considered homologous. Likewise, a system of multicellular glands concerned with sediment agglutination was studied with particular emphasis because it is both exclusive to and widespread within Anomalodesmata. Evidence of preserved glandular secretion is recorded for the first time in fossil material and the glands themselves found in extant laternulids and pholadomyids, thus considerably expanding their known taxonomic distribution. Finally, this volume also documents the largest cladistic analysis of extant anomalodesmatans performed to date, including morphological data compiled from both original observations and literature accounts. Among traditionally recognised superfamilies, Pholadomyoidea, Clavagelloidea and Septibranchia were found monophyletic. Taxa commonly referred to Pandoroidea and Thracioidea were recovered as part of two new clades, which are also supported by recent molecular studies. Interpreted in the light of the fossil record, reconstructed phylogenetic relationships favour the iterative evolution of shallow infaunal and epifaunal anomalodesmatans from deep-burrowing ancestors over previously advanced patterns for the history of the clade, namely ventral migration of the ligament and irreversible radiations into a deep infaunal life habit.

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Spears, Iain. "Functional adaptations of hominoid molars : an engineering approach." Thesis, University of Liverpool, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241490.

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Dissertations / Theses on the topic 'Functional morphology and anatomy'

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