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Postcranial evolution in marsupials: comparative analyses of autopodial diversity and postcranial skeletal ontogenyWeisbecker, Vera, Biological, Earth & Environmental Sciences, Faculty of Science, UNSW January 2008 (has links)
Marsupial evolution and morphological diversity is traditionally viewed against the background of marsupial life history, central to which are the highly altricial neonates that actively move towards the teat. It has been suggested that this mode of birth leads to a constraint on the marsupial postcranial diversity. However, apart from phylogenetic investigations, few empirical studies have assessed diversity, patterns of adaptation, or ontogeny of the marsupial postcranium. This thesis contributes to the debate by providing diverse, large-scale empirical data on selected issues of marsupial postcranial evolution, using multidisciplinary approaches with focus on quantitative analysis. Chapter 1 provides an overview on previous research on this topic. Chapter 2 assesses the phylogenetic and functional-anatomical implications of marsupial carpal diversity. Chapter 3 is a phylogenetically informed morphometric analysis of diprotodontian manual digits, demonstrating locomotor adaptations similar to those in placentals and allowing the development of a new locomotor predictor ratio. Chapter 4 shows that functional correlates of digit proportions in Diprotodontia also exist in the placental hystricomorph rodents, which resemble Diprotodontia in ecological diversity. Chapter 5 applies the results from Chapters 2-4 to the mostly extinct diprotodontian suborder Vombatiformes, revealing functionally related parallelism in the hand of vombatiforms and kangaroos and questioning previous concepts of locomotion in early vombatiforms. Chapter 6 focuses on the evolution of marsupial syndactyly using a multidisciplinary approach including morphometrics and ossification sequence analysis. The results suggest that syndactylous digits evolve as a functional unit; syndactyly may arise through alteration of developmental patterns as suggested by ossification sequence heterochrony. Chapter 7 is a combined analysis of ossification sequences in marsupial and placental postcrania. The results suggest that the special locomotor and developmental requirements on marsupial neonates may metabolically and mechanically impact postcranial ossification patterns, delaying hindlimb development and accelerating ossification of the anterior torso. Chapter 8 summarises the research presented in this thesis and suggests directions for future work on marsupial postcranial evolution, particularly with respect to integrating information on postcranial diversity with ontogenetic work on morphogen expression patterns.
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Postcranial Osteometric Assessment of Korean AncestryOkrutny, Elizabeth Carol 01 January 2012 (has links)
The determination of ancestry is an important part of an individual's identification when creating a biological profile. This thesis scrutinizes postcranial variation using over 65 osteometric sorting measurements in an attempt to identify those measurements that display the most significant differences among Koreans, Africans, and Europeans. Data was collected from four American skeletal collections and one South Korean skeletal collection for a total sample population of 306 individuals: 24 of Korean ancestry, 66 of African ancestry, and 216 of European ancestry. In an effort to minimize the number of measurements needed for ancestral assessment, stepwise discriminant analysis was performed for measurements of each skeletal region and region combinations. Initial findings highly misclassified Africans, so the results of this study were separated into two parts: Koreans from Africans/Europeans and Africans from Europeans. A majority of the functions developed in the first part of the analysis resulted in cross-validated classifications of 80% and greater for Koreans and 77% or greater for Africans/Europeans with the highest classifying function for both ancestral groups being composed of upper limb measurements. Most of the discriminant functions from the second part of the analysis correctly differentiated Africans with 70% or greater accuracy and Europeans with 72% or greater accuracy with the highest classifying function for both groups consisting of pelvis, lower limb, and foot measurements. These functions indicate that ancestry can be determined successfully from postcranial elements; that certain skeletal regions are better indicators of ancestry than others; and that osteological remains do not need to be complete to develop an informative biological profile.
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Postcranial anatomy of Tanius sinensis Wiman, 1929 (Dinosauria; Hadrosauroidea) / Postkraniala anatomin hos Tanius sinensis Wiman, 1929 (Dinosauria; Hadrosauroidea)Borinder, Niclas January 2015 (has links)
Tanius sinensis Wiman, 1929 was one of the first hadrosauroid or “duck-billed” taxa erected from China, indeed one of the very first non-avian dinosaur taxa to be erected based on material from the country. Since the original description by Wiman in 1929, the anatomy of T. sinensis has received relatively little attention in the literature since then. This is unfortunate given the importance of T. sinensis as a possible non-hadrosaurid hadrosauroid i.e. a member of Hadrosauroidea outside the family of Hadrosauridae, living in the Late Cretaceous, at a time when most non-hadrosaurid hadrosauroids had become replaced by the members of Hadrosauridae. To gain a better understanding of the anatomy of T. sinensis and its phylogenetic relationships, the postcranial anatomy of it is redescribed. T. sinensis is found to have a mosaic of basal traits like strongly opisthocoelous cervical vertebrae, the proximal end of scapula being dorsoventrally wider than the distal end, the positioning of the ventral apex of the supra-acetabular process of the ilium, posterodorsally to the ischial peduncle, the ratio between the proximodistal length of the metatarsal III and the mediolateral width of this element being greater than 4.5. Derived traits present in T. sinensis include curved dorsal surface of the scapula, arcuate fourth trochanter of the femur, cnemial crest of the tibia extending ventrally into the proximal half of the shaft, and the distal end of the fibula expanding into a club shape in lateral view. A potential autapomorphy is noted, being the caudal fusion of the medial and lateral condyles of the femur forming a completely enclosed “tunnel”. The body mass of the holotype of T. sinensis, is also estimated, and found to have been around 2950 kg. The phylogenetic analysis agrees with previous studies placing T. sinensis as a non-hadrosaurid hadrosauroid. Furthermore, in the phylogenetic analysis, T. sinensis is recovered as non-hadrosaurid hadrosauroid, forming a clade with Bactrosaurus johnsoni Gilmore, 1933, which shares the following unambiguous synapomorphies; the width of the orbital margin of the jugal being almost equally wide to that of the infratemporal margin of the bone; the ratio between the mediolateral width of the skull roof across the postorbitals and that across the quadrate cotyli of the paired squamosals being more than 1.20. / Den här uppsatsen handlar om Tanius sinensis Wiman, 1929 som levde under Kritaperioden i Shan-dongprovinsen i nordöstra Kina. Tanius sinensis hörde till gruppen ”Anknäbbsdinosaurier” som ut- vecklades under början av Kritaperioden för mellan 130-100 miljoner år sedan. I slutet av Kritaperi- oden för ungefär 84 miljoner år sedan så blev de ”primitiva” ”anknäbbsdinosaurierna” bortträngda av de mer ”avancerade” ”anknäbbsdinosaurierna”. Tanius sinensis är viktig på så vis att den kan ha varit en ”primitiv” ”anknäbbsdinosaurie” som överlevde vid en tidpunkt när de flesta andra ”primitiva” ”anknäbbsdinsoaurier” hade trängts undan. För att få en bättre bild av T. sinensis anatomiska känne- tecken och en bättre bild av dess släktskapsförhållanden, så ombeskrivs anatomin hos den del av skelettet som inte omfattar kraniet. En släktskapsanalys görs också baserat på de kännetecken som jag själv och tidigare forskare har observerat i skelettet. De anatomiska observationerna avslöjar en mosaik av ”primitiva” och mer ”avancerade” karaktärer, som tillsammans med släktskapsanalysenpekar på att T. sinensis var en sent överlevande ”primitiv” ”anknäbbsdinosaurie”.
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Morphological and functional analysis of the postcranial anatomy of two dicynodont morphotypes from the cynognathus assemblage zone of South Africa and their taxonomic implicationsRomala, Govender 26 February 2007 (has links)
Student Number : 9202936M -
PhD thesis -
School of Geoscience -
Faculty of Science / Kannemeyeria simocephalus is probably the best known Middle Triassic dicynodont from South Africa and has been the standard against which other Triassic dicynodonts are compared. In the past studies have concentrated on the cranial morphology of K. simocephalus and how this affected Triassic dicynodont taxonomy and phylogeny. There has been little work on the postcranial anatomy of K. simocephalus, which remains poorly understood. This current study undertook a detailed descriptive analysis of the postcranial anatomy of K. simocephalus that lead to the identification of diagnostic characters of the postcranial skeleton. During the course of the analysis of the postcranial anatomy of K. simocephalus it was noted that material previously assigned to this taxon was significantly different from that recognised as K. simocephalus. Unfortunately, this material consists only of postcranial material and it is therefore referred to as Morphotype B rather than a new species of Kannemeyeria or as a new taxon from the Cynognathus Assemblage Zone (subzone B). A phylogenetic analysis was performed which included K. simocephalus and Morphotype B, and used cranial and postcranial characters. The preliminary phylogenetic results show that there are possibly two taxa of medium to large dicynodonts in the Cynognathus Assemblage Zone (subzone B); one a kannemeyeriid and the second a stahleckeriid. It has also evident that more attention needs to be paid to the study of the postcranial anatomy of Triassic dicynodonts, especially those from Africa and Asia.
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The Postcranial Skeleton of Temnospondyls (Tetrapoda: Temnospondyli)Pawley, Kat, kat.pawley@rmit.edu.au January 2006 (has links)
Temnospondyls are large extinct fossil tetrapods; superficially resembling crocodiles in their general size, appearance and lifestyle. Temnospondyls are a group of early tetrapods, the oldest fossils are more than 340 million years old, and they existed for more than 200 million years. This doctoral thesis examined the postcranial skeleton of temnospondyls and its evolutionary history and diversification. Standard taxonomic techniques were used to distinguish between the types of variation observed in the postcranial skeleton and for phylogenetic analysis. The thesis consists of a series of published articles, three describing the postcranial skeletons of various temnospondyls, and three summary articles, all with extensive illustrations.
To provide data, the postcranial skeletons of three temnospondyl taxa were described. The articulated postcranial skeleton of a basal stereospondyl (rhinesuchid) is immature, and paedomorphism of the postcranial skeleton in stereospondyls is discussed. The robust appendicular skeleton of Eryops megacephalus is plesiomorphic, well-ossified, and terrestrially adapted. The paedomorphic postcranial skeleton of Trimerorhachis insignis is plesiomorphic, and secondarily aquatic, the description includes growth stages.
This study found that extensive morphogenetic variation is present in the postcranial skeleton of temnospondyls. Many phylogenetically significant characteristics develop with morphogenesis, they may be absent in early growth stages, and may never develop even in the largest growth stages of taxa with paedomorphic postcranial skeletons. Consequently, assessment of the presence or absence of a phylogenetically significant characteristic in any taxon may be dependant on the morphogenetic stage of the specimen examined. This finding has major implications for the phylogenetic analysis of temnospondyls and other early tetrapods.
An overview of phylogenetic variation in the postcranial skeleton is presented, including a large phylogenetic analysis of the Temnospondyli. The most primitive temnospondyls possess fully ossified postcranial skeletons, well adapted for terrestrial locomotion, but some of the derived clades of temnospondyls have paedomorphic postcranial skeletons and are exclusively aquatic.
For the first time, the postcranial skeleton of temnospondyls is comprehensively compared with that of other early tetrapods in the largest phylogenetic analysis to date, resulting in the unexpected discovery that temnospondyls are most closely related to the ancestors of amniotes. The Temnospondyli plus Neospondyli (Seymouriamorpha plus Cotylosauria plus Lepospondyli) forms a large new clade, the Terrapoda, defined by the presence of many derived synapomorphies. Some of the cranial synapomorphies of the Terrapoda are most likely related to improvements in hearing. The postcranial synapomorphies indicate that the Terrapoda are the first vertebrates to have evolved limbs that are well adapted for terrestrial locomotion. The Terrapoda are the first truly terrestrial vertebrates, their postcranial adaptations facilitated their colonisation of the land and consequent phylogenetic radiation during the early Carboniferous.
Both analyses incorporate characters from previous analyses and many new postcranial characters. The results of the phylogenetic analyses are statistically more parsimonious than previous analyses and have much lower levels of homoplasy. Comparative analyses indicate that the distinctive results are most likely due to the increased use of characters pertaining to temnospondyls, increased use of postcranial characters, and differentiation between sources of morphological variation to minimise morphogenetic and phenotypic variation and elucidate true phylogenetic signal.
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THE EVOLUTION OF HYLOBATID POSITIONAL BEHAVIOR AND POSTCRANIAL OSTEOLOGYNowak, Matthew Gerard 01 May 2024 (has links) (PDF)
A comparative understanding of the patterns and processes of hominoid evolution is critical for determining the evolutionary trajectories of our own species. Several traits, including the development of relatively large-body size, a torso-orthograde (or upright; TO) -Bauplan, and suspensory adaptations are often considered key adaptations within the Hominoidea. Unfortunately, comparisons of the neontological and paleontological records have resulted in divergent theories regarding the origin of these traits, with one extreme advocating their homologous origins and the other for rampant homoplasy. It is argued here that a key factor that has continued to limit our understanding of hominoid and human evolution is the underutilization of hylobatids within comparative studies. The Hylobatidae are an extremely successful radiation of moderate-sized primates from the superfamily Hominoidea. The extant hylobatid family currently comprises four genera and 20 species spanning 11 countries in East, South, and Southeast Asia, with three known extinct genera from China and potentially one from India. Hylobatids are the smallest of the extant apes yet size-variable and are among the most orthograde/suspensory. Nevertheless, their natural variation is often condensed into a single observation point in comparative studies. As such, the goal of this dissertation is to document the variation in positional behavior and postcranial osteology among hylobatids, utilizing an ecological morphological framework, and to integrate this detailed evaluation with previous neontological and paleontological studies. Several interrelated studies are presented within this dissertation, including a new comparative look at hylobatid postcranial osteology and several new studies of hylobatid positional behavior from the wild. These investigations shed light on the adaptive niche of hylobatids and provide insights into the evolutionary processes that shaped this uniquely successful hominoid family. Moreover, the new results presented here allow for a more critical understanding of hominoid evolution and facilitate the synchronization of the neontological and paleontological records. In doing so, this study provides support to the theory that hylobatids and hominids have developed their body size regimes, TO-Bauplan, suspensory morphological adaptions, and accompanying TO-positional behavioral repertoire independently.
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Ekologické faktory ovlivňující složení potravy kalouse ušatého Asio otus (Linnaeus, 1758) / Ecological Factors and their Impact on a Diet of the Long -eared Owl (Asio otus)Gaďůrková, Kateřina January 2013 (has links)
My thesis deals with ecology and diet of the Long - eared Owl (Asio otus). The study area a wintering place is situated near the town of Kladno. 1) The hypothesis that a high snow cover has an influence on the Long-eared Owl diet has been confirmed. 3) The thesis deals with the determination methods of small vertebrate species in Long - eared Owl's diet. The work deals with postcranial skelet as well. There was compilled the method of the sex determination in Common vole (Microtus arvalis). The sex determination was based on the morphological differences of the pelvic bones. The results (sex ratio) had been statistically tested and as such found significant. 2) There were also analyzed the skeletal remnants of the pelvic bones in the pellets. The study of the pelvic bones was carry out in order to find expected seasonal changes in the sex ratio in a dominant prey Common vole (Microtus arvalis). That hypothesis was not confirmed. Keywords: Long-eared owl (Asio otus), diet, postcranial skeleton, pelvic bones
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Anatomy, taxonomy, ontogeny and phylogeny of basal mosasaurians (Squamata, Mosasauria) and their implications to the evolution of Anguimorpha / Anatomia, taxonomia, ontogenia e filogenia de mosassaurianos basais (Squamata, Mosasauria) e suas implicações para a evolução de AnguimorphaAugusta, Bruno Gonçalves 01 February 2019 (has links)
Mosasauria is a clade of essentially Late Cretaceous marine reptiles. Although well known by several nicely preserved specimens, phylogenetic relationships of mosasaurians within Squamata are still a matter of intense debate. Most of the works discussing the relationships of mosasaurians in global contexts of squamates were based mainly on more derived taxa, including only few basal forms. Here the anatomy, phylogeny, ontogeny and taxonomy of the basalmost mosasaurian radiation, the commonly known \"dolichosaurs\", is reviewed, mostly on the light of new and exquisitely preserved coniasaur remains from Texas. New remains described here encompass dozens of specimens, including a new species represented by a gravid female and several embryos. A revision of the genus Coniasaurus suggest it as encompassing four species: C. crassidens, C. longicollis (former Dolichosaurus longicollis), C. gracilodens and the new taxon described here. Contrary to what is observed in more derived forms, the patterns of tooth attachment in coniasaurs are very similar to those of varanoids, suggesting similarities between tooth attachment and implantation in snakes and derived mosasaurs to be the result of homoplasies. The evolution of the dolichosaurian postcranial anatomy is assessed, finding new diagnostic characters for several distinct lineages. A phylogenetic analysis of Mosasauria in a global matrix of squamates, including the largest sample of basal forms ever tested, consistently found the group to be closely related to Varanoidea, rejecting the hypotheses of the group being closely related either to snakes or lying in a more basal position among squamates. Results gathered by this thesis are expected to greatly contribute to the knowledge of this astonishing group / Mosasauria é um clado formado essencialmente por répteis marinhos do Cretáceo Superior. Embora bem conhecido por diversos espécimes, as relações filogenéticas do grupo dentro de Squamata formam um tópico de intenso debate. A maior parte dos trabalhos discutindo o tema em análises globais de Squamata foram baseadas em táxons mais derivados, incluindo apenas poucas formas basais. Aqui, a anatomia, filogenia, ontogenia e taxonomia da irradiação mais basal do grupo, os \"dolicossauros\", foi revista, principalmente à luz de novos restos fósseis de coniassauros do Texas. Os novos fósseis descritos aqui englobam dezenas de espécimes, incluindo uma nova espécie representada por uma fêmea gravida e diversos embriões. Uma revisão do gênero Coniasaurus sugere que o mesmo engloba quatro espécies: C. crassidens, C. longicollis (antes Dolichosaurus longicollis), C. gracilodens e o novo táxon descrito aqui. Ao contrário do observado em formas mais derivadas, os padrões de fixação dentária nos coniassauros é muito similar àqueles dos varanóides, sugerindo que as similaridades observadas nestes padrões entre serpentes e mosassauros derivados resulta da ocorrência de homoplasias. A evolução do esqueleto pós-craniano dos dolicossauros foi avaliada, encontrando novos caracteres diagnósticos para diferentes linhagens. Uma análise filogenética de Mosasauria em uma matriz global de Squamata, incluindo a maior amostragem de formas basais já testada, consistentemente encontrou o grupo como proximamente relacionado ao clado Varanoidea, rejeitando hipóteses de proximidade com serpentes ou numa posição mais basal dentro de Squamata. Espera-se que os resultados provenientes desta tese contribuam consideravelmente para o conhecimento deste incrível grupo
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Les variations osseuses asymptomatiques du squelette postcranien : leur contribution à l'identification en anthropologie médico-légale / The asymptomatic osseous variation of postcranial skeleton : their contribution to the identification in forensic anthropologyVerna, Emeline 11 December 2014 (has links)
En anthropologie médico-légale la détermination du sexe, l'estimation de l'âge au décès et l'estimation de la stature sont des paramètres essentiels à la constitution du profil biologique d'un individu à partir de restes osseux. Toutefois uniquement à partir de ces trois paramètres les interprétations sont limitées, plusieurs individus peuvent partager un même profil. L'introduction et l'observation d'autres paramètres, comme les variations anatomiques, peuvent être un atout dans l'établissement du profil biologique le plus singulier et complet possible afin de ne correspondre qu'à un nombre très restreint d'individus voire à un seul individu. En plus des variations anatomiques, l'observation des marqueurs de posture et des anomalies congénitales asymptomatiques peut aussi se révéler être pertinente. Ils ont été regroupés sous le terme de Variations Osseuses Asymptomatiques (VOA). Cent-neuf VOA ont été recensées sur le squelette postcrânien et 82 ont été étudiées à partir de 1300 individus provenant de trois populations différentes : une population contemporaine (imagerie médicale), une population ostéologique de référence et une population ostéoarchéologique. Pour chacune des VOA, la fréquence a été obtenue à partir des trois échantillons puis une fréquence en fonction du sexe, de l'âge et de la latéralité a été calculée. Une iconographie claire de chaque VOA a été obtenue. L'intérêt final est de ne sélectionner que les VOA ayant une fréquence inférieure à 10 % et facilement observables afin d'aider à l'identification en complétant le profil biologique, et ceci à partir d'une méthode basée sur la comparaison de données ante et post-mortem. / In forensic anthropology, determination of sex, estimation of age at death and estimation of stature are essential parameters for constituting the biological profile of an individual from bone remains. However, using only three parameters limits interpretation, several individuals could share the same profile. The introduction and observation of others parameters, particularly anatomical variations, could help establish a more complete and specific biological profile to correspond to a restricted number of individuals or to a unique individual. In addition to anatomical variations, postural markers and congenital anomalies can be useful for identification purposes. These 3 elements are regrouped under the term Asymptomatic Osseous Variation (AOV). 109 AOVs were found on the postcranial skeleton and 82 were studied on 1300 individuals from three different populations: a contemporary population (medical imaging), an osteological collection of reference and an osteoarcheological population. Frequencies were obtained from the three samples for each AOV, and frequencies according to sex, age and laterality were calculated. A clear iconography of each AOV was obtained. This data enabled the classification of the AOVs according to 5groups of frequencies, ranging from very rare to very frequent. The AOVs were also classified according to their liaison with sex, age and laterality. The final goal is to select only AOVs with a frequency inferior to 10% (qualified as rare), that are easily observable, to be useful for establishing the biological profile and help identify the individual, using a method based on ante and post-mortem data comparison.
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Caractérisation multi-site de la distribution osseuse corticale et de l'organisation du réseau trabéculaire du squelette postcrânien de Paranthropus robustus : implications taxonomiques, fonctionnelles et paléobiologiques / Multi-site characterisation of cortical bone distribution and cancellous network organisation in the Paranthropus robustus postcranial skeleton : taxonomic, functional and paleobiological implicationsCazenave, Marine 15 October 2018 (has links)
Le taxon du Pléistocène inférieur Paranthropus robustus, dont l'holotype est le spécimen TM 1517, a été défini en 1938 par le paléontologue R. Broom suite à la découverte d'éléments crâniens et postcrâniens sur le site de Kromdraai, Gauteng, en Afrique du Sud. Depuis, d'autres sites sud-africains ont contribué à l'extension de son hypodigme et fourni la preuve de sa contemporanéité à l'échelle macro-régionale avec des représentants des taxons Australopithecus et Homo. L'identification des hominines étant principalement basée sur l'analyse de la variation morphologique des éléments cranio-dentaires, un enjeu majeur dans l'étude des assemblages fossiles des sites sud-africains concerne donc l'identification et l'attribution taxinomique de restes isolés et/ou fragmentaires du squelette axial et appendiculaire non associés à des éléments cranio-dentaires. Il en résulte que plusieurs aspects fonctionnels et paléobiologiques du squelette postcrânien de P. robustus restent à préciser. Au moyen de la microtomographie à rayons X, de l'imagerie virtuelle et d'analyses quantitatives en deux-trois dimensions, nous avons entrepris un projet de recherche visant à explorer, extraire et les patrons d'organisation endostructurale de spécimens fossiles communément, ou préliminairement, attribués à P. robustus. Sur une base comparative, nous visons à (i) identifier quelques caractéristiques osseuses endostructurales propres à ce taxon, qui pourraient fournir un cadre de référence pour l'attribution de spécimens fossiles isolés; (ii) déconstruire l'environnement biomécanique ayant façonné l'arrangement de l'os cortical et trabéculaire au niveau des articulations du coude, de la hanche et du genou; (iii) évaluer le degré de variation et, dans la mesure du possible, les différences liées au sexe et à l'âge. L'échantillon étudié comprend quatre huméri distaux (TM 1517g, SK 24600, SKX 10924, SKX 34805), cinq fémurs proximaux (SK 82, SK 97, SK 3121, SKW 19, SWT1/LB-2), une patella (SKX 1084), des éléments additionnels échantillonnant l'assemblage TM 1517 (l'ulna proximale TM 1517e, la phalange distale d'hallux TM 1517k) et deux ilia (TM 1605, SK 50) provenant des sites de Kromdraai et Swartkrans. [...] / The Early Pleistocene taxon Paranthropus robustus, represented by the holotype TM 1517, was established in 1938 by the paleontologist R. Broom following the discovery of craniodental and postcranial remains at the cave site of Kromdraai, in Gauteng, South Africa. Since, other Southern African sites have contributed to the extension of its hypodigm, providing evidence for its chronological overlap in the macro-region with representatives of the taxa Australopithecus and Homo. As species identification in the hominin fossil record is commonly based on the comparative assessment of craniodental anatomy and morphological variation, the rarity in the hominin-bearing South African cave assemblages of unambiguously associated craniodental and postcranial remains usually complicates the task of identifying isolated and fragmentary elements from the axial and the appendicular skeleton. Consequently, different functionally- and paleobiologically-related aspects of the P. robustus postcranial skeleton remain poorly known. By means of techniques of high resolution X-ray micro-tomography and virtual imaging coupled with two-three-dimensional quantitative analyses, in this research project we explored, extracted and assessed the patterns of endostructural organisation in some fossil specimens commonly, or tentatively, attributed to P. robustus. On comparative ground, we aim at (i) identifying some endostructural bony features characteristic of this taxon, if any, thus tentatively providing a reference framework for the attribution of isolated fossil specimens; (ii) deconstructing the biomechanical (loading) environment having shaped the cortical and cancellous bone arrangement at the elbow, the hip, and the knee joints; (iii) assessing variation and, whenever possible, sex- and age-related differences. The investigated sample consists of four distal humeri (TM 1517g, SK 24600, SKX 10924, SKX 34805), five proximal femora (SK 82, SK 97, SK 3121, SKW 19, SWT1/LB-2), a patella (SKX 1084), some additional elements from the assemblage labelled TM 1517 (the proximal ulna TM 1517e, the distal hallucial phalanx TM 1517k), and two ilia (TM 1605, SK 50) from the sites of Kromdraai and Swartkrans. [...]
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