Browsing by Author "Bevitt, JJ"
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- ItemThe 1st ANSTO-AINSE Workshop on Nuclear Techniques for Cultural Heritage(Taylor & Francis Online, 2019-05-24) Salvemini, F; White, R; McIntyre, GJ; Bevitt, JJ; Cubbin, KNo abstract available.
- ItemComputed tomographic analysis of the cranium of the early Permian recumbirostran ‘microsaur’ Euryodus dalyae reveals new details of the braincase and mandible(Wiley, 2021-05-12) Gee, BM; Bevitt, JJ; Reisz, RRRecumbirostran ‘microsaurs’ are a clade of Palaeozoic tetrapods that possess numerous morphological adaptations for fossorial ecologies. Re‐study of many ‘microsaurs’ using tomographic methods has provided substantial new data on poorly known anatomy that informs their debated phylogenetic position. Recent studies have identified suites of features among recumbirostrans that place the group within crown Amniota, contrary to hypothesized positions on the amniote stem or the lissamphibian stem. Herein we describe the cranial anatomy of the early Permian gymnarthrid Euryodus dalyae through tomographic analysis of the holotype from South Grandfield, Oklahoma and new specimens from karst deposits near Richards Spur. The braincase of E. dalyae is composed of well‐ossified pleurosphenoids, orbitosphenoids that brace against the skull roof, and unpaired median ossifications. The otic capsules are well‐ossified, and the occiput is unconsolidated. Analysis of the mandibles, typically obscured in articulated specimens, reveals a second tooth row on the dentary, a feature previously unknown in ‘microsaurs’ that is reminiscent of the condition of the co‐occurring captorhinid Captorhinus aguti. The Richards Spur specimens share many of these features, including the second tooth row, but the neurocranium of the scanned specimen (OMNH 53519) differs from that of the holotype of E. dalyae (e.g. absence of unpaired median ossifications), and these specimens are referred to Euryodus sp. These data add to the growing neurocranial dataset of ‘microsaurs’, which is essential for iterative reevaluation of early tetrapod phylogeny. This discovery of multiple tooth rows in ‘microsaurs’ provides further support for the hypothesized close relationships between ‘microsaurs’ and reptiles. © 1999-2024 John Wiley & Sons, Inc
- ItemCultural heritage project at Australian Nuclear Science and Technology Organisation (ANSTO)(Springer Nature, 2022-01-25) Salvemini, F; White, R; Levchenko, VA; Smith, AM; Pastuovic, Z; Stopic, A; Luzin, V; Tobin, MJ; Puskar, L; Howard, DL; Davis, J; Avdeev, M; Gatenby, S; Kim, MJ; Grazzi, F; Sheedy, K; Olsen, SR; Raymond, CA; Lord, C; Richards, C; Bevitt, JJ; Popelka-Filcoff, RS; Lenehan, CE; Ives, S; Dredge, P; Yip, A; Brookhouse, MT; Austin, AGThe Australian Nuclear Science and Technology Organization (ANSTO) is the home of Australia’s most significant landmark and national infrastructure for research. ANSTO operates one of the world’s most modern nuclear research reactors, OPAL; a comprehensive suite of neutron beam instruments; the Australian Synchrotron; the Electron Microscope Facility; and the Center for Accelerator Science. Over the years, the suite of nuclear methods available across ANSTO’s campuses has been increasingly applied to study a wide range of heritage materials. Since 2015 the strategic research project on cultural heritage was initiated in order to promote access to ANSTO’s capabilities and expertise, unique in the region, by cultural institution and researchers. This chapter offers a compendium of ANSTO nuclear capabilities most frequently applied to cultural heritage research. A series of innovative, interdisciplinary, and multi-technique studies conducted in close collaboration with Australian museums, institutions, and universities is also showcased. It includes research on dating Aboriginal Australian rock art and fingerprinting the sources of ochre pigments; rediscovering the technological knowledge in the making of early coinage and ancient weapons; virtually unwrapping the content of votive mummies from ancient Egypt; and investigating and restoring the original layer of a painting that can be explored by the museum audience in a novel type of exhibition based on an immersive, interactive, and virtual environment. © 2022 Springer Nature Switzerland AG
- ItemAn earliest Triassic age for Tasmaniolimulus and comments on synchrotron tomography of Gondwanan horseshoe crabs(PeerJ, 2022-04-22) Bicknell, RDC; Smith, PM; Brougham, T; Bevitt, JJConstraining the timing of morphological innovations within xiphosurid evolution is central for understanding when and how such a long-lived group exploited vacant ecological niches over the majority of the Phanerozoic. To expand the knowledge on the evolution of select xiphosurid forms, we reconsider the four Australian taxa:Austrolimulus fletcheri, Dubbolimulus peetae, Tasmaniolimulus patersoni, andVictalimulus mcqueeni. In revisiting these taxa, we determine that, contrary to previous suggestion,T. patersoniarose after the Permian and the origin of over-developed genal spine structures within Austrolimulidae is exclusive to the Triassic. To increase the availability of morphological data pertaining to these unique forms, we also examined the holotypes of the four xiphosurids using synchrotron radiation X-ray tomography (SRXT). Such non-destructive,in situimaging of palaeontological specimens can aid in the identification of novel morphological data by obviating the need for potentially extensive preparation of fossils from the surrounding rock matrix. This is particularly important for rare and/or delicate holotypes. Here, SRXT was used to emphasizeA. fletcheriandT. patersonicardiac lobe morphologies and illustrate aspects of theV. mcqueenithoracetronic doublure, appendage impressions, and moveable spine notches. Unfortunately, the strongly compactedD. peetaeprecluded the identification of any internal structures, but appendage impressions were observed. The application of computational fluid dynamics to high-resolution 3D reconstructions are proposed to understand the hydrodynamic properties of divergent genal spine morphologies of austrolimulid xiphosurids. 10.7717/peerj.13326 © 2022 Bicknell et al. Distributed under Creative Commons CC-BY 4.0
- ItemEndocasts of the basal sauropsid Captorhinus reveal unexpected neurological diversity in early reptiles(Wiley, 2022-10-14) Bazzana, KD; Evans, DC; Bevitt, JJ; Reisz, RRCaptorhinids are a group of Paleozoic amniotes that represents one of the earliest‐diverging clades of eureptiles. Although captorhinids are one of the best‐known and most well‐studied clades of early amniotes, their palaeoneuroanatomy has gone largely unexamined. We utilized neutron computed tomography to study the virtual cranial and otic endocasts of two captorhinid specimens. The neurosensory anatomy of captorhinids shows a mixture of traits considered plesiomorphic for sauropsids (no expansions of the cerebrum or olfactory bulbs, low degree of encephalization, low ossification of the otic capsule) and those considered more derived, including moderate cephalic and pontine flexures and a dorsoventrally tall bony labyrinth. The inner ear clearly preserves the elliptical, sub‐orthogonal canals and the short, rounded vestibule, along with an unusually enlarged lateral canal and a unique curvature of the posterior canal. The reconstructed neurosensory anatomy indicates that captorhinids were sensitive to slightly higher frequencies than many of their contemporaries, likely reflecting differences in body size across taxa, while the morphology of the maxillary canal suggests a simple, tubular condition as the plesiomorphic state for Sauropsida and contributes to the ongoing discussions regarding the phylogenetic placement of varanopids. This study represents the first detailed tomographic study of the brain and inner ear of any basal eureptile. The new data described here reveal that the neuroanatomy of early sauropsids is far more complex and diverse than previously anticipated, and provide impetus for further exploration of the palaeoneuroanatomy of early amniotes. © 2024 American Association for Anatomy.
- ItemEnigmatic amphibians in mid-Cretaceous amber were chameleon-like ballistic feeders(American Association for the Advancement of Science (AAAS), 2020-11-06) Daza, JD; Stanley, EL; Bolet, A; Bauer, AM; Arias, JS; Čerňanský, A; Bevitt, JJ; Wagner, P; Evans, SEExtant amphibians are represented by three fairly simple morphologies: the mostly hopping frogs and toads, the low-crawling salamanders, and the limbless caecilians. Until the early Pleistocene—and for more than 165 million years—there was another group, the albanerpetontids. We know little about this group because amphibian fossils are poorly preserved, and previous specimens from this group are both rare and mostly badly damaged. Daza et al. describe a set of fossils preserved in amber showing that this group was unusual both in their habitat use (they may been climbers) and their feeding mode, which appears to have been convergent with the ballistic feeding now seen in chameleons (see the Perspective by Wake).
- ItemExceptional preservation of organs in Devonian placoderms from the Gogo lagerstätte(American Association for the Advancement of Science, 2022-09-16) Trinajstic, K; Long, JA; Sanchez, S; Boisvert, CA; Snitting, D; Tafforeau, P; Dupret, V; Clement, AM; Currie, PD; Roelofs, B; Bevitt, JJ; Lee, MSY; Ahlberg, PEThe origin and early diversification of jawed vertebrates involved major changes to skeletal and soft anatomy. Skeletal transformations can be examined directly by studying fossil stem gnathostomes; however, preservation of soft anatomy is rare. We describe the only known example of a three-dimensionally mineralized heart, thick-walled stomach, and bilobed liver from arthrodire placoderms, stem gnathostomes from the Late Devonian Gogo Formation in Western Australia. The application of synchrotron and neutron microtomography to this material shows evidence of a flat S-shaped heart, which is well separated from the liver and other abdominal organs, and the absence of lungs. Arthrodires thus show the earliest phylogenetic evidence for repositioning of the gnathostome heart associated with the evolution of the complex neck region in jawed vertebrates. © 2022 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science.
- ItemFirst elaphrosaurine theropod dinosaur (Ceratosauria: Noasauridae) from Australia — a cervical vertebra from the early Cretaceous of Victoria(Elsevier, 2020-08) Poropat, SF; Pentland, AH; Duncan, RJ; Bevitt, JJ; Vickers-Rich, P; Rich, THElaphrosaurinae is an enigmatic clade of gracile ceratosaurian theropod dinosaurs known from the Late Jurassic of Africa (Elaphrosaurus bambergi) and Asia (e.g., Limusaurus inextricabilis), and the early Late Cretaceous of Argentina (Huinculsaurus montesi). Elaphrosaurinae is often placed within Noasauridae as the sister taxon to Noasaurinae, a clade of small-bodied theropods that lived in South America, Africa, Madagascar and India throughout much of the Cretaceous. Herein, we report the first evidence of Elaphrosaurinae from Australia: a nearly complete middle cervical vertebra from the upper Lower Cretaceous (lower Albian) Eumeralla Formation of Cape Otway, Victoria, Australia. The fact that this site would have been situated at ~76°S towards the end of the Early Cretaceous (~110–107 Ma) implies that elaphrosaurines were capable of tolerating near-polar palaeoenvironments, whereas its age indicates that elaphrosaurines persisted in Australia until at least the late Early Cretaceous. The new Australian elaphrosaurine, in tandem with the recently described Huinculsaurus montesi from the Cenomanian–Turonian of Argentina, implies that the spatiotemporal distribution of Elaphrosaurinae has heretofore been greatly underestimated. Historic confusion of elaphrosaurines with coelurosaurs, especially ornithomimosaurs, coupled with our generally poor understanding of noasaurid evolution, might explain the apparent dearth of fossils of this theropod clade worldwide. © 2020 International Association for Gondwana Research. Published by Elsevier B.V.
- ItemFossil barnacles from the Antarctic Peninsula: refining ways of exploring the nature of rare and/or delicate specimens employing X-ray Computer Tomography (CT)(Cambridge University Press, 2020-06-03) Stilwell, JD; Buckeridge, JSJS; Bevitt, JJ; Zahra, DAssessment of unique and potentially significant fossils may be considerably compromised by surrounding matrix. This paper assesses a fossil barnacle group from the mid to late Eocene of Seymour Island, off the Antarctic Peninsula, that potentially has very significant phylogenetic importance. It discusses why the specimen could be significant, and describes and applies as a proof of concept an advanced imaging technique, using X-ray Computed Tomography (CT), that was effectively employed to confirm systematic taxonomy with virtual 3-D sections through the specimen. In this case, the Antarctic barnacle's complex internal plate morphologies were resolved by advanced 3-D imaging, such that a taxonomic attribution could be made to either the Archaeobalanidae or Austrobalanidae, excluding the initial assessment of Coronulidae, which would have otherwise been allusive. © 2020, The Paleontological Society.
- ItemGuest adsorption in the nanoporous metal–organic framework Cu3(1,3,5-benzenetricarboxylate)2: combined in situ x-ray diffraction and vapor sorption(American Chemical Society, 2014-07-23) Peterson, VK; Southon, PD; Halder, GJ; Price, DJ; Bevitt, JJ; Kepert, CJThe structure of the nanoporous metal–organic framework Cu3(BTC)2 (BTC = 1,3,5-benzenetricarboxylate) with a variety of molecular guests was studied in situ using single crystal X-ray diffraction. By collecting crystal structure data for a series of guests within the same host crystal, insights into the molecular interactions underpinning guest adsorption processes have been gained. Adsorption behaviors are influenced strongly by both enthalpic and entropic thermodynamic, as well as interpore steric (size-exclusion) effects, and we note correlations between guest attributes and these effects. Vapor adsorption measurements revealed a guest uptake capacity inversely proportional to guest size. Correspondingly, structural results show that guests reside in the smallest pores accessible to them. Interpore steric effects for larger guests cause these to be excluded from the smallest pores, and this corresponds to lower total uptake. Both hydrophilic and lipophilic small guests adsorb favorably into the 5 Å diameter smallest pore of the material, with the number of guests in these pores dependent on guest size and their location, in turn dependent upon both guest–guest interactions and competition between hydrogen-bonding interactions at the apertures of the smallest pore and lipophilic interactions at the center of the smallest pore. Hydrophilic guests with lone electron pairs interact preferentially with the coordinatively unsaturated Cu sites of the desolvated framework, with the number of these depending on steric interactions between neighboring bound guests and guest flexibility. Guest coordination at the Cu sites has a significant effect on the framework structure, increasing the Cu···Cu distance in the dinuclear unit, with the Cu3(BTC)2 unit cell being smaller when guests that do not coordinate with the Cu are present, and in the case of cyclohexane, smaller than for the desolvated framework. Overall, our comprehensive structural study reconciles Cu3(BTC)2 adsorption properties with the underlying guest–host and guest–guest interactions that gives rise to these. © 2014, American Chemical Society.
- ItemHow to take a perfect image with DINGO(Australian Nuclear Science and Technology Organisation, 2021-11-24) Grigorova, V; Clark, SM; Bevitt, JJNeutron tomography is a powerful non-destructive technique used to study the internal structure of opaque objects. Neutron images are obtained by exposing an object to a uniform neutron beam. The transmitted neutrons interact with a phosphor which converts from neutrons to visible light, which is then demagnified on to a CCD camera. The modulation transfer function (MTF) is routinely used to determine the sharpness of an image, i.e. the ability of the imaging system to transfer information from an object to an image. The spatial frequency (SF) is the rate of transition between light and dark features in the image. For a perfect system where all of the frequency information is passed from object to image equally, the MTF of the will be 1 or 100% for all spatial frequencies and all features and contrast in the object will be transferred to the image. We performed a series of measurements to optimise the time necessary to obtain high-resolution radiographs with the DINGO instrument. We determined the MTF over a range of experimental conditions to understand the various contributions of DINGO’s imaging system variables to radiograph resolution. The system components varied in this study are the two beam modes, different scintillator screens, and pixel resolution of different cameras and lenses. We also compared the different exposure times of the object to the neutron beam to try to understand the minimum exposure time that will generate good resolution radiographs. Details of the use of this method for determining the quality of a neutron tomographic imaging system will be presented and the MTF data will be used to determine the optimal operating arrangement. © 2021 The Authors
- ItemMigration and formation of an iron rich layer during acidic corrosion of concrete with no steel reinforcement(Elsevier, 2021-11-22) Taheri, S; Giri, P; Ams, M; Bevitt, JJ; Bustamante, H; Madadi, M; Kuen, T; Gonzalez, J; Vorreiter, L; Withford, M; Clark, SMThe present study aimed to study the formation, enrichment, and relocation of iron-rich regions in the corroded area of concrete blocks, made without rebar, subjected to severely corrosive highly acidic conditions. In this work, three different concrete mix designs (a proprietary ready-mixed concrete, and laboratory made mortar and concrete) were corroded under induced accelerated conditions in sulfuric acid solutions at pH 1 for a duration of one to six months, in the absence of reinforcement (i.e. rebar) or iron-oxidizing bacteria. A variety of physicochemical and mechanical techniques were applied to monitor and assess the corrosion progress, and physical and chemical changes in the corroded samples. Results indicated a pronounced presence of iron rich layer (iron oxide/hydroxide) at the border of the corrosion front and the transition zone in all mix designs in the form of a ring. While existing papers in the literature describe the iron coming from the rebar, the only source of mobile iron in this experiment was from the iron oxide (Fe2O3) already in the cement. This zone (in a form of a ring) had an average iron content of 2.0 wt% and moved away from the surface to the center of the samples submerged in a sulfuric acid bath with the increase of immersion time, and it was accompanied by hairline cracks. The movement of this zone was in the same direction as sulfate (from acidic media) ingress and the opposite direction of calcium ion leaching, (Ca leaching). The rate of corrosion, the hardness and the compressive strength of concrete are mostly affected by the concrete mix design, the iron-ring enrichment and relocation had no significant impact on them. Detection of the iron-rich zone is an indication of the depth of corrosion at advanced stages in concrete products. © 2021 Elsevier Ltd
- ItemA Monte Carlo model of the Dingo thermal neutron imaging beamline(Springer Nature, 2023-12-01) Jakubowski, K; Charcon, A; Tran, LT; Stopic, A; Garbe, U; Bevitt, JJ; Olsen, SR; Franklin, DR; Rosenfeld, AB; Guatelli, S; Safavi-Naeini, MIn this study, we present a validated Geant4 Monte Carlo simulation model of the Dingo thermal neutron imaging beamline at the Australian Centre for Neutron Scattering. The model, constructed using CAD drawings of the entire beam transport path and shielding structures, is designed to precisely predict the in-beam neutron field at the position at the sample irradiation stage. The model’s performance was assessed by comparing simulation results to various experimental measurements, including planar thermal neutron distribution obtained in-beam using gold foil activation and BC-coated microdosimeters and the out-of-beam neutron spectra measured with Bonner spheres. The simulation results demonstrated that the predicted neutron fluence at the field’s centre is within 8.1% and 2.1% of the gold foil and BC-coated microdosimeter measurements, respectively. The logarithms of the ratios of average simulated to experimental fluences in the thermal (E 0.414 eV), epithermal (0.414 eV < E 11.7 keV) and fast (E 11.7 keV) spectral regions were approximately − 0.03 to + 0.1, − 0.2 to + 0.15, and − 0.4 to + 0.2, respectively. Furthermore, the predicted thermal, epithermal and fast neutron components in-beam at the sample stage position constituted approximately 18%, 64% and 18% of the total neutron fluence. © The Authors - Open Access Open Access This article is licensed under a Creative Commons Attribution 4.0 International.
- ItemMultiple tooth-rowed Parareptile from the early Permian of Oklahoma(Frontiers, 2021-08-25) Rowe, DCT; Scott, DM; Bevitt, JJ; Reisz, RRThe Dolese Limestone Quarry near Richards Spur, Oklahoma includes an elaborate system of caves which have been infilled with early Permian fossil rich sediments. In operation for more than a century, the quarry yielded vast numbers of disarticulated skeletal elements of the most diverse assemblage of fully terrestrial tetrapods from the Paleozoic. Excavations carried out in this century are distinct in producing large numbers of articulated and semiarticulated skeletons, including numerous new taxa. Dolese is therefore unique among early Permian localities in being home to a diverse assemblage of small parareptiles, including two species ofDelorhynchus. Here we describe a new species of acleistorhinid, characterized by the presence of multiple tooth rows on the dentary, that can be identified with confidence as a third new species ofDelorhynchus. The multiple tooth rowed condition is deemed not to be a pathological condition, and appears to have formed in the same manner as in the captorhinid eureptileCaptorhinus agutithrough uneven growth of the tooth-bearing element. © 2021 Rowe, Scott, Bevitt and Reisz. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).
- ItemNeurosensory anatomy and function in Seymouria(Wiley, 2023-03-08) Bazzana‐Adams, KD; Evans, DC; Bevitt, JJ; Reisz, RRSeymouria is among the best‐known stem amniotes and holds an important phylogenetic position for discussions of amniote evolution. Previous work has focused primarily on the osteology of Seymouria, with recent interest turning to the application of computed tomography (CT) to study the internal features. We utilized neutron CT to reconstruct the first virtual cranial endocast and the first complete otic endocasts of Seymouria, revealing previously unrecognized details of its palaeoneuroanatomy. The brain and inner ear of Seymouria are largely plesiomorphic relative to later‐diverging crown amniotes, showing no indication of increased encephalization or braincase ossification. Our results also clarify the plesiomorphic condition for carotid artery morphology in amniotes, with Seymouria showing a similar condition to basal members of both the synapsid and sauropsid lineages. The reconstructed neuroanatomy also indicates that Seymouria did not possess any particular neuroanatomical specializations, despite the probable presence of an impedance matching hearing system. © 2023 The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium,provided the original work is properly cited.© 2023 The Authors.
- ItemNeurosensory anatomy of Varanopidae and its implications for early synapsid evolution(Wiley, 2021-11-14) Bazzana, KD; Evans, DC; Bevitt, JJ; Reisz, RRVaranopids are a group of Palaeozoic terrestrial amniotes which represent one of the earliest‐diverging groups of synapsids, but their palaeoneurology has gone largely unstudied and recent analyses have challenged their traditional placement within synapsids. We utilized computed tomography (CT) to study the virtual cranial and otic endocasts of six varanopids, including representative taxa of both mycterosaurines and varanodontines. Our results show that the varanopid brain is largely plesiomorphic, being tubular in shape and showing no expansion of the cerebrum or olfactory bulbs, but is distinct in showing highly expanded floccular fossae. The housing of the varanopid bony labyrinth is also distinct, in that the labyrinth is bounded almost entirely by the supraoccipital‐opisthotic complex, with the prootic only bordering the ventral portion of the vestibule. The bony labyrinth is surprisingly well‐ossified, clearly preserving the elliptical, sub‐orthogonal canals, prominent ampullae, and the short, undifferentiated vestibule; this high degree of ossification is similar to that seen in therapsid synapsids and supports the traditional placement of varanopids within Synapsida. The enlarged anterior canal, together with the elliptical, orthogonal canals and enlarged floccular fossa, lend support for the fast head movements indicated by the inferred predatory feeding mode of varanopids. Reconstructed neurosensory anatomy indicates that varanopids may have a much lower‐frequency hearing range compared to more derived synapsids, suggesting that, despite gaining some active predatory features, varanopids retain plesiomorphic hearing capabilities. As a whole, our data reveal that the neuroanatomy of pelycosaur‐grade synapsids is far more complex than previously anticipated. © 1999-2024 John Wiley & Sons, Inc or related companies.
- ItemNeutron imaging: benefits and case studies in palaeontology and cutlural heritage(Australian Institute of Nuclear Science and Engineering (AINSE), 2020-11-11) Bevitt, JJ; Gabre, U; Salvemini, F; Raymond, CConventional and synchrotron-based X-ray computed tomography (XCT) have been utilised for many years as critical tools in uncovering 3-D internal and surface renderings of scientifically important fossils, cultural artefacts and other specimens held in museum and university collections. DINGO, Australia’s thermal-neutron micro-computed tomography (nCT) instrument, is being used to obtain unpreceded renderings of extraordinary fossilised anatomical features not visible with conventional imaging techniques, and yielding new insights into ancient manufacturing methods of archaeological artefacts not attainable by other methods. NCT is a complementary tool to XCT, and it is important to recognise the benefits, and challenges with its application. Using a selection of case studies from our instrument user program, this presentation will illustrate how neutrons are revealing soft-tissue remains in Jurassic stem-mammals, being used to identify touch-ups and fraud in palaeontology, and providing new insights into Cretaceous polar ecosystems. Through the ANSTO supported Cultural Heritage project, neutron imaging is being used to reveal ancient weapons manufacturing practices, reveal hidden texts in a lead scroll and identify the recycling of mummified votive offerings in ancient Egypt. Improvements in imaging technology and methods at ANSTO is enabling us to achieve higher throughput of these precious objects, minimise neutron-induced activation of samples and to support an increasing number and diversity of student-led research projects.
- ItemNeutron micro-CT as a non-destructive tool for palaeontology(Australian Institute of Nuclear Science and Engineering, 2016-11-29) Bevitt, JJThe physical extraction of fossilised remains from rocks enables quantitative physiological investigation of bone-dimensions, volume, and porosity, however leads to the destruction of valuable contextual information and soft-tissue remains within the matrix. Conventional and synchrotron-based X-ray computed tomography (XCT) have been utilised for many years as critical tools in uncovering valuable 3-D internal and surface renderings of scientifically important fossils, however poor contrast and X-ray penetration often prevents thorough tomographic analysis. DINGO, Australia’s first and only neutron micro-computed tomography (nCT) instrument is located at the OPAL nuclear research reactor. It is being used to obtain unpreceded reconstructions of extraordinary fossilised anatomical features not visible with conventional imaging techniques. This presentation will outline the physical capabilities of DINGO, the limitations and results to-date in the field of palaeontology. Drawing upon specimens scanned from across Australia, Antarctica, New Zealand, China and Mongolia, this presentation will demonstrate the complementarity of nCT to classic XCT methods, and its limitations. Evidence of extraordinary soft-tissue fossilisation in Jurassic fauna will be shown, along with insights into ancient and modern-day animals, achieved through the use of neutron CT scanning.
- ItemNeutron micro-CT as a non-destructive tool for palaeontology in Australia(Australian Institute of Nuclear Science and Engineering (AINSE), 2018-11-18) Bevitt, JJThe physical extraction of fossilised remains from rocks enables quantitative physiological investi gation of bonedimensions,volume, and porosity, however leads to the destruction of valuable con textual information and soft-tissue remains within the matrix. Conventional and synchrotron-based X-ray computed tomography (XCT) have been utilised for many years as critical tools in uncovering valuable 3-D internal and surface renderings of scientifically important fossils, however poor contrast and X-ray penetration often prevents thorough tomographic analysis. DINGO, Australia’s first and only neutron micro-computed tomography (nCT) instrument, located at the OPAL nuclear research reactor, is being used to obtain unpreceded reconstructions of ex traordinary fossilised anatomical features not visible with conventional imaging techniques. This presentation will outline the physical capabilities of DINGO, the limitations and results to-date in the field of palaeontology. Drawing upon specimens scanned from across Australia, North America, New Zealand, and China, this presentation will demonstrate the complementarity of nCT to classic XCT methods for certain geological formations and fossil localities. nCT has yielded unpreceded contrast and detailed-reconstructions of fossilised soft tissue in a Juras sic cynodont. The stomach contents and digestive function of herbivourous and carnivorous di nosaurs, and a Cretaceous Australian crocodilian have been revealed, providing insights into an cient environments and food chains. In this way, a new species of Australian dinosaur has been discovered. © The Author.
- ItemNew ankylosaurian cranial remains from the lower cretaceous (upper albian) toolebuc formation of Queensland, Australia(Frontiers, 2022-03-28) Frauenfelder, TG; Bell, PR; Brougham, T; Bevitt, JJ; Bicknell, RDC; Kear, BP; Wroe, S; Campione, NEAustralian dinosaur research has undergone a renaissance in the last 10 years, with growing knowledge of mid-Cretaceous assemblages revealing an endemic high-paleolatitude Gondwanan fauna. One of its most conspicuous members is ankylosaurs, which are rare but nonetheless occur in most Australian dinosaur-bearing formations spanning the uppermost Barremian to lower Cenomanian. Here we describe a partial ankylosaur skull from the marine Toolebuc Formation exposed near Boulia in western Queensland, Australia. This skull represents the oldest ankylosaurian material from Queensland, predating the holotype of Kunbarrasaurus ieversi, which was found in the overlying Allaru Mudstone. The ankylosaur skull is encased in a limestone concretion with the maxillary tooth rows preserved only as impressions. Synchrotron radiation X-ray tomography was used to non-destructively image and reconstruct the specimen in 3D and facilitate virtual preparation of the separate cranial bones. The reconstruction of the skull revealed the vomer, palatines, sections of the ectopterygoids and maxillae, and multiple teeth. The palate has posteriorly positioned choanae that differs from the more anterior placement seen in most other ankylosaurians, but which is shared with K. ieversi, Akainacephalus johnsoni, Cedarpelta bilbeyhallorum, Gobisaurus domoculus, and Panoplosaurus mirus. Phylogenetic analyses place the new cranial material within the recently named basal ankylosaurian clade Parankylosauria together with K. ieversi. This result, together with the anatomical similarities to the holotype of K. ieversi, permits its referral to cf. Kunbarrasaurus sp. This specimen elucidates the palatal anatomy of Australian ankylosaurs and highlights one of the most ubiquitous components of Australian mid-Cretaceous dinosaur faunas. © 2022 Frauenfelder, Bell, Brougham, Bevitt, Bicknell, Kear, Wroe and Campione. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).