Qhemegha Fossil vertebrate Synchrotron

This study aims to reveal the histology of new theropod material from the Elliot Formation using non-destructive propagation phase contrast X-ray micro-computed tomography at the European Synchrotron Radiation Facility. Because this material is the first known theropod material from the Triassic part of the Elliot Formation, it must first be examined using non-destructive methods. The outcome of this study will provide critical new information on the growth and physiology of apex predators of the Triassic. These are highly active research areas of palaeontological inquiry, and the results from this study should be publishable in high-impact journals. This project will form the basis for a South African PhD project (Mukwevho), and also the data expected from this study will prove to be of broad public interest with predicted generalised media releases.

Methodology (short):
The specimens will be subjected to propagation phase contrast X-ray micro-computed tomography at the European Synchrotron Radiation Facility in Grenoble, France. This is a non-destructive 3D imaging technique. Each specimen will be scanned at a single region of interest (ROI) suitable for virtual osteohistology, generally at the minimum mid-diaphyseal diameter (but in some cases this will be optimized given specimen preservation and geometry). Each specimen will be scanned at three resolutions (6, 2.5, and 0.7μm), to facilitate gross, fine, and micro bone anatomy. Specimens to be scanned will be individually mounted in acrylate tubes containing archival foam. The tube will be secured to the tomograph using masking tape and no non-archival material will contact the specimen. Exposure to x-rays will be minimized for each specimen and we envision scan times of less than 20 minutes per region of interest. Resulting scan data will be transferred to the ESI via couriered hard drives or via the ESRF’s GLOBUS ftp system. The data will be archived at the ESI, and uploaded to Morphosource with appropriate curatorial permissions requirements during the process of publication.

To bring the material to the ESRF facility, the specimens will be packed in hand-carried photographic cases with custom built archival foam liners – these liners will be cut to the dimensions of the specimens and each specimen will be isolated in its own pocket so as to minimize breakage. Specimens will be stored in the ESRF BM-18 safe during the experiment, and only removed for scanning and inspection. Specimens will be returned immediately after scanning to the Wits ESI.

Travel with the specimens will be via flights from OR Tambo to CDG, then to Lyon, and then via Flix Bus from Lyon to the ESRF. The return trip will follow the same route. All travel itineraries are provided as appendices.

Statement why this study cannot be done in South Africa:
South Africa does not have a synchrotron facility; therefore, the study cannot be done here. The ESRF is currently the only world beamline to offer the combination of high-resolution, phase contrast, and large specimen size, and the longstanding agreement between the ESRF and the South African NRF makes it the ideal synchrotron facility for this experiment.