My main research interest is understanding the effects of mass extinction events on land. Mass extinctions are major perturbations of the biosphere resulting from a wide range of different causes (e.g., glaciations, global warming, volcanic eruptions, bolide impacts). However, links between these broad causal factors and ecological disturbances are difficult to characterize. This is due to the latter unfolding on much shorter timescales than typical paleontological studies. In addition, the nature of the terrestrial record (e.g., depositional hiatuses, geographically widespread rock record) also makes mass extinction research particularly challenging. Finer time resolutions are essential, and I have used my expertise in fieldwork, stratigraphy, and museum collections metadata collation to achieve this high level resolution. I consider the compilation of spatial, temporal, and biological metadata for thousands of fossils a ‘Paleoinformatics’ approach. The positioning of fossils into meter-level bin intervals, at hundreds of thousands of years’ resolution, correlates various geographic locations across these hugely important evolutionary events in the history of life on Earth.
My first research project focused on the origin of Lystrosaurus bonebeds found in Earliest Triassic rocks of South Africa's Karoo Basin. Over two years, I joined Prof. Roger Smith and the Iziko South African Museum field team multiple times collecting fossils and stratigraphic data. By 2012 I graduated with a Masters in Geology (MSc). This work instilled a passion for extinction events and I continued this work on the Permo-Triassic extinction by taking up a PhD (funded by the National Research Foundation) based at the University of the Witwatersrand in Johannesburg. Under the supervision of Prof. Bruce Rubidge (Evolutionary Studies Institute, ESI) and Prof. Roger Smith, I pioneered my Paleoinformatics approach that combines interdisciplinary metadata to investigate the events occurring in the Karoo Basin just prior to and during the End-Permian mass extinction event; which broke the incumbency of synapsid dominated ecosystems and allowed the opportunity for archosaurs to diversity.
For my postdoctoral fellowship based at the ESI (funded by the Center for Excellence in Palaeosciences) I joined Prof. Jonah Choiniere's lab to help answer questions concerning another equally important extinction event preserved in the Karoo Basin at the Triassic-Jurassic Boundary. During two postdoctoral fellowships, I was able to apply the same approach by creating a similar time-calibrated framework to collections-based metadata, and raw field data to improve our understanding of the extinction event at the end of the Triassic period. This research also had a trickle-down effect where I was able to collaborate with my labmates in answering other important palaeobiological questions that have up until this point been difficult to answer (e.g. species richness and disparity of tetrapods between the Triassic and Jurassic and whether increased aridity/body size maxima drove these changes; stratigraphic ranges of tetrapod taxa and inferred extinction and origination events; geographic distribution of tetrapod taxa). My work allowed for stratigraphic correlation of key field sites and index taxa across the inferred Triassic-Jurassic Boundary, allowing me to pinpoint the earliest appearance some of the oldest dinosaur-dominated ecosystems and mammal-line mammaliaformes from South Africa and Lesotho. This framework has also allowed me to correlate other Karoo-aged basins in other parts of southern Africa. For example, I along with collaborators from the National Museums and Monuments, Zimbabwe Geological Survey, Natural History Museum of London, and University of the Witwatersrand, revised the stratigraphy of the oldest true sauropod, Vulcanodon, which demonstrated diversification of the clade began millions of years earlier than previously understood. This publication was given the Phaup award from the Geological Society of Zimbabwe, which acknowledges significant advancements in the understanding of Zimbabwe’s geology. Additionally, we also discovered the first Sub-Saharan phytosaur, and reconstructed the palaeoecosystems of Late Triassic fossil-bearing sites on the shores of Lake Kariba in Zimbabwe.
Recently, thanks two postdoctoral fellowships from the Women in Science Board and Grainger Bioinformatics Center at the Field Museum of Natural History, I am applying my multi-index approach to test the assemblage zone framework of the Karoo Basin, and better quantify the diversity dynamics of the End-Permian mass extinction event. Recently this research was published in the Proceedings of the National Academy of Sciences (PNAS) in collaboration with Kenneth Angielczyk (Curator of Paleomammalogy), Roger Benson (University of Oxford), Jennifer Botha (National Museum, Bloemfontein), Roger Smith (Iziko South African Museum, Cape Town), and our joint collecting and preparation teams. We characterized faunal assemblage dynamics across the Permo-Triassic Boundary in the Karoo Basin and show the extinction on land was a protracted event (~1 Ma), which is in contrast to the more rapid marine event. We also identify a post-extinction assemblage of short-lived species symptomatic of ecosystem instability rather than rapid recovery. We also challenge the conventional wisdom about the extinction’s best-known survivor, the dicynodont therapsid Lystrosaurus that shows a long-term trend of increasing abundance that initiated in the latest Permian rather than in the post-extinction early Triassic as had been previously assumed. Thus, my geological expertise in providing time calibrated frameworks in the rock record has allowed me to contextualize a multitude of research questions relating to changes to palaeoenvironment and basin dynamics, palaeobiological and evolutionary rates. I also enriched and increased the availability of metadata for over 10,000 South African fossil specimens housed in 22 collections repositories around the world. This facilitate decades of future research.