The role of tectonics and environment on the distribution of dinosaur diversity

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Dinosaurs first appeared approximately 230 million years ago and rapidly became globally distributed. However, it is currently unknown where on Earth they first appeared, and what effect the breakup of the super-continent Pangaea had on their diversity and distribution. Determining the impact of Pangaean fragmentation on the distribution of life is one of the central goals of biogeography, but fierce debate and uncertainty plagues this field. To quantitatively evaluate dinosaurian evolutionary and biogeographic history, I will infer a timecalibrated supertree of the group's evolutionary relationships and use this alongside an existing dataset of dinosaur fossil occurrences. I will then apply a series of state-of-the-art analytical methods, including sampling standardisation, network analysis, and Likelihood (BioGeoBEARS) and Bayesian (PyRate) approaches. Information on sampling biases (e.g. areas that lack suitable sedimentary rocks for preserving dinosaurs) and palaeogeographic/environmental barriers and filters to dispersal (e.g. published data from past continental configurations and palaeoclimatic models) will also be incorporated into analyses, factors that have largely been ignored in previous studies. These analyses will enable me to evaluate the relative roles of vicariance and dispersal on the distribution of dinosaurs through time, including testing whether some clades likely underwent transoceanic dispersal.