Evolutionary rates of mid-Permian tetrapods from South Africa and the role of temporal resolution in turnover reconstruction

The Main Karoo Basin of South Africa contains a near-continuous sequence of continental deposition spanning 45 million years from the middle Permian to the Early Jurassic. The terrestrial vertebrates of this sequence provide a high-resolution stratigraphic record of regional origination and extinction, especially for the middle–late Permian. Until now, data have only been surveyed at coarse stratigraphic resolution using methods that are biased by non-uniform sampling rates, limiting our understanding of the dynamics of diversification through this important time period. High-resolution data now cross the mid-to-late Permian transition; to these we apply robust methods (gap-filler and modified gap-filler rates) for the inference of patterns of species richness, origination rates and extinction rates to a subset of 1321 securely-identified fossil occurrences resolved to approximately 50 metre stratigraphic intervals. This dataset provides an approximate time resolution of 0.3-0.6 million...