Evolution of Brachiopod Species Diversity Across the PTB in Varied Palaeogeographic Settings

The study on biodiversity evolution and occurrences of organisms is of importance for the study of mass-extinction patterns and causes. Numerous works have documented and discussed the patterns and processes of the Permian–Triassic extinction, resulting in the proposition of a variety of scenarios concerning the nature of these extinction, including one-episode, two-episode and multiple-episode models (or even more complex processes) (Yang et al. 1991; Shen and Shi 1996, 2002; Jin et al. 2000; Feng et al. 2007; Shen et al. 2011; Song et al. 2013; Wang et al. 2014; He et al. 2015; Grasby et al. 2015).