Extended Data Fig. 7: Biogeographic dispersal model with individual results of sampling sensitivity tests.

a, The dispersal pattern of early dinosaurs from high-latitude southern Pangaea is robust to the possibility of increased sampling of Carnian dinosaurs in other regions of Pangaea; the same general pattern of restriction, dispersal, and later restriction holds with the addition of hypothetical sampling elsewhere in Pangaea. b, The dispersal pattern of early dinosaurs from high-latitude southern Pangaea is consistent among differing phylogenetic topologies—20 trees taken from the posterior distribution of trees from the Langer et al. Bayesian analysis show consistent patterns even given a wide variety of topologies. c, The dispersal pattern of early dinosaurs from high-latitude southern Pangaea is consistent among differing phylogenetic topologies and sensitivity analyses, including the Baron et al. and Cabreira et al. Bayesian trees, if Mbiresaurus raathi is Norian in age, if Lessemsaurus and Ingentia are included in the analysis, and if Bagualosaurus or Guaibasaurus-aged theropods are recovered from South America. Our hypothesis will be falsified if an extremely diverse dinosaurian assemblage is recovered from the Carnian of northern Pangaea (northern Carnian dinosaur assemblage). d, Results of the model variant simulating arid belts in the tropics of both northern and southern Pangaea (see Methods); the same general pattern holds, and this pattern is disrupted a diverse hypothetical northern dinosaurian assemblage, and three hypothetical northern sauropodomorphs.