Reassessment of a Historical Collection of Sauropod Dinosaurs from the Northern Morrison Formation of Wyoming, with Implications for Sauropod Biogeography

The Upper Jurassic Morrison Formation of the western United States preserves one of the best-known Mesozoic paleoecosystems worldwide. The formation crops out over an area from New Mexico and Oklahoma to Montana and Utah and encompasses a time span of approximately eight million years. Recent studies indicate a high diversity of gigantic, herbivorous sauropod dinosaurs, but the geographic and temporal distributions of species or even genera of...