Аннотация:The characteristics of the late Maastrichtian Hell Creek dinosaur assemblage can be understood as resulting in part from the influences of an unusually broad, rich coastal plain with limited niches available for large herbivorous dinosaurs. They could further stem from a regional vegetational change from gymnosperm- to angiosperm-dominated forests and the displacement toward the north of a low-diversity, southerly chasmosaurine-hadrosaurine-dominated assemblage due to a regional warming trend.
