Ankylosaurus would have been unable to knock down trees like modern elephants do. It was also incapable of chewing bark and thus unlikely to have practiced bark stripping. As an adult, Ankylosaurus does not appear to have congregated in groups (though some ankylosaurs appear to have congregated when young). It is therefore improbable that Ankylosaurus was able to modify the landscape of its ecosystem in the way elephants do; hadrosaurids may instead have had such an "ecosystem engineer" role. The formations where Ankylosaurus fossils have been found represent different sections of the western shore of the Western Interior Seaway dividing western and eastern North America during the Cretaceous, a broad coastal plain extending westward from the seaway to the newly formed Rocky Mountains. These formations are composed largely of sandstone and mudstone, which have been attributed to floodplain environments. The regions where Ankylosaurus and other Late Cretaceous ankylosaurs have been found had a warm subtropical/temperate climate, which was monsoonal, had occasional rainfall, tropical storms, and forest fires. In the Hell Creek Formation, many types of plants were supported, primarily angiosperms, with less common conifers, ferns and cycads. An abundance of fossil leaves found at dozens of different sites indicates that the area was largely forested by small trees. Ankylosaurus shared its environment with other dinosaurs that included the ceratopsids Triceratops and Torosaurus, the hypsilophodont Thescelosaurus, the hadrosaurid Edmontosaurus, an indeterminate nodosaur, the pachycephalosaurian Pachycephalosaurus, and the theropods Struthiomimus, Ornithomimus, Pectinodon, and Tyrannosaurus. See also Timeline of ankylosaur research References Notes Citations External links Ankylosaurids Late Cretaceous dinosaurs of North America Fossil taxa described in 1908 Taxa named by Barnum Brown Lance fauna Hell Creek fauna Scollard fauna Paleontology in Montana Paleontology in Wyoming Paleontology in Alberta Maastrichtian genus first appearances Maastrichtian genus extinctions Ornithischian genera