Image of Western Interior Seaway.
Info before video: This Prehistoric Inland Sea existed in what is now the Great Plains of North America. The sea split the North American Continent into two big islands, to the west is Laramidia, and to the east is Appalachia. The Western Interior Seaway lasted from the early late Cretaceous (100 Million Years Ago) to the earliest of the Paleocene (66 Million Years Ago)
Laramidia fauna: This island was home to the Tyrant lizard and its other species, the Tyrannosaurus Rex, Nanuqsaurus, Daslpetosaurus, and Teratophoneus as the Tyrannosaurinae as well as some Albertosaurinae such as Albertosaurus and Gorgosaurus. Some “duck-billed” Hadrosaurs, some sauropods, and armored dinosaurs.
Appalachia Fauna: This island was also home to Tyrannosaurs, Dromeosaurs like Dakotaraptor, and more advanced Allosaurinae. Some other dinosaurs like ceratopsians, and other herbivores.
Both islands had their fair share of lizards, amphibians, small mammals, and flying reptiles.
Here’s the video link for the Western Interior Seaway: https://youtu.be/SpoqgjauXSg?si=B-nLXAx2Pm6U1axk