Shallow seas formed, dividing some continents. In the Late Cretaceous, for example, the Western Interior Seaway split North America into two landmasses. At its largest this sea was more than 3,000 ...

During the Late Cretaceous, much of western Colorado was part of the vast Western Interior Seaway, which divided North ...

Xiphactinus trolled an ancient ocean called the Western Interior Seaway, which covered much of central North America during the Cretaceous. Though long extinct, if alive today the bony fish would ...

The animal lived about 70 million to 75 million years ago in a part of the state that would likely have been a swampy environment.

The Interior Seaway, for example ... of dinosaur species for several million years leading up to the end of the Cretaceous. Sea Level The presence of 65- to 70-million-year-old fossilized ocean ...

Eberle said that finding mammal fossils from the Cretaceous period doesn't happen ... been very close to the coast of the Western Interior Seaway." She said the area of Colorado where this fossil ...

For most of the Cretaceous, Canada’s prairie provinces were sitting deep underwater. A giant inland sea cut right across North America. Known as the Western Interior Seaway, it ran north to ...

Paleoartistic reconstruction of a plioplatecarpine mosasaur from the Western Interior Seaway with 3D laser scan and reconstructed life-like skull (credit artwork: Henry Sharpe).