KANSAS OCEAN LIFE ART POSTER

The Western Interior Seaway, sometimes called the Niobrara Sea, was a vast inland sea that divided North America in the mid to late Cretaceous Period. It lasted for about 60 million years and eventually disappeared in the Paleocene due to regional geologic uplift and the rise of the Rocky Mountains. Some of the best fossils from this period are found in the chalk rocks of western Kansas.

The seaway was vast and shallow, stretching north to south for 2,000 miles. It was filled with a fantastic array of abundant marine life, including giant marine reptiles such as short and long-necked plesiosaurs and mosasaurs that grew up to 60 feet long. Other marine life included large sharks such as Cretoxyrhina and the giant shellfish-eating Ptychodus thought to be over 40 feet long.  It was home to a whole host of fearsome carnivorous fishes like Xiphactinus, Enchodus and Protosphyraena.

Pterosaurs and rare seabird fossils have also been preserved in the chalk beds. Invertebrates like giant squid, enormous clams and beautifully spiraled ammonites were also common inhabitants of this long-lost world.