Early ammonites had simple suture lines traced across their shells, while the sutures on species from the Cretaceous period (145 to 66 million years ago) formed intricate patterns that may have ...

3 min read Continents were on the move in the Cretaceous, busy remodeling the ... long-necked and toothy marine reptiles terrorized fish, ammonites, and mollusks in the seas; pterosaurs and ...

These animals are known from the Jurassic Period, from about 200 million years ago. Most ammonites died out at the same time as the non-avian dinosaurs, at the end of the Cretaceous Period, 66 million ...

Ammonites are primarily found in marine sedimentary deposits, where they were once abundant during the Late Cretaceous period. This was the time of T-Rex when massive dinosaurs roamed the land.

Nipponites mirabilis are some of the most unusual-looking ammonites. Another heteromorphic species, fossils have been found in rocks that date to the Late Cretaceous in Japan. The unusual alternating ...

Exquisitely preserved fossils of a shark that thrived during the Cretaceous period appear to ... such as large ammonites and sea turtles.” While the individuals they studied are small, at ...

A Cretaceous Period bird called Vegavis iaai pursuit diving for fish in the shallow ocean off the coast of the Antarctic peninsula, with nautilus-like ammonites and marine reptiles called ...