The Age of the Sauropods – Very Large Dinosaurs. Note the numerous marine creatures – Belemnties, Fish and Crayfish.
At the beginning of the Jurassic Period Pangaea began shifting into two landmasses, Gondwana and Laurasia. This caused the climate to change from dry to humid and once again large rainforests dominated the landscape. The Jurassic was ruled by the dinosaurs. The plated Stegosaurus and the 85 ft Brachiosaur both roamed the earth at this time. They were giants. The first birds appeared and mammals emerged.
The Stegosaurus was a large, heavily built, herbivorous quadruped that had bony spikes on its back. They
were not sharp but instead were probably used for defense in another way or to regulate the creature’s body heat. Stegosaurus has been found throughout North America and Europe.
Marine life was still thriving and many fossils we find from this time are from creatures that lived in
the oceans.
One of the most common marine fossils from this time period was the Belmnite. It was similar in
appearance to squid and had an ink sac. They did not have tentacles, only arms. They were efficient carnivores that caught small fish and were meals for larger marine reptiles.
The Lycoptera is a genus of fish that lived during the Jurassic period. There are many fossils found of
this fish. The Lycoptera were small fresh water fish that fed on Plankton and had numerous tiny teeth.
This is a fossil of a crayfish that lived during the Jurassic period. They survived several extinctions and are similar to ones we enjoy today.