EXTINCTION

There were several extinction events during the Jurassic period. The biggest event triggered the beginning of the Jurassic and it eliminated most of the Mammal-Like Reptiles that had been competing with dinosaurs to fill certain niches in the evolving ecosystem. This in effect allowed the dinosaurs to embark upon a cycle of evolutionary domination that would last for more than 160 million years.

Another event occurred approximately 22 million years after the start of the Jurassic. This event eliminated the early Jurassic creatures such as Dilophosaurus and made way for the larger predators and plant-eaters. It is believed that, although there were certainly extra terrestrial objects like comets and asteroids periodically impacting the Earth and causing destruction on a fairly large scale, this extinction event was most likely caused by geologic activity.

The final extinction event at the end of the Jurassic seemed to have had more of an effect on sea life than it did on land animals like the dinosaurs. Plesiosaurs, Tylosaurs and other large marine reptiles suffered a medium extinction that could have been the result of changing ocean currents and temperatures caused by the separation of Pangaea.