More facts about the Jurassic Period

The Jurassic period is one of the three periods of the Mesozoic Era (a time in history when dinosaurs lived). It came after the Triassic period and before the Cretaceous period.

Triassic (250-201 mya)

Jurassic (201-145 mya)

Cretaceous (145-66 mya)

Have you heard of the famous Tyrannosaurus rex? Well, here’s a quick fact for you:

The T-rex actually lived in the Cretaceous period, not the Jurassic period! That’s a fun fact to share with your friends. But let’s learn some more cool things.

The name Jurassic

The Jurassic period is named after the Jura Mountain range which lies between Switzerland and France. During this time layers of limestone rock were being formed.

The Pangaea split

The splitting of Pangaea was one of the most important events during the Jurassic period. The supercontinent first split into two continents:

Laurasia: the northern part (made up of North America, Europe and Asia).

Gondwana: the southern part (made up of South America, Africa, India, Australia and Antarctica).

Pangaea continued to separate throughout the Jurassic period. This caused volcanoes to erupt along the seafloor where the continents were breaking apart.

Laurasia broke up into North America and Eurasia and Gondwana split into an eastern part (with Antarctica, Madagascar, India and Australia) and a western part (with Africa and South America).

New oceans began to flood the spaces in between the continents. Mountains rose on the seafloor, pushing sea levels higher and higher onto the continents.

All this water made the climate more humid and subtropical and much less dry. Deserts started to become greener, ferns and ginkgos grew in many areas and small palm-like trees called cycads grew abundantly. Because of this, the Jurassic period is sometimes called the 'Age of Cycads'. 

With all these new continents, there were more coastlines for life to evolve. Isn’t that amazing!

Not the only ones

If you think that dinosaurs were the only ones around during the Jurassic period, then you would be wrong. There were plenty of small, nocturnal mammals. Almost all of them were herbivores (plant eaters), insectivores (insect eaters) or frugivores (fruit eaters).

The oceans were filled with ammonites and cephalopods. Ichthyosaurs and Plesiosaurs remained the dominant water predators. 

Ammonite fossils are some of the most abundant fossils found, you can even buy them at museums. 

During the Jurassic period, something truly amazing happened. A branch of dinosaurs started evolving into the first birds and the first butterflies came to life.

At the beginning of this period, most dinosaurs were smaller but by the end of the Jurassic period, carnivorous dinosaurs had become much bigger, so they could hunt huge plant-eating dinosaurs.

The minor extinction

Towards the end of the Jurassic period there was another mass extinction, no way near as bad as the extinction before, but still strong enough to wipe out most bivalve molluscs of the time. Bivalves are animals like clams that have two shells hinged together.

Did you know?

• Archaeopteryx is one of the earliest bird fossils. It had both dinosaur and bird features, including a long, bony tail, sharp teeth and feathers.
• Some of the earliest salamander fossils date back to the Jurassic period.
• Siderops, a long, crocodile-like amphibian, lived during the Jurassic period in what is now Australia.