How did the environment change in the Mesozoic age? How did this impact on animal life? By Tia Tudehope Stage 2

The Mesozoic Age The Mesozoic age is divided into three time periods:  The Triassic period ( million years ago)  The Jurassic period ( million years ago)  The cretaceous period ( million years ago)

Changes… The Mesozoic era is a time when the plants and animals in the world changed a lot from how they were in earlier times. Flying reptiles and birds first appeared during the Mesozoic Era. The Mesozoic era is often called the age of reptiles. This is because the reptiles were the most dominant animals in this era. The reptiles changed into large land-dwelling dinosaurs of the Jurassic and Cretaceous periods.

Changes… During the Mesozoic Era, the continents gradually moved from being joined together to their present place and shape. This movement caused changes in plants and animals as they got used to their new environments. The climate was very warm and this played a part in the changes to animals and the creation of new animal species.

Changes that led to extinction About 90-96% of marine species and 70% of land creatures became extinct in the Triassic period. This period is also known as the “great dying” because it is considered the biggest mass extinction in the history of the earth. In the cretaceous period a further 50% of all creatures became extinct, including all of the non- flying dinosaurs.

The Triassic period was very hot and dry. Sea levels began to rise in the Jurassic period. This caused more humid weather and there were fewer deserts. The warmer temperatures saw the larger animals begin to disappear, while the smaller animals got used to the different climate. Birds and mammals did well. Climate

The most common animals in the Mesozoic era were dinosaurs and water reptiles. The first birds and mammals appeared in the Jurassic period. Mammals were dominated by the reptiles until the end of the Mesozoic era, when the dominance of reptiles was ended by the extinction of the dinosaurs. Animals

The Mesozoic era was a time of great change for plants.  The Triassic period was dominated by ferns and other unusual plants. Conifers and pine trees appeared in the early Triassic period.  By the middle of the Cretaceous period the earliest flowering plants, deciduous trees and grasses appeared, taking over from other plants. Plants

The dramatic changes to temperature led to many plant species dying. This affected plant eating animals (herbivores). These animals lost their food source and died. When these animals died, the meat eating animals (carnivores) lost their food source and many of these animals could not survive. Rising sea levels changed the environment. Some animals were able to adapt to the changes, many of which still exist today, e.g. of crocodiles. Those that weren’t able to adapt became extinct. Conclusion

Mesozoic Era Mesozoic Era Timeline 70% of land animals became extinct 90-96% of marine animals became extinct First birds and mammals appeared Flowering plants and grasses appeared Conifers and Pine trees appeared Sea levels rose 50% of all remaining animals became extinct Triassic Period 245 – 208 million years ago Jurassic Period 208 – 146 million years ago Cretaceous Period 146 – 65 million years ago

Thank You Tia Tudehope Stage 2