Life Forms under the Mesozoic era

Toward the beginning of the Mesozoic Era there was a depleted ecosystem world-wide. Many of the old life forms had just gone extinct in the Permian Extinction, the world's largest mass extinction. This depleted state was followed by an explosion of new life forms, which included the dinosaurs and mammals, and later in the Mesozoic, the birds and flowering plants.

During the Mesozoic era, the Earth’s life forms were very different. The temperature was warmer, the seasons were very mild, the sea level was higher, and there was no polar ice. The landscape of the Mesozoic Era was also marked by substantial changes in vegetative patterns that altered erosional patterns involved in landscape evolution.