It ended about 65 million years ago
The Mesozoic era ended with a massive impact caused by an asteroid hitting Earth, leading to the extinction of the dinosaurs.
Paleozoic - climate change Mesozoic - meteor
The Mesozoic era began roughly 250 million years ago, and ended 65 million years ago. (This Era ended because of the K.T. extinction)
Mesozoic
None. Dinosaurs first appeared in the Mesozoic Era, after the Paleozoic ended.
The Cenozoic era was not a subdivision of the Mesozoic era. The Mesozoic era is subdivided into the Triassic, Jurassic, and Cretaceous periods.
Mesozoic Era
The Paleozoic precedes the Mesozoic. And our current era, the Cenozoic, follows the Mesozoic.
An asteroid impact
It really wasn't an era. An Era was a much longer period of time. It was called the "Jurassic Period".
The Mesozoic Era is known as the Age of Reptiles.
The dinosaurs lived in the Mesozoic Era, which includes the Triassic, Jurassic, and Cretaceous periods. The first dinosaurs appeared in the late Triassic and went extinct at the end of the Cretaceous.