ASBOG Practice Exam

Which is the correct order of eras from youngest to oldest?

1. Mesozoic; Paleozoic; Cenozoic

2. Paleozoic; Mesozoic; Cenozoic

3. Cenozoic; Mesozoic; Paleozoic

4. Cenozoic; Paleozoic; Mesozoic

The correct answer is: Cenozoic; Mesozoic; Paleozoic

The correct order of geological eras from youngest to oldest is Cenozoic, Mesozoic, Paleozoic. This sequence is based on the established geological time scale, which organizes Earth's history into a hierarchy of time periods. The Cenozoic Era, often referred to as the "Age of Mammals," is the most recent era, starting approximately 66 million years ago and continuing to the present day. It follows the extinction of the dinosaurs, which marks the end of the Mesozoic Era. The Mesozoic Era, known as the "Age of Reptiles," came before the Cenozoic Era. It is divided into three periods—Triassic, Jurassic, and Cretaceous—and lasted from about 252 to 66 million years ago, characterized by the dominance of dinosaurs. The Paleozoic Era is the oldest of the three, preceding the Mesozoic Era and lasting from around 541 to 252 million years ago. It features significant developments in life on Earth, including the emergence of fish, amphibians, and reptiles. This understanding of the geological time scale is essential in fields such as geology, paleontology, and environmental science, providing a framework for studying Earth's history and