Mike Clinton
Introduction: Cenozoic Period Classification
The Earth’s history is divided into various geological time scales, which have been constructed based on the study of rock layers, fossils, and other geological evidence. One of the most significant divisions is the Cenozoic Era, which is the current geological era. It began about 66 million years ago and continues until the present day. The Cenozoic Era is divided into three periods: the Paleogene, Neogene, and Quaternary periods. These periods are further divided into epochs, which are subdivisions of geological time.
Geological Time Scale: Divisions and Subdivisions
The geological time scale is divided into eons, eras, periods, epochs, and ages. Eons are the largest units of time, followed by eras, which are divided into periods. Periods are then divided into epochs, and epochs are further divided into ages. Each epoch is characterized by specific geological events and the appearance and extinction of certain plant and animal species. The subdivision of geological time is based on the study of rock layers, fossils, and other geological evidence.
Cenozoic Era: An Overview
The Cenozoic Era is the most recent geological era and is also known as the Age of Mammals. It began about 66 million years ago when the dinosaurs went extinct and continues until the present day. During this era, the Earth’s climate shifted from a warm, humid climate to a cooler, drier climate. The Cenozoic Era is characterized by the evolution and diversification of mammals, birds, and flowering plants.
The Beginning of Cenozoic Era
The beginning of the Cenozoic Era was marked by a mass extinction event, which wiped out the dinosaurs and many other species. This event is believed to have been caused by a massive asteroid impact, which caused a global climate change and a loss of habitat for many species. In the aftermath of this extinction event, mammals emerged as the dominant land animals.
Epochal Division of Cenozoic Era
The Cenozoic Era is divided into three periods: the Paleogene, Neogene, and Quaternary periods. Each period is further divided into epochs, which are characterized by significant geological events, the evolution of new species, and the extinction of others. The division of the Cenozoic Era into these three periods is based on significant changes in the Earth’s climate, geology, and the appearance and extinction of certain plant and animal species.
Paleogene Period: The First Epoch
The Paleogene Period is the first epoch of the Cenozoic Era and lasted from about 66 million to 23 million years ago. It is characterized by a warm, humid climate, the emergence of new mammal species, and the extinction of many older species. During this period, the Earth’s continents began to move into their present-day positions.
Neogene Period: The Second Epoch
The Neogene Period is the second epoch of the Cenozoic Era and lasted from about 23 million to 2.6 million years ago. It is characterized by a cooler, drier climate, the diversification of mammal species, and the emergence of early human species. During this period, the Earth’s climate underwent significant fluctuations, including the formation of ice caps at the poles.
Quaternary Period: The Third Epoch
The Quaternary Period is the third and final epoch of the Cenozoic Era and began about 2.6 million years ago and continues until the present day. It is characterized by a series of ice ages, the emergence of modern human species, and the extinction of many large mammal species, including the woolly mammoth and saber-toothed cat.
Causes of Epochal Division
The division of the Cenozoic Era into three periods and their respective epochs is based on significant geological events, the evolution of new species, and the extinction of others. These events are believed to have been caused by changes in the Earth’s climate, geology, and the emergence of new species. The study of rock layers, fossils, and other geological evidence has helped scientists to understand the causes and effects of these events.
Conclusion: Significance of Cenozoic Era Division
The division of the Cenozoic Era into three periods and their respective epochs has helped scientists to understand the geological history of the Earth. It has provided a framework for the study of evolution, climate change, and other significant geological events. The division of the Cenozoic Era into these periods and epochs has also helped to establish a timeline for the emergence of modern human species and their impact on the Earth’s environment.