Cenozoic Era

The Cenozoic era is the current and most recent of the three major eras of the Earth's geological history, spanning from about 66 million years ago to the present. It is also known as the "Age of Mammals" due to the significant diversification and dominance of mammalian life forms during this era.

Divisions of the Cenozoic Era

The Cenozoic era is divided into three periods:

1. Paleogene Period: This period spans from about 66 million years ago to 23 million years ago. It includes the Paleocene, Eocene, and Oligocene epochs.
2. Neogene Period: This period spans from about 23 million years ago to 2.6 million years ago. It includes the Miocene and Pliocene epochs.
3. Quaternary Period: This period spans from about 2.6 million years ago to the present. It includes the Pleistocene and Holocene epochs.

Key Events and Characteristics

During the Cenozoic era, several key events and characteristics shaped the Earth's geological and biological landscape:

• Climate Changes: The Cenozoic era saw significant fluctuations in global climate, including periods of cooling and warming, as well as the onset of ice ages during the Quaternary period.
• Continental Drift: The continents continued to drift and take on more familiar positions, leading to the formation of modern geographical features and ecosystems.
• Biological Diversification: Mammals, birds, and flowering plants experienced rapid diversification and adaptive radiation, leading to the emergence of modern faunal and floral communities.
• Extinction Events: The Cenozoic era witnessed several notable extinction events, including the Cretaceous-Paleogene extinction event, which led to the demise of non-avian dinosaurs and the rise of mammals as dominant terrestrial vertebrates.

Study Guide

To study the Cenozoic era effectively, consider the following key topics and concepts:

1. Geological and biological events during each period of the Cenozoic era.
2. Major animal and plant groups that emerged and diversified during the Cenozoic era.
3. Impact of climate change on the evolution and distribution of life forms.
4. Notable extinction events and their effects on the Earth's ecosystems.
5. Role of continental drift in shaping the Earth's geography and biogeography.
6. Comparison of the Cenozoic era with preceding geological eras in terms of major evolutionary and environmental changes.