The Cenozoic Era is the most recent of the three major eras in Earth's history, spanning from about 66 million years ago to the present. It is often referred to as the "Age of Mammals" due to the diversification and dominance of mammalian life forms during this era. The Cenozoic Era is divided into three periods: the Paleogene, Neogene, and Quaternary.
The Paleogene Period began about 66 million years ago and lasted until approximately 23 million years ago. It is further divided into the Paleocene, Eocene, and Oligocene epochs. During the Paleogene, the Earth experienced significant changes in climate and the evolution of early mammals, birds, and flowering plants.
The Neogene Period followed the Paleogene and extends from around 23 million years ago to 2.6 million years ago. It is comprised of the Miocene and Pliocene epochs. This period witnessed the further diversification of mammals, the rise of grasslands and savannas, and the appearance of early hominids, including our human ancestors.
The Quaternary Period is the most recent period of the Cenozoic Era, beginning around 2.6 million years ago and continuing to the present day. It is characterized by the onset of major glaciations and the evolution of Homo sapiens. The Quaternary Period is further divided into the Pleistocene and Holocene epochs.