Neogene

The Neogene Period is a unit of geologic time that spans from 23.03 million to 2.58 million years ago. It is the second period of the Cenozoic Era and follows the Paleogene Period. The Neogene is subdivided into two epochs: the Miocene and the Pliocene.

Key Characteristics:

• Climate: The Neogene Period is characterized by a gradual cooling and drying trend compared to the preceding Paleogene. The period saw the formation of ice sheets in Antarctica and the gradual expansion of grasslands and savannas at the expense of forests.
• Tectonics: Significant tectonic activity continued during the Neogene, including the ongoing uplift of the Himalayas, the formation of the Alps, and the opening of the Red Sea. The Isthmus of Panama formed during the Pliocene, significantly altering ocean currents and contributing to climate change.
• Life: Mammals diversified significantly during the Neogene, with the appearance and evolution of many modern groups, including primates, ungulates, and carnivores. Hominins, the ancestors of humans, evolved in Africa during the Neogene. Marine life also evolved, with the diversification of marine mammals and mollusks.
• Miocene Epoch (23.03 to 5.333 million years ago): A warmer period within the Neogene, witnessing the continued diversification of mammals and the spread of grasslands.
• Pliocene Epoch (5.333 to 2.58 million years ago): Characterized by further cooling and drying, the formation of the Arctic ice cap, and the appearance of early hominins. It is immediately followed by the Quaternary Period, which includes the present day.

The Neogene Period is significant for understanding the evolution of modern life, the development of the Earth's climate, and the tectonic processes that continue to shape the planet. The boundary between the Neogene and the subsequent Quaternary is often debated and defined differently by various geological organizations, focusing primarily on paleoclimate changes and the appearance of ice ages in the Northern Hemisphere.