Neogene Period: 23-2.6 Million Years Ago
The Neogene Period is the second geologic period of the Cenozoic Era and extends from 23 to 2.6 million years ago. The Neogene Period is subdivided into the Miocene and Pliocene Epochs. Neogene is derived from the Greek terms meaning new neo and birth gene (Borror, 1988, pp. 42 & 62). There was a general cooling trend during this period. Grasslands expanded in this cool, drier climate. The grasslands had a significant impact on mammal evolution. Herbivores adapted to grazing on grasslands formed large herds. Many of the predators followed the new grazing species out into the grasslands. Some of the new grazers and their predators adapted to the new open environment by evolving great speed. Kelp forests evolved in some of the areas where oceans were cooling. Swimming mammals adapted to living in these new environments appeared such as otters and dugongs. The largest known shark, Carcharodon megalodon, flourished during this time.
Pliocene: 5.3-2.6 million years ago
Pliocene fossil wood has been discovered in diverse locations worldwide, shedding light on the plant diversity of that time. In North America, fossil wood specimens from the Pliocene have been found in the western United States and parts of Canada, revealing tree taxa such as oak, pine, and beech. Europe has also yielded significant findings, with Germany, Italy, and the United Kingdom providing fossil wood samples representing oak, beech, and cypress. South America's Pliocene fossil wood in Argentina and Chile includes tree taxa like Araucaria and Nothofagus. Additionally, Asia (India, China, Japan), and Australia have contributed to our understanding of Pliocene plant diversity through the discovery of fossil wood, highlighting tree taxa such as oak, beech, pine, eucalyptus, casuarina, and acacia. These global findings offer valuable insights into the plant composition and ecosystems of different regions during the Pliocene epoch.
Miocene: 23 to 5.3 million years ago
During the Miocene epoch, fossil wood from various regions around the world, including Asia, reveals the presence of diverse tree taxa. Common tree families represented in Miocene fossil wood include oak (Quercus), beech (Fagus), pine (Pinus), and magnolia (Magnoliaceae). In addition, Miocene fossil wood findings from Asia highlight the presence of several distinct tree taxa. These include Dipterocarpaceae, a family dominant in Southeast Asian rainforests, as well as Agathis (kauri trees), Casuarinaceae (casuarina trees), and Acacia from the Fabaceae family. These Asian findings contribute to our understanding of the rich plant diversity and ancient ecosystems of the region during the Miocene epoch.
Borror, D.J. (1988). Dictionary of Word Roots and Combining Forms. California: Mayfield Publishing Company.