Tertiary Period

Tertiary Period, the lower division of the Cenozoic era, extending from the end of the Cretaceous to the beginning of the Quaternary, from 70,000,000 to 2,000,000 years ago. It is divided into 5 epochs: Paleocene, Eocene, Oligocene, Miocene, and Pliocene. The early Tertiary period was characterized by a large amount of mountain building (Andes, Alps, Hymalayas). In this period marsupials and placental mammals diversified and began to take a more modern appearance. Also during this time, worldwide climates began to gradually change into today's climatic zones.