The Tertiary is a geological period of the Cenozoic era, beginning approximately 60 million years ago and spanning 30 million years. It divides into five epochs: the Paleocene, Eocene, Oligocene, Miocen, and Pliocene. The Tertiary marks the emergence of birds and mammals and the geological formation of the highest mountain chains on Earth, such as the Himalaya, the Andes, Rocky, and Alps mountain ranges.

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