The Tertiary Period is a division of the Cenozoic Era, which began about 65 million years ago and continues to the present day. The Tertiary Period is divided into three epochs: the EOCENE (6 letters), the Pliocene (8 letters), and the Neogene (7 letters). The EOCENE epoch lasted from 56 to 33.9 million years ago and was characterized by the emergence of modern mammals and birds. The Pliocene epoch lasted from 5.3 to 2.6 million years ago and saw the development of grasslands and the expansion of human ancestors. The Neogene epoch lasted from 2.6 million years ago to the present day and is marked by the development of Homo sapiens and the spread of agriculture.