The Pliocene epoch lasted from about 5.3 to 2.6 million years ago and is the last period of the Neogene period. It is characterized by significant climate changes, with global temperatures gradually cooling and the formation of polar ice caps. This epoch saw the development of modern ecosystems and the expansion of grasslands. During the Pliocene, many species of mammals and birds evolved, including early ancestors of humans, such as Australopithecus. The epoch also marked the rise of the Himalayas and the Isthmus of Panama, which significantly impacted ocean currents and climate patterns.