Cenozoic (66 Ma - present)

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The Cenozoic (‘Recent Era’) began 66 mya, following the mass extinction where non-avian dinosaurs and other terrestrial and marine fauna and flora had perished. The Cenozoic is often called the "Age of Mammals", as the mammals rapidly diversified to fill the ecological niches left vacant from the extinction of many groups at the end of the Cretaceous, although birds appear to be more diverse in living species than mammals. The Cenozoic era is divided into the Paleogene, Neogene and Quaternary periods respectively.

 

Earth started to look more like its modern self, with the continents moving to their modern positions. The Himalayas started forming during the Eocene, after the continental collision of India and Asia, and the final stages of formation of the Alps and Andes also took place.

As the Indian and Atlantic oceans continued expanding, the Tethys Sea closed, leaving leftover fragments like the Black sea and Mediterranean sea. Throughout the Paleogene, Antarctica drifted towards the south pole, and by the Oligocene, had began to accumulate its thick ice cap after the establishment of the Antarctic Circumpolar Current. After an interval of greenhouse conditions  in the Paleogene, a long period of cooling took place throughout the Neogene to the Quaternary, where drier grasslands spread at the expense of forests. As a result, lots of big and small herbivorous mammals and their predators had to adapt to life on the open plains.

 

As life took its modern shape both on land and in water, all the major orders of mammals had already appeared by the start of the Neogene. The herbivores and carnivores co-evolved to adapt to competition and the ever-changing climate. The Quaternary period is part of a continuous ice age, where intense glacial periods alternated with warmer interglacials (we are currently in an interglacial). Major changes in mammalian fauna took place near the end of the Pleistocene epoch, with the extinction of the Pleistocene megafauna. One of the most remarkable events to happen during the Cenozoic is the evolution of the Hominidae, a family of primates in which our own species had its origins – Homo sapiens.