paleogeeninen

Paleogeeninen refers to the earliest period of the Cenozoic Era, spanning from 66 million to 23 million years ago. This period followed the Cretaceous–Paleogene extinction event, which wiped out non-avian dinosaurs. The Paleogene is further divided into three epochs: the Paleocene, the Eocene, and the Oligocene.

During the Paleocene, early mammals began to diversify and increase in size, taking advantage of the ecological niches left vacant by the dinosaurs. Tropical and subtropical conditions prevailed across much of the Earth, with diverse flora and fauna.

The Eocene was characterized by warmer global temperatures than any other period in the Cenozoic. This led to extensive forests and the evolution of many modern mammal orders, including whales, bats, and ungulates. Significant continental drift also occurred, with the separation of Antarctica from South America and Australia.

The Oligocene saw a cooling trend and the formation of ice sheets in Antarctica. This climate change led to shifts in vegetation, with grasslands becoming more widespread. Mammals continued to evolve, with the emergence of larger herbivores and the diversification of primates. The Paleogene as a whole marks a critical transition in Earth's history, setting the stage for the subsequent evolution of modern life.