The Age of Mammals, also known as the Cenozoic Era, is characterized by the emergence and diversification of mammals following the extinction of dinosaurs. Spanning from 66 million years ago to the present, this era saw mammals evolve into dominant terrestrial animals, showcasing significant adaptations and diversification. The Cenozoic also witnessed the development of modern ecosystems, with mammals occupying various ecological niches and playing crucial roles in the Earth's biodiversity.