Cenozoics

The Cenozoic Era, often referred to as the Age of Mammals, is the most recent and current geological era in the Phanerozoic Eon, spanning from approximately 66 million years ago to the present day. It follows the Mesozoic Era and is divided into three periods: the Paleogene, Neogene, and Quaternary. The Cenozoic marks a significant shift in Earth's climate, biodiversity, and geological activity, shaping the modern world.

The Cenozoic began with the Cretaceous-Paleogene (K-Pg) extinction event, which wiped out the non-avian dinosaurs and many other species, allowing mammals and birds to diversify rapidly. Early Cenozoic climates were generally warm, with high sea levels and lush vegetation, particularly in polar regions. Over time, cooling trends led to the formation of ice sheets in Antarctica by the Eocene-Oligocene boundary (~34 million years ago) and later in the Northern Hemisphere during the Quaternary.

Mammals, which had been relatively minor players during the Mesozoic, became dominant during the Cenozoic. This era saw the evolution of modern mammalian orders, including primates, ungulates, carnivores, and cetaceans (whales and dolphins). The diversification of flowering plants (angiosperms) also accelerated, influencing ecosystems and further driving mammalian evolution.

The Neogene period (~23 million years ago to 2.6 million years ago) witnessed the rise of grasses and savannas, which favored the evolution of grazing mammals and large predators. Human ancestors first appeared in the late Miocene, around 6–7 million years ago, marking a pivotal moment in evolutionary history.

The Quaternary period, which includes the current Holocene Epoch, is characterized by repeated glacial and interglacial cycles, significantly influencing human migration, culture, and adaptation. The Cenozoic continues today, with ongoing anthropogenic impacts reshaping ecosystems at an unprecedented rate. This era remains crucial for understanding Earth's recent geological and biological history.