Quaternaryera

The Quaternary Era is the most recent geological era of the Cenozoic Era, beginning approximately 2.58 million years ago and extending to the present day. It is characterized by the Earth's climate cycles, including repeated glacial periods known as ice ages, interspersed with warmer interglacial periods. The defining feature of the Quaternary is the significant impact of these climate fluctuations on the planet's geology, biology, and environment.

During the Quaternary, much of the Earth's landmass was covered by massive ice sheets, leading to dramatic changes in sea levels and landforms. Glacial erosion carved out valleys and fjords, while glacial deposition created features such as moraines and outwash plains. The retreat of these ice sheets also led to the formation of large lakes and reshaped coastlines.

Biologically, the Quaternary Era witnessed the evolution and extinction of many species. Mammals diversified significantly, and hominins, the group that includes modern humans and their ancestors, emerged and evolved during this period. The changing climate forced species to adapt, migrate, or face extinction, leading to the current biodiversity we see today.

The Quaternary Era is further divided into two periods: the Pleistocene Epoch, which spanned from 2.58 million years ago to about 11,700 years ago and is largely defined by the recurring ice ages, and the Holocene Epoch, which began around 11,700 years ago and continues to the present, marked by a warmer interglacial climate. Human activity has become a significant geological force in the latter part of the Holocene, leading some scientists to propose a new epoch, the Anthropocene.