kvaternaarisiin

Kvaternaarisiin refers to the Quaternary period, the current and most recent geological period of the Earth's history. It began approximately 2.58 million years ago and continues to the present day. This period is characterized by significant climatic fluctuations, most notably the repeated glaciations, often referred to as ice ages. During these glacial periods, large ice sheets covered vast areas of the continents, drastically altering landscapes through erosion and deposition. The interglacial periods, which are warmer, have seen the retreat of these ice sheets.

The Quaternary period is further divided into two epochs: the Pleistocene and the Holocene. The Pleistocene epoch, which spanned from 2.58 million to 11,700 years ago, is known for the dominance of glaciation and the evolution and extinction of many large mammal species, known as megafauna. The Holocene epoch, beginning around 11,700 years ago, is the current interglacial period, marked by generally warmer temperatures and the rise of human civilization.

Key events and features of the Quaternary include the development of human ancestors, the migration of Homo sapiens across the globe, and significant changes in flora and fauna. The geological record of the Quaternary is relatively well-preserved, particularly in sedimentary layers, ice cores, and landforms created by glacial activity. Studying this period is crucial for understanding past climate change, evolutionary processes, and the impact of environmental shifts on life.