The Ice Age refers to a series of glacial periods during the Earth's history, characterized by the expansion of ice sheets and glaciers. The most recent Ice Age, known as the Pleistocene, began around 2.6 million years ago and lasted until about 11,700 years ago, significantly shaping the planet's landscape and ecosystems. During the Ice Age, large mammals such as the woolly mammoth and the saber-toothed cat roamed the Earth. As temperatures rose and the ice began to melt, these species faced extinction, while others adapted to the changing environment, leading to the diverse wildlife we see today.