Today, ice covers Earth's North and South poles. These ice caps are called polar glaciers. During an ice age, the polar glaciers grow larger. At the height of an ice age, glaciers may cover as much as a third of the Earth. Canada, the northern United States, northern Europe, and northern Russia all get covered by ice. This ice can be more than a mile (1.6 kilometers) thick.
Much of the world's water gets frozen to make these glaciers. This water comes from the oceans, and sea level drops as a result. Places that had been under water become dry land. Many plants and animals adapt to these changes. Those that do not adapt die out.
During the last ice age, animals with warm shaggy coats flourished. For example, the woolly mammoth, a large elephant-like animal, roamed icy areas of Earth. The mammoths probably used their huge tusks to scrape away the snow in search of plants to eat. Their thick woolly coats protected them from the cold.
Much of the world's water gets frozen to make these glaciers. This water comes from the oceans, and sea level drops as a result. Places that had been under water become dry land. Many plants and animals adapt to these changes. Those that do not adapt die out.
During the last ice age, animals with warm shaggy coats flourished. For example, the woolly mammoth, a large elephant-like animal, roamed icy areas of Earth. The mammoths probably used their huge tusks to scrape away the snow in search of plants to eat. Their thick woolly coats protected them from the cold.
