This page contains a Flash digital edition of a book.
A hungry pika chews on leaves it found among the rocks.


This seabird swims near a glacier.


Moving Mountains Standing on the glacier, it’s hard to feel how large and powerful it really is. Aſt er all, glaciers are the largest, most powerful moving objects on Earth. As they move over time, they can do some


extreme landscaping. T ey shape many of Earth’s landforms. Glaciers dig deep valleys. T ey carve troughs


in the ground. T ey grind away mountains. T ey bulldoze sand and gravel into ridges called moraines.


Signs of Life Glaciers change Earth’s surface in other ways, too. In some parts of Greenland and Antarctica, the ice is over 4 kilometers (2.5 miles) thick. T at’s a lot of ice and a lot of weight. T e ice is so heavy that it presses down on Earth’s crust. Beneath the ice, parts of the land have been pushed below sea level. Glaciers may look lifeless and icy. Yet they


are the heart of a lively ecosystem. Many plants and animals live on or near glaciers. Take pikas, for example. Pikas are small


mammals. T ey have ears like a mouse. T ey are as large as a squirrel. Many only live in piles of broken rock on glaciers. T ey run in and out of the rocks. T ey search for food, guard their territory, and watch out for predators. T ere are others animals that can only live


on or near glaciers. One type of seabird only nests on rocks next to glaciers. It blends into the gray backdrop to stay safe from predators. Koppes’s favorite glacier critter is a worm.


This ice worm lives inside the glacier. It comes to the surface to eat.


Ice worms are oddball animals that live inside glaciers. T ey squirm through the ice and come to the surface in the evening or early morning. Ice worms eat algae and bacteria that they find on the ice.


JANUARY-FEBRUARY 2013 21


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24