Describes the role of an oak tree in the ecology of the Pennsylvania forest in which it lives.

Describes how tide pools are formed and some of the plants and animals that can be found in them.

Examines the activities, plant and animal life, and climatic changes found in ponds.

What causes thunderstorms and lightning? Where and why do hurricanes form? How are blizzards more dangerous than other snowstorms? To answer these questions, you'll need to know about nature's most powerful weather events. Storms of all types and sizes occur around the globe. Each storm needs just the right combination of weather conditions to form and become dangerous-or even destructive. In this fact-packed book, discover how storms form, where...

How does a cloud form? When is the best time to see a rainbow in the sky? Why do ice cubes shrink in the freezer? The answers to these questions all involve water. So do the reasons why we have rain and snow. To understand weather, we have to know what happens to water at different temperatures, on the ground and in the air. In this fact-packed book, discover what happens when water changes from a liquid into a gas or a solid, and much more.

Describes the characteristics and life cycle of the giant saguaro cactus that grows in Arizona's Sonoran Desert.

Seals, otters, oysters, fish, pelicans, and sharks are a few of the animals that make up an ocean food web. But did you know that almost all ocean creatures depend on algae to live? Or that bacteria, crabs, and lobsters break down dead plants and animals into nutrients? See ocean food webs in action in this fascinating book.

Did you know that both electricity and light move in waves, like water does? What does electricity have to do with magnets? From Benjamin Franklin and Charles de Coulomb to Georg Ohm and James Joule, readers will be introduced to the basic principles of light, electricity, and magnetism in an illuminating way.

Discusses the causes of weather conditions, explains how meteorologists gather data for their forecasts, and details techniques used to forecast the weather.

Explains how scientists' observations of the stars led to the development of the big bang theory, a theory of how our universe was formed.