Book excerpt: Answering intriguing questions such as Why does the largest river system in North America meander across the middle of the continent? and How does such a system relate to the rugged Rocky Mountains?, this fun-filled book delves into the majestic Great Plains region. The chapters concisely clarify the interrelated subjects of terrain, climate, and the great movements of the earth itself while illustrating the important changes that are still occurring in the area’s rivers, lakes, plains, and unpredictable weather. Brimming with fascinating facts, educational sidebars tell how earthquakes in New Madrid, Missouri caused waves to go upstream in the Mississippi River; why and how tornadoes form; and how invasive species are threatening the Great Lakes and what people are doing about it.