The Earth Heroes books feature the youth, careers and lasting contributions of some of the world's greatest naturalists and environmentalists. This is the first in a series of meticulously researched books that introduces influential people involved in the preservation of wild places to upper elementary and middle school children. In almost all cases they were scientists as well as activists and authors. Their lives show how they shared their scientific skills and knowledge with the public to make lasting contributions to the world. This volume includes eight historic and contemporary greats: Henry David Thoreau, whose writings formed the basis for the environmental movement; John Muir, the extraordinary naturalist; Theodore Roosevelt, who engaged the government in conservation; Aldo Leopold, instrumental in creating the world's first wilderness preserve; Richard St. Barbe Baker, who spearheaded the first major international reforestation campaign; Mardy Murie who worked to preserving huge wilderness tracts in Alaska; David Suzuki, eminent Canadian scientist and broadcaster; and Wangari Maathai, a Kenyan woman who focused on the social impact of the environment. The second and third in the series will be about environmental heroes that preserved the oceans and wildlife.