Born: April 21, 1838
Died: December 24, 1914
Occupation: Environmentalist, engineer, naturalist, writer, botanist, geologist
Biography: John Muir was a Scottish-born American naturalist, author, and early advocate of preservation of wilderness in the United States. His letters, essays, and books telling of his adventures in nature, especially in the Sierra Nevada mountains of California, have been read by millions. His activism helped to preserve the Yosemite Valley, Sequoia National Park and other wilderness areas.