Considered by many to be the father of wildlife ecology, Aldo Leopold (1887 - 1948) was a conservationist, forester, philosopher, educator, writer, and outdoor enthusiast. Among his best-known ideas is the "land ethic," set out in A Sand County Almanac (1949), which calls for humankind's 'ethical community' to expand and include 'soils, waters, plants, and animals, or collectively: the land,' and 'changes the role of Homo sapiens from conquerer of the land-community to plain member and citizen of it'.