A seminal moment in mankind's history occurred when in 1949 Aldo Leopold announced the concept of a land ethic: We are all part of the greater interconnected whole of plants, animals and microorganisms. Out of this pronouncement was born the new science of environmental studies. Since then, great strides have been made in understanding the web of life, and our dependence on the health of the environment we live in. Core Biology: Environmental Sciences is the story of the creation of this new biological discipline, which includes the study of ecosystems and the blossoming of the environmental system.