Explores the interaction of the biosphere, geosphere, and atmosphere on Earth, with focus on biogeochemical cycles and the methods used to study them. Examination of conditions on early Earth and the changes brought by the introduction of life. Course Information: Prerequisite(s): CHEM 112 or CHEM 122 and CHEM 123; and CHEM 114 or CHEM 124 and CHEM 125; and EAES 230 or EAES 285 or EAES 111; or consent of the instructor. Recommended background: BIOS 100 or BIOS 101.