Robert Berner is a well-regarded American geologist and academic. He was born in 1935 in Pennsylvania and was a professor in the department of Geology and Geophysics at Yale University from 1965 until his retirement in 2007. His most famous work focused on sedimentary rocks and the carbon cycle (the natural flow of carbon atoms through organisms and the environment/atmosphere). He and other colleagues developed the BLAG model of the carbon cycle in 1983 (the "B" stands for Berner). Using this model, they developed models for prehistoric climate and atmospheric carbon dioxide taking into account that carbon from decaying organisms eventually becomes chemicals in sedimentary rocks as well as atmospheric carbon dioxide. The carbon in these rocks and the atmosphere also makes its way back into biomolecules in plants and then animals, thus becoming a part of the carbon cycle.