Melvin Ellis Calvin (April 8, 1911 – January 8, 1997) was an American chemist. He discovered the Calvin cycle (with Andrew Benson and James Bassham). He was awarded the 1961 Nobel Prize in Chemistry for this work. Calvin spent most of his five-decade career at the University of California, Berkeley.
Using the carbon-14 isotope as a tracer, Calvin and colleagues mapped the complete route that carbon travels through a plant during photosynthesis. It starts with its absorption as atmospheric carbon dioxide, and ends with its conversion into carbohydrates and other organic compounds.
They showed that sunlight acts on the chlorophyll in a plant to fuel the manufacture of organic compounds. Calvin was the sole recipient of the 1961 Nobel Prize for Chemistry. He wrote an autobiography three decades later titled Following the trail of light: a scientific odyssey.
During the 1950s he was among the first members of the Society for General Systems Research. In 1963 he was given the additional title of Professor of Molecular Biology.