Calvin, Melvin (1863-1933), an American chemist, pioneered an interdisciplinary approach to problems in chemistry, biology, and physics.

In the 1950's, he devised an innovative method to determine how carbon dioxide is assimilated in green plants during photosynthesis. He identified the entire course of intermediary reactions in photosynthesis now known as the “Calvin cycle.” For this work, he won the 1961 Nobel Prize in chemistry.

Calvin's parents, Elias and Rose, emigrated from Russia to the United States in the 1880's. Calvin's father, though apparently well educated, became a factory worker, but he valued intellectual development. The family moved from Minnesota to Detroit, Michigan, when Calvin was young so that his father could work in an automobile plant.

Calvin attended public schools and graduated from high school in 1927. His schooling had little lasting impression on him. One of his few recollections was a physics teacher who declared that Calvin had no future as a scientist because he didn't collect all the data before solving a problem. Years later, Calvin addressed this very issue in his autobiography, Following the Trail of Light: A Scientific Odyssey (1992): “The synthesis of a really new concept requires some sort of union in one mind of the pertinent aspects of several disciplines…. It's no trick to get the right answer when you have all the data. The real creative trick is to get the right answer when you have only half of the data in hand and half of it is wrong and you don't know which half is wrong. When you get the right answer under these circumstances, you are doing something creative.”

By the time Calvin started high school, he had decided to pursue a career in chemistry. In 1927, he entered the Michigan College of Mining and Technology (now Michigan Technological University) in Houghton on a full scholarship. But two years later, the Great Depression hit. Calvin's father lost his job, and Calvin left school to work and help support the family. He soon resumed his studies and, in 1931, earned a B.S. degree. He attended graduate school at the University of Minnesota, where he investigated research problems in both physical and organic chemistry.

In 1935, he obtained a Ph.D. degree after completing a dissertation on the electron affinity of iodine and bromine. After receiving a Rockefeller Foundation fellowship, he spent two years doing postdoctoral work at the University of Manchester, England, with Professor of Physical Chemistry Michael Polanyi.

Calvin returned to the United States in 1937 and was appointed an instructor in chemistry at the University of California at Berkeley. His early research there focused on investigating the relationship of electronic structure to the color of organic compounds. He then turned his attention to physical organic chemistry. The resulting book, The Theory of Organic Chemistry (1941), co-written with Gerald E. K. Branch, is considered to have significantly influenced modern theory. In 1941, shortly before the United States entered World War II (1939-1945), Calvin was named assistant professor at Berkeley. In 1942, Calvin married Marie Genevieve Jemtegaard, a social worker. The couple had two daughters and one son.

Although Calvin continued to teach during the war, he became active in the national war effort. He was an investigator for the National Defense Research Council from 1941 to 1944 and a researcher for the Manhattan Project from 1944 to 1945. To aid the war effort, Calvin developed a simple method to obtain pure oxygen from the atmosphere for use in industrial applications, including welding. This process proved important in regions such as the South Pacific, where regular supplies of oxygen were not available.

When the war ended, Calvin returned to Berkeley. He was appointed associate professor of chemistry at Berkeley in 1945 and two years later, promoted to full professor. He remained there until he retired.

In the fall of 1945, Ernest Orlando Lawrence, director of the Radiation Laboratory at Berkeley, advised Calvin that “now is the time to do something useful with radioactive carbon,” or carbon 14, which had been discovered at the laboratory five years earlier. In February 1946, Calvin proposed a project studying photosynthesis, an investigation incorporating carbon 14. To accomplish this task, he organized the Bio-Organic Chemistry Group, which included biologists, chemists, and physicists. Team members worked in an atmosphere of cooperation and open communication. A member commented, “It was a remarkably harmonious organization: Calvin's scientific leadership, Ernest Lawrence's stewardship, the quality of the scientists, the excitement of the project, adequate funding—all were significant factors contributing to success.” For his part, Calvin, who had a limited background in biology, began studying the biological sciences in the mid-1940's and continued his studies until the late 1950's.

Calvin hoped to shed light on photosynthesis, a process that scientists did not totally understand. Joseph Priestley had discovered the basic principle of photosynthesis—that plants use the energy from sunlight to transform carbon dioxide and water into carbohydrates and oxygen—in 1772. By the 1940's, scientists knew the conditions necessary for photosynthesis to take place and the products that resulted from it, but the intermediate reactions in the process were largely unknown.

Calvin devised an ingeniously easy way to find out. The green alga chlorella was grown in a round, flat, water-filled “lollipop flask” exposed to light. Calvin introduced carbon dioxide containing carbon 14 into the flask. As the chlorella carried out its life processes, it took in the radioactive carbon 14 and incorporated it into the carbohydrates it produced. The isotope acted as a tracer, enabling Calvin to map the path of the carbon throughout the process. Along the way, Calvin collected and analyzed plant extractions. Although the premise of the research was simple, the analytical tools he used were advanced and included paper chromatography and radioautography. He spent 10 years accurately determining the reactions and compounds and identified 11 intermediate compounds in all.

After winning the Nobel Prize in 1961, Calvin used radioactive oxygen isotopes to trace the path of oxygen during photosynthesis. In 1963, Calvin was appointed professor of molecular biology. Eight years later, he was named university professor of chemistry. From 1960 to 1980, he served as director of the Laboratory of Chemical Biodynamics at Berkeley, a facility he established to research subjects such as solar energy conversion, brain chemistry, and the origin of life on earth. He oversaw construction of the laboratory building, which was built in a circle to promote the idea of an open laboratory. Following his retirement in 1980, the facility was renamed the Melvin Calvin Laboratory. In 1967, Calvin received a simultaneous appointment as associate director of the Lawrence Berkeley Laboratory.

In 1955, Calvin attended the International Conference on Peaceful Uses of Atomic Energy in Geneva, Switzerland. He also served on committees regarding molecular biophysics, biochemistry, science and public policy, and he was an adviser to the National Aeronautics and Space Administration (NASA). Even after retirement, Calvin continued his research in areas such as chemical carcinogenesis and organic geochemistry. He wrote approximately 500 papers and articles and wrote or cowrote many books, including The Path of Carbon in Photosynthesis (1957).

In addition to receiving the Nobel Prize, Calvin was elected to the Royal Society (1959) and received the Davy Medal of the Royal Society of London (1964), the Priestly Medal of the American Chemical Society (1978), the Gold Medal of the American Institute of Chemists (1978), the Oesper Prize of the American Chemical Society (1978), and the National Medal of Science (1989). He held membership in a number of organizations, including the National Academy of Sciences, the American Academy of Arts and Sciences, and the American Philosophical Society. He served as an officer of the American Association for the Advancement of Science and was president of the American Chemical Society in 1971.

In his later years, Calvin explored alternative fuels and the biological basis for learning. The Calvins maintained a farm in northern California, where Calvin planted rubber trees to see if their sap could be used as a substitute for petroleum. In other investigations, he discovered organic substances within meteorites, which he believed showed that life might exist elsewhere in the solar system.