Simpson, George Gaylord (1902-1984), was an American paleontologist who helped advance the study of evolution. He led several expeditions that found numerous prehistoric animal fossils. His studies of these and other fossils led him to make refinements to the classification of animals and evolutionary theory.
In his book Tempo and Mode in Evolution (1944), Simpson argued that living things evolve (gradually change) in three ways. He labeled these ways speciation, phyletic evolution, and quantum evolution. In speciation, a group leaves the main population and gradually evolves into a new species. In phyletic evolution, an entire species slowly evolves into a new species. In quantum evolution, isolated members of a species evolve rapidly into a new species. Simpson’s ideas contributed to the development of the synthetic theory of evolution. This theory synthesizes (combines) evolution theory with genetics, paleontology, and other sciences.
Simpson was born in Chicago on June 16, 1902. In 1926, he received his doctoral degree from Yale University. Simpson served as curator of vertebrate fossils at the American Museum of Natural History. He was also a professor of paleontology at Harvard University. Simpson died on Oct. 6, 1984.
See also Evolution (History of the theory of evolution) .
