Stephen Jay Gould (born September 10, 1941, New York, New York, U.S.—died May 20, 2002, New York) was an American paleontologist, evolutionary biologist, and science writer.
Gould graduated from Antioch College in 1963 and received a Ph.D. in paleontology at Columbia University in 1967. He joined the faculty of Harvard University in 1967, becoming a full professor there in 1973. Gould’s own technical research focused on the evolution and speciation of West Indian land snails. With Niles Eldredge, he developed in 1972 the theory of punctuated equilibrium, a revision of Darwinian theory proposing that the creation of new species through evolutionary change occurs not at slow, constant rates over millions of years but rather in rapid bursts over periods as short as thousands of years, which are then followed by long periods of stability during which organisms undergo little further change. Gould’s theory was opposed by many, including American biologist Edward O. Wilson, who believed that evolution is essentially progressive, leading from the simple to the complex and from the worse-adapted to the better.
Gould also argued that population genetics is useful—indeed, all-important—for understanding relatively small-scale or short-term evolutionary changes but that it is incapable of yielding insight into large-scale or long-term ones, such as the Cambrian explosion. One must turn to paleontology in its own right to explain those changes, which might well involve extinctions brought about by extraterrestrial forces (e.g., comets) or new kinds of selection operating only at levels higher than the individual organism. As with Gould’s theory on evolutionary change, much of his later work drew criticism from other scientists.
Apart from his technical research, Gould became widely known as a writer, polemicist, and popularizer of evolutionary theory. In his books Ontogeny and Phylogeny (1977), The Mismeasure of Man (1981), Time’s Arrow, Time’s Cycle (1987), and Wonderful Life (1989), he traced the course and significance of various controversies in the history of evolutionary biology, intelligence testing, geology, and paleontology. From 1974 Gould regularly contributed essays to the periodical Natural History, and these were collected in several volumes, including Ever Since Darwin (1977), The Panda’s Thumb (1980), and Hen’s Teeth and Horse’s Toes (1983). In Rocks of Ages: Science and Religion in the Fullness of Life (1999), Gould, who was then president of the American Association for the Advancement of Science, rejected the work of individuals who tried to integrate science and religion. According to Gould, science and religion were never at war but should remain separate. Gould’s science writing is characterized by a graceful literary style and the ability to treat complex concepts with absolute clarity.