Gould, Stephen Jay, 1941–2002, American paleontologist and science writer, b. Queens, New York; grad. Antioch College (B.S., 1963), Columbia Univ. (Ph.D., 1967). With Niles Eldredge, Gould proposed (1972) the evolutionary theory of "punctuated equilibrium," which states that in geologic time and strata, the appearance of a new species occurs suddenly and without the continuous slow accretion of tiny variations, due to the nature of the evolutionary process and the relationship between the evolutionary and geologic timescales (see evolution); and that the new species then persists virtually unchanged in the fossil record for perhaps millions of years. The "missing links" in evolutionary development sought since the time of Charles Darwin are thus unlikely to be found. Elaboration of these concepts has led to extensive scientific debate. Gould addressed these and other aspects of evolutionary thought in his magnum opus, The Structure of Evolutionary Theory (2002). He began his lifelong teaching career at Harvard in 1967 and wrote many other books, including Ontogeny and Phylogeny (1977), The Mismeasure of Man (1981), Wonderful Life: The Burgess Shale and the Nature of History (1989), and the posthumously published The Hedgehog, the Fox, and the Magister's Pox (2003), as well as essay collections drawn from his popular articles in Natural History magazine. Gould was also an avid baseball fan; his Triumph and Tragedy in Mudville, an essay collection, was also published posthumously in 2003.