John Harold Ostrom (b. February 18, 1928, d. July 16, 2005) was born in New York, NY. He received his bachelor of science degree in geology and biology from Union College in Schenectady, NY, in 1951, when he was invited to Columbia University by George Gaylord Simpson and spent that summer as Simpson’s field assistant in the San Juan Basin of New Mexico. In 1960 he earned his doctorate in geology (vertebrate paleontology) from Columbia. Influenced by Edwin H. Colbert at the American Museum of Natural History, where he was a research assistant from 1951 through 1956, Ostrom’s dissertation (published as a Bulletin of the American Museum of Natural History in 1961) was a comparative functional morphological study of the cranial anatomy of hadrosaurs (duck-billed dinosaurs). Ostrom taught at Brooklyn College in New York City (1955–1956) and served as staff geologist with the New York State Geological Survey and the American Museum of Natural History before joining the faculty at Beloit College in Wisconsin (1956–1961).

In 1961 Ostrom came to Yale University as assistant professor in its Department of Geology and Geophysics, and assistant curator of vertebrate paleontology at Yale’s Peabody Museum of Natural History, becoming a full professor and curator in 1971. At the Peabody Ostrom’s curatorship included the extraordinary collection of horned dinosaurs that are the legacy of O.C. Marsh, Richard Swann Lull and John Bell Hatcher, and he published several important papers on this group. Functional morphology and dinosaurs were central to Ostrom’s research throughout his career, and his publications have been influential in redefining the paleobiology and paleoecology of several groups.

Ostrom’s field projects in the 1960s produced research that would change long-held concepts in paleontology. From 1962 to 1967 Ostrom’s expeditions to the Bighorn Basin of Wyoming and Montana resulted in the discovery and description of a new dinosaur fauna from a poorly represented geologic period, including his now well-known description of Deinonychus antirrhopus (Postilla 128, Bulletin 30, 35). This work, along with the work of Ostrom’s former student Robert Bakker, redefined commonly held ideas about dinosaur evolution — both in the academic community and in the public mind — from that of plodding, cold-blooded reptiles to the intelligent, agile and gregarious ancestors of modern birds. Ostrom’s critique of dinosaurs as indicators of paleoclimate (presented at the first North American Paleontological Convention in Chicago in 1969) and his 1970 reidentification of the Haarlem specimen of Archaeopteryx, in which he recognized osteological similarities to Deinonychus and other small theropods, led to a renaissance in the study of dinosaurs and the evolution of flight.

Ostrom served as acting director of the Yale Peabody Museum from 1975 to 1976, as president of the Society of Vertebrate Paleontology from 1969 to 1970, and as editor of the Society’s bulletin from 1963 to 1973. He was also editor of the American Journal of Science and the Yale Peabody Museum’s Postilla and Bulletin series. His many awards and honors included a John Simon Guggenheim fellowship (1966–1967), the Alexander von Humboldt Stiftung in Germany (1976–1977 and 1985), the prestigious Hayden Memorial Geological Award (1986) of the Academy of Natural Sciences of Philadelphia for outstanding contributions in research and education in paleontology, and the Yale Peabody Museum’s Addison Emery Verrill Medal (1999).

In 1999 Yale University presented an international symposium in Ostrom’s honor on the origin and early evolution of birds attended by over 400 paleontologists and others from around the world. The conference was held in conjunction with the special exhibition China’s Feathered Dinosaurs at the Yale Peabody Museum, which brought to the northeastern United States the first viewing of the spectacular 120-million-year-old fossils of feathered theropods discovered in the Yixian Formation of Liaoning Province. These finds constitute, according to Ostrom, “the biggest event in evolutionary science since Darwin put forth his theory,” and provide compelling evidence that birds evolved from dinosaurs, an idea that Ostrom reintroduced 40 years earlier.

Dr. John Ostrom was married to Nancy Hartman and had 2 children. Dr. Ostrom passed away in Litchfield, Connecticut, on July 16, 2005.