In Memoriam: Internationally Renowned Dinosaur Expert John H. Ostrom

Dr. John H. Ostrom, one of the most influential figures in 20th century dinosaur paleontology, died peacefully at The Sarah Pierce Assisted Living Community in Litchfield, CT, on July 16, 2005 of complications of Alzheimers Disease.

Ostrom was professor emeritus of geology and geophysics at Yale University and curator emeritus of paleontology at the Yale Peabody Museum of Natural History. He is best known for his extraordinary discovery in Montana in 1964 of Deinonychus, a small two-legged carnivorous dinosaur whose name means “terrible claw,” and for his controversial theory that Deinonychus may have been a warm-blooded dinosaur. This theory, published in 1969, contradicts the earlier belief held by scientists that all dinosaur species were cold-blooded.

Ostrom is also known for having reintroduced an idea first put forth a century ago that birds are the most logical descendents of the dinosaurs. His interest in the dinosaur-bird connection and the origin of flight started with his osteological study of what is now known as the Haarlem Archaeopteryx, the earliest known fossil bird. The specimen was discovered in 1885 but labeled Pterodactylus crassipes. In 1970 Ostrom correctly identified it as the fourth known specimen of Archaeopteryx.

Ostrom’s conclusions about Deinonychus were revolutionary. First, he presented Deinonychus as warm-blooded with a high metabolic rate. Furthermore, he argued that dinosaurs have more in common with big non-flying birds than with lizards. In 1973 he concluded that Deinonychus and other bipedal theropod dinosaurs, a group that includes Tyrannosaurus rex and Velociraptor, are the ancestors of all birds.

Although his theories were derided by fellow paleontologists, 30 years later the discovery of feathered dinosaurs in China validated Ostrom’s findings. “I never expected to see anything like this in my lifetime,” he said. “I literally got weak in the knees when I first saw photos. The apparent covering on this dinosaur is unlike anything we have seen anywhere in the world before – quite different from modern feathers or hair, but also different from the skin of other dinosaurs.”

Born in 1928 in New York City and raised in Schenectady, New York, Ostrom was introduced to the science of paleontology as an undergraduate at Union College where he started his studies as a pre-med student. An elective in geology that he took as an upperclassman effectively changed his life. His fascination paleontology was so great that he extended his undergraduate career in order to fulfill the credits for his new major in geology, a field in which he excelled immediately.

He graduated from Union in 1951, and in 1960 received a Ph.D. in geology and vertebrate paleontology at Columbia University. He joined the Yale faculty in 1961 where he was professor of geology and geophysics and curator of vertebrate paleontology at the Yale Peabody Museum of Natural History until retiring in 1992. He was also an editor of the American Journal of Science and received numerous awards for his work, including the Alexander von Humboldt Medal from West Germany, a Guggenheim Fellowship, and the Hayden Memorial Geological Award of the Academy of Natural Sciences.

Dr. Ostrom presided over a 1999 symposium at Yale on theropod phylogeny and avian origins, which was held in his honor and demonstrated an indebtedness of the scientific community to his work and ideas. Similarly, Ostrom had a crucial influence on a generation of dinosaur paleontologists, including most notably, his former student Robert Bakker. Experts in his field credit him with the modern worldwide interest in dinosaurs and a scientific perspective that has forever changed the field of paleontology.

Dr. Ostrom was the husband of the late Nancy (Hartman) Ostrom, who died in 2003. He is survived by two daughters: Karen Ostrom of Goshen, CT, and Alicia Linstead of Larkspur, CA; and three grandchildren. He was the son of the late William and Norma (Beebe) Ostrom.

A private service will be held this weekend at the convenience of the family. A memorial service will held at Yale University during the upcoming academic year.