In 1891, Osborn was hired by Columbia University as a professor of zoology; simultaneously, he accepted a position at the American Museum of Natural History, New York, where he served as the curator of a newly formed Department of Vertebrate Paleontology. As a curator, he assembled a remarkable team of fossil hunters and preparators, including William King Gregory; Roy Chapman Andrews, a possible inspiration for the creation of the fictional archeologist Indiana Jones; and Charles R. Knight, who made murals of dinosaurs in their habitats and sculptures of the living creatures. On November 23, 1897 he was elected member of the Boone and Crockett Club, a wildlife conservation organization founded by Theodore Roosevelt and George Bird Grinnell. Thanks to his considerable family wealth and personal connections, he succeeded Morris K. Jesup as the president of the museum's Board of Trustees in 1908, serving until 1933, during which time he accumulated one of the finest fossil collections in the world. Additionally, Osborn served as President of the New York Zoological Society from 1909 to 1925.