The collection documents the history of the Yale Peabody Museum, its exhibitions, and staff. The central photograph file in the Museum’s Archives division contains a representative record of exhibitions, exhibit preparation, publicity, selected specimens, research, staff, and events between 1960 and about 2000, as well as earlier documentation of specimens, exhibitions, research, and expeditions (many relating to paleontologist O.C. Marsh). The illustrations published in the Museum’s former membership publication, Discovery magazine (1965–1995), are on file.

Of particular interest among the holdings are O.C. Marsh-related subjects; old exhibits (e.g., the long-gone Foucault Pendulum); unique specimens (such as the first “Brontosaurus”); the Museum’s dioramas; Rudolph Zallinger painting the murals The Age of Reptiles and The Age of Mammals; the geology of Connecticut; and a collection of 35mm slides (approx. 50,000) of wildlife, especially birds and fish, donated for educational use).