The invertebrate holdings at Yale University now in the Yale Peabody Museum’s Division of Invertebrate Zoology began to grow immediately with the arrival of Addison E. Verrill in 1864 as the University’s first Professor of Zoology. Named Curator of Zoology in 1866 at the newly founded Peabody Museum, his collecting and describing of local marine and freshwater fauna formed the basis of what was to evolve into a major collection of Western Atlantic coastal invertebrates for the Museum.
The study of Atlantic Coast invertebrates obtained through Verrill’s 16-year association with the U.S. Fish Commission (including examples of rare deepwater forms taken by the steamers Speedwell, Fish Hawk and Albatross) resulted in the discovery of many new species, some described by Verrill’s students and assistants: Oscar Harger (isopods); Katherine J. Bush (mollusks); and Verrill's brother-in-law and fellow Yale professor, Sidney I. Smith (crustaceans). Verrill and Smith’s Invertebrate Animals of Vineyard Sound (1873) remains an important reference manual of Atlantic Coast marine invertebrate fauna.
Verrill also actively secured material from various collectors (notably F.H. Bradley and J.A. McNiel), including corals, shells and echinoderms from the Gulf of California, Central and South America, and maintained exchange programs with Harvard University’s Museum of Comparative Zoology, the Smithsonian Institution, the Essex Institute, the Boston Society of Natural History, and other institutions. Both Verrill and Smith (who worked exclusively on crustaceans) described many new taxa from this exchanged material. Corals were of particular interest to Verrill; he published extensively on the Peabody specimens, including a review of coral type specimens originally described by James D. Dana from material collected by the United States Exploring Expedition (1836–1842).
A huge collection of invertebrates from expeditions to Bermuda in 1898 and 1901 formed the basis of many of Verrill’s articles and monographs. Other specialists enlisted to describe the Bermudan fauna included, among others, W.G. Van Name (tunicates), Harriet Richardson (isopods), Beverley W. Kunkel (amphipods) and Katherine Bush (polychaetes).
After Verrill’s retirement in 1910, the growth of the Museum’s invertebrate collections slowed considerably, although he continued to publish until his death in 1926.
Verrill’s student Wesley R. Coe, a nemertean specialist, followed Verrill as curator in 1911. Earlier, as a member of the Harriman Alaska Expedition (1899), Coe had obtained for Yale the nemerteans and tube dwelling polychaetes (sabellid and serpulid) that he and Katherine Bush described in important monographs.
Stanley C. Ball succeeded Coe as the Peabody’s Curator of Zoology, serving until 1954. In 1953, Willard D. Hartman began a nearly 40-year tenure as the Museum’s first Curator of Invertebrate Zoology, serving until his retirement in 1992. Under his stewardship the collections began to grow again, particularly in areas of his principle research interest, the systematics and evolution of sponges and their association with coral reefs. Hartman assembled a large series of invertebrates, primarily sponges and corals, from many Caribbean localities and was a participant in several expeditions to the tropics, notably to the Indian Ocean (Yale Seychelles Expedition, 1957–1958), Jamaica and Belize (NEKTON submersible dives, 1972), and the Philippines (ALPHA HELIX cruise, 1975). Many of Hartman’s students conducted research on sponges and corals, particularly from the Caribbean, and the Pacific coast of Panama, have resulted in large collections of these organisms at the Yale Peabody Museum.
In 1959 divisional holdings increased greatly with the incorporation of invertebrate specimens from Yale’s Bingham Oceanographic Collection.
In 1994, most of the zoological specimens of the George M. Gray Museum Collection were transferred to the Yale Peabody Museum and incorporated within the invertebrate zoology and vertebrate zoology (ichthyology) collections. This collection complements the Division’s holdings gathered by A.E. Verrill and his colleagues in the late 19th century.
In recent decades, the Division has continued to grow in areas that reflect the research interests of faculty, students and staff.
In 1992, Leo W. Buss became Senior Curator of Invertebrate Zoology. The research program of Professor Buss and his students investigate basic evolutionary questions, focusing on cnidarians (hydroids, jellyfish and others) and the simplest of all multicellular animals, the placozoan Trichoplax adhaerans. To this end, collections that provide new material for molecular studies now represent an area of rapid growth.