Paleontological studies were a part of the United States Geological Survey's (USGS) mission from its creation in 1879. The act establishing the USGS declared that fossils collected by the Survey be deposited in the United States National Museum (USNM) when no longer needed for investigations. As a result, several USGS paleontologists were stationed at the USNM, as honorary curators, to study and care for the collections. The main purpose of early paleontological work at the USGS was the identification and correlation of geologic formations by their fossil remains to aid geologists in delineating formations and making geologic maps.
As a result of a reorganization of the Geologic Branch, USGS, in 1900 the Division of Paleontology was established, with Timothy William Stanton as Paleontologist in Charge. Its name was changed to the Section of Paleontology in 1902, Section of Paleontology and Stratigraphy in circa 1907, and Paleontology and Stratigraphy Branch (P&S Branch) in 1949. Stanton remained in charge of USGS paleontological work until 1932. Other section or branch chiefs have included John B. Reeside, Jr., 1932-1949; Preston E. Cloud, Jr., 1949-1959; Charles W. Merriam, 1959-1962; J. Thomas Dutro, Jr., 1962-1968; Norman F. Sohl, 1968-1973; Joseph E. Hazel, 1973-1978; William V. Sliter, 1978-1983; Michael E. Taylor, 1983-1985; and Richard Z. Poore, 1985- .