1905 Boas leaves his position at the Museum and begins teaching at Columbia University. One of his students is Margaret Mead, the scientist, explorer, writer, and teacher, who will work in the Department of Anthropology at the American Museum of Natural History from 1926 until her death in 1978. A pioneer, she brings the serious work of anthropology into the public consciousness.
1908 Museum President Morris K. Jesup dies. Henry Fairfield Osborn becomes President. Osborn is the first Museum president trained as a scientist.
1913 Carl Akeley, a pioneer in the creation of lifelike mammal dioramas, writes to Osborn offering to devote five years to the creation of an African Mammals Hall at the Museum. Osborn agrees.
Roy Chapman Andrews
1921 Roy Chapman Andrews leads the historic Central Asiatic Expedition through the Gobi of Mongolia, discovering some of the richest dinosaur fossil sites in the world. Andrews and his team work there until the border between China and Outer Mongolia closes in 1930.
1926 The Museum receives an extensive gift of mammals from the Indian subcontinent, the result of an expedition led by Arthur S. Vernay and Colonel J. C. Faunthorpe. Work soon begins on designing a fitting environment for these specimens, which will be mounted according to Akeleys technique and displayed in dioramas.
1930 The first major hall of mammal habitat dioramas, the South Asiatic Hall, opens, displaying Vernay and Faunthorpes gift of specimens.
1933 F. Trubee Davison becomes President of the Museum. A. Perry Osborn becomes Acting President from 19411946, after which Davison resumes his position.
The Hall of Ocean Life opens on the first floor. The hall is renovated in 1969 to include a 94-foot-long model of a blue whale suspended from the ceiling.
1935 Legendary dinosaur explorer Roy Chapman Andrews becomes Director of the Museum.
The Hayden Planetarium opens.
Akeley Hall of African Mammals
1936 Theodore Roosevelt Memorial Hall and Rotunda open.
The Akeley Hall of African Mammals opens under the direction of James L. Clark, the Museums Vice Director. Artists and scientists, led by Carl Akeley, had gone to Africa to sketch, photograph, collect, measure, and make molds of leaves, bark, moss, and other aspects of the terrain to make the dioramas as accurate as possible.
1951 Alexander M. White becomes President of the Museum.
1953 The Whitney Hall of Oceanic Birds is completed and dedicated on the second floor of the Whitney Wing.
1954 The Hall of Man and Nature opens on the first floor.
1958 The Hall of North American Mammals opens on the first floor.
The Hall of North American Forests opens on the first floor.