American Museum of Natural History Research Library
author: American Museum of Natural History

American Museum of Natural History. Hall of Primitive Mammals.; Hall of Primitive Mammals; Primitive Mammals
birth: 1994
death: present
Permanent exhibition. Opened June 1994. Located on Floor 4, Section 5. The Hall of Primitive Mammals at the American Museum of Natural History, one of two halls in the Lila Acheson Wallace Wing of Mammals and Their Extinct Relatives, traces the lower branches of the evolutionary tree of mammals, including monotremes, marsupials, sloths, and armadillos. The hall features Dimetrodon, glyptodonts, the saber-toothed cat, and Lestodon. The Mammal Island in the center highlights members from this most diverse group of vertebrates. (1). The scientific team of paleontology curators, supervisors, and preparators for the hall installation included Mark Norell, Lowell Dingus, Eugene S. Gaffney, Michael J. Novacek (2, 1995), Jeanne Kelly, Phil Fraley, and Steven Warsavage (3, 1995, p. 6-10.).
The Museum reimagined its fossil halls in the 1990s. Chronologically arranged exhibits were updated to reflect evolutionary relationships. The Halls of Saurischian and Ornithischian Dinosaurs, the Lila Acheson Wallace Wing of Mammals and Their Extinct Relatives, which includes the Hall of Primitive Mammals and the Paul and Irma Milstein Hall of Advanced Mammals, the Hall of Vertebrates Origins, and the Miriam and Ira D. Wallach Orientation Center were the result of this rearrangement in exhibition (4, 1994-96, p. 5).
The Hall of Primitive Mammals highlights the development of key mammalian physical features such as the synapsid opening in the skull, a large hole behind the eye socket for muscles that extend to the jaw, three middle ear bones, and the placenta. These traits correspond to eating, hearing, and reproduction, and each trait represents a change in an evolutionary branch. Animal groups represented in this hall include monotremes, multituberculates, triconodonts, edentates, and extinct relatives of mammals, such as the Dimetrodon and glyptodonts. Some living animals from these groups, such as the egg-laying mammal platypus, a monotreme, are referred to as “living fossils.” (1).