During the 1920s and early 1930s, the AMNH sent teams of experts to the rich fossil outcrops of Mongolia and China in search of unknown chapters in prehistory. The naturalists found an abundance of wonderful fossil creatures, and among their discoveries were two quarries full of Platybelodon skeletons in China’s Tunggur Formation. Found in 1928 and excavated in 1930, the sites yielded a nearly complete growth series for this strange, elephantine beast, which paleontologists Henry Fairfield Osborn, Walter Granger, and Roy Chapman Andrews described in 1932.

At first, the strange anatomy of the animals from China seemed to most closely resemble that of an extinct proboscidean which had recently been found in the strata of Nebraska by Erwin Hinckly Barbour. Barbour