out of Africa. These dates could therefore mean that humans spread rather rapidly across the Old World, over a period of less than 70,000 years. Yuanmou Man could also indicate humans dispersed from south to north across China, but there are too few other well-constrained early Chinese sites to test this hypothesis. Humans likely already settled in China at earliest 2.12 million years ago evidenced by stone tools recovered from the Loess Plateau in northwestern China. Classification The teeth were formally described in 1973 by Chinese palaeoanthropologist Hu Chengzhi, who identified it as a new subspecies of Homo erectus, distinct from and much more archaic than the Middle Pleistocene Peking Man, H. ("Sinanthropus") e. pekinensis, from Beijing. He named it H. ("S.") e. yuanmouensis, and believed it represents an early stage in the evolution of Chinese H. erectus. In 1985, Chinese palaeoanthropologist Wu Rukang said that few authors in the field recognise H. e. yuanmouensis as valid, with most favouring there having been only one subspecies of H. erectus which inhabited China. However, in 2011, Indonesian palaeoanthropologist Yahdi Zaim and colleagues, based on dental comparisons, concluded that the Sangiran H. erectus—which had colonised Java by 1.6 million years ago—had descended from a different dispersal event than the Peking Man who had colonised China by 780,000 years ago. The Sangiran teeth were notably more reminiscent of the early H. habilis from Africa than those of the Peking Man. This would mean that H. erectus dispersed across East Asia multiple times. Anatomy For the teeth, only the left and right first incisors are preserved for the Yuanmou Man. The left incisor measures in breadth and in width, and the right incisor and . The incisors are overall robust. They notably flare out in breadth from bottom to top. The labial (lip) side is mostly flat with the exception of some grooves and depressions, and the base is somewhat convex like that of the Peking Man. The lingual (tongue) side caves in like that of the Peking Man, but has a defined ridge running down the middle like H. (e?) ergaster and H. habilis. The cross section at the neck of the tooth (at the gum line) is nearly elliptical. Similar anatomy is also exhibited in Late Pleistocene archaic human specimens from Xujiayao, China; and Neanderthals from Krapina, Croatia. The tibia is a long mid-shaft fragment. It is gracile and laterally (on the