via the Levantine corridor and Horn of Africa to Eurasia. This migration has been proposed as being related to the operation of the Saharan pump, around 1.9 million years ago. Homo erectus dispersed throughout most of the Old World, reaching as far as Southeast Asia. Its distribution is traced by the Oldowan lithic industry, by 1.3 million years ago extending as far north as the 40th parallel (Xiaochangliang). Key sites for this early migration out of Africa are Riwat in Pakistan (~2 Ma?), Ubeidiya in the Levant (1.5 Ma) and Dmanisi in the Caucasus (1.81 ± 0.03 Ma, p=0.05). China shows evidence of Erectus from 2.12 Mya in Gongwangling in Lantian county. Two Homo erectus incisors have been found near Yuanmou, south China, and are dated to 1.7 Mya, and a cranium from Lantian has been dated to 1.63 Ma. Artefacts from Majuangou III and Shangshazui in the Nihewan basin, north China, have been dated to 1.6–1.7 Ma. The archaeological site of Xihoudu () in Shanxi Province is the earliest recorded use of fire by Homo erectus, which is dated 1.27 million years ago. Southeast Asia (Java) was reached about 1.7 million years ago (Meganthropus). Western Europe was first populated around 1.2 million years ago (Atapuerca). Robert G. Bednarik has suggested that Homo erectus may have built rafts and sailed oceans, a theory that has raised some controversy. After H. erectus One million years after its dispersal, H. erectus was diverging into new species. H. erectus is a chronospecies and was never extinct, so its "late survival" is a matter of taxonomic convention. Late forms of H. erectus are thought to have survived until after about 0.5 million ago to 143,000 years ago at the latest, with derived forms classified as H. antecessor in Europe around 800,000 years ago and H. heidelbergensis in Africa around 600,000 years ago. H. heidelbergensis in its turn spread across East Africa (H. rhodesiensis) and to Eurasia, where it gave rise to Neanderthals and Denisovans. H. heidelbergensis, Neanderthals and Denisovans expanded north beyond the 50th parallel (Eartham Pit, Boxgrove 500kya, Swanscombe Heritage Park 400kya, Denisova Cave 50 kya). It has been suggested that late Neanderthals may even have reached the boundary of the Arctic, by c. 32,000 years ago, when they were being displaced from their earlier habitats by H. sapiens, based on 2011 excavations at the site of Byzovaya in the Urals (Komi Republic,