According to current theory (e.g. Leakey) Homo erectus emerged in Africa some 1.7 million years ago. By 1 million years ago he was the only Hominid species on earth. It was Homo erectus who modern archaeologists claim first migrated out of Africa and support for this theory comes from fossil and tool evidence in Georgia, Java and China. From this initial migration, many claim, the Neanderthals developed. Consensus places their lifespan as a species from 230,000 to 35,000 years B.P. However rival theories compete as to the development of modern man.
Both camps (though not all Archaeologists) accept the initial migration out of Africa some 1 million years ago of Homo Erectus. However some argue that further migrations of anatomically modern humans (Homo Sapiens) occurred around 100,000 years ago and replaced all others stocks including the Neanderthals. This is the population replacement model as against the regional continuity proposal which argues that modern humans evolved semi independently in parts of the world from various ancients .Thus Neanderthal in Europe, Homo erectus in China and Java. Did these people evolve into moderns or were they an evolutionary dead end, as population replacement would argue?