The oldest anatomically modern human (AMH) fossils date from up to 130,000 BP have been found in East and South Africa and from 90,000 BP in Israel, where thy overlap and may even predate Neanderthals.
DNA projections put AMH originals back further to 150,000 BP.
AMH differ anatomically from all previous hominid species with gracile bones, flatter faces, high foreheads and a rounder skull.
Homo sapiens probably had language, ritual and art from an early stage.
They developed an extensive range of stone tools and their pace of technological change seemed to increase after 40,000 BP, suggesting greater communication.
Their expansion across the world was equally impressive, reaching Australia by 55,000 BP and America .13,000 BP.
Their population levels soon outstripped those of all other primates. There are two different theories for this.
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The Candelabra and multi-region models
The candelabra model was predominant in the mid-20th century and involved human ancestors leaving Africa around 2 mya and then independently developing into the different looking Homo sapiens found in Africa, Europe, Asis and Australasia.
This was discredited by DNA studies which showed that modern humans are virtually genetically identical.
Multiregionalism suggets that modern humans evolved from regional Homo erectus populations but that they also shared exchanged genes with humans in other parts of the world through migration.
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Replacement and assimilation models
These theories suggest that all modern humans originated from a single small population in Africa.
The 'Noah's Ark' theory sees a complete and comparatively rapid replacement of all earlier species throughout the world by fully modern people.
As a result there is no genetic differences between modern peoples.
Assimilation theories broadly align with this interpretaion but allow for some interbreeding with other species during this process.
Genetic studies of ancient DNA had a massive impact on these theories.
Pioneering work into mitochondrial DNA(mDNA) found that the greatest genetic variation amongst modern humans is in Africa.
In other words, they have had more time to accumulate the mutations that signal differences between populations, which suggests that Homo sapiens have been evolving there longest.
Studies in mDNA also predict that all modern people share thier mDNA with one woman, the so-called African 'Eve' who lived c. 200,000 years ago.
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New discoveries and methods
New discoveries constantly lead to reappratsals of these theories.
For example, a discovery in 1998 from Lagar Velho of a Neaderthal child with **** sapiens traits from 24,500 BP reignited the debate about interbreeding.
The modern 3-4 year old had a modern jaw and teeth but the limbs were Neanderthal.
The burial was more typical of **** sapiens with ochre, rabbit and deer bones in the grave.
Conclusive evidence came with the mapping of the full Neanderthal genome on 2008 from samples taken from the Vindija Cave in Croatia and dated to 44,000 BP
1-4% of Neaderthal genes were shared with modern Eurasian populations but none with Africans.
There have been more modern problems with all models as well.
Multiregionalism has been portrayed as racist or nationalistic by it critics.
Out of Africa 2 has been called overly religious or politically correct.
No DNA research is accepted universally.
Small populations of related species appear to have interbred on several occasions, which currently is interpreted as support by both multiregional and assimilation theorists.
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