Out of Africa
Out of Africa is about the recent African origin of modern humans. Since the 1980s this has been supported by a study of present-day mitochondrial DNA, and other sequence analysis. There is also evidence based on the physical anthropology of archaic fossil remains. The idea is very well supported. There are differing theories on whether there was a single exodus or several. A growing number of researchers also suspect that "long-neglected North Africa" was the original home of the modern humans who first trekked out of the continent.
The first truly modern humans seem to have appeared between 200,000 and 130,000 years ago. These early humans later moved out from Africa. By about 90,000 years ago they had moved into Eurasia. This was the area where earlier species of humans, (such as Neanderthals, Homo neanderthalensis) had been living for a long time (at least 500,000 years in western Europe).
By about 42 to 44,000 years ago Homo sapiens had reached western Europe, including Britain. In Europe and western Asia, Homo sapiens replaced the Neanderthals by about 35,000 years ago. The details of this event are not known. At roughly the same time Homo sapiens arrived in Australia. Their arrival in the Americas was much later, about 15,000 years ago. All these earlier groups of modern man were hunter-gatherers.
Genetic studies and fossil evidence show that archaic Homo sapiens evolved to anatomically modern humans solely in Africa between 200,000 and 60,000 years ago. Members of one branch of Homo sapiens left Africa at some point between 125,000 and 60,000 years ago, and that over time these humans replaced earlier populations of the genus Homo such as Neanderthals and Homo erectus.
The date of the earliest successful "out of Africa" migration (earliest migrants with living descendants) has generally been placed at 60,000 years ago based on genetics, but migration out of the continent may have taken place as early as 125,000 years ago according to Arabian archaeological finds of tools in the region.
References[change | change source]
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Currently available genetic and archaeological evidence is supportive of a recent single origin of modern humans in East Africa. However, this is where the consensus on human settlement history ends, and considerable uncertainty clouds any more detailed aspect of human colonization history.
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