The date the first humans migrated from Africa has been pushed back 60,000 years by scientists. Researchers suggest that early humans began crossing to Eurasia as early as 120,000 years ago. The traditional ‘Out of Africa’ model suggests that modern humans evolved in Africa and then left in a single wave around 60,000 years ago.
But advances in DNA testing and other fossil analysis techniques show that humans actually arrived in Asia much earlier than previously thought, according to a review of recent research.
The study also claims migrants dispersed across Eurasia in a number of waves across tens of thousands of years, interbreeding with their human-like cousins along the way.
The researchers, from the Max Planck Institute for the Science of Human History in Jena, Germany, reviewed research on early human migration spanning the past decade.
Recent findings show that the ‘Out of Africa’ theory does not tell the full story of our ancestors, the study found.
Instead, multiple, smaller movements of humans out of Africa beginning 120,000 years ago were then followed by a major migration 60,000 years ago.
Most of our DNA is made up of this latter group, but the earlier migrations, also known as ‘dispersals’, are still evident.
This explains recent studies finding that all modern non-African populations branched off from a single group in Africa around 60,000 years ago.
‘The initial dispersals out of Africa prior to 60,000 years ago were likely by small groups of foragers, and at least some of these early dispersals left low-level genetic traces in modern human populations,’ study coauthor Professor Michael Petraglia said.
The researchers, from the Max Planck Institute for the Science of Human History in Jena, Germany, reviewed research on early human migration spanning the past decade.
Recent findings show that the ‘Out of Africa’ theory does not tell the full story of our ancestors, the study found.
Instead, multiple, smaller movements of humans out of Africa beginning 120,000 years ago were then followed by a major migration 60,000 years ago.
Most of our DNA is made up of this latter group, but the earlier migrations, also known as ‘dispersals’, are still evident.
This explains recent studies finding that all modern non-African populations branched off from a single group in Africa around 60,000 years ago.
‘The initial dispersals out of Africa prior to 60,000 years ago were likely by small groups of foragers, and at least some of these early dispersals left low-level genetic traces in modern human populations,’ study coauthor Professor Michael Petraglia said.
Over the past decade, early human remains have been found in the far reaches of Asia dating back further than 60,000 years.
For example, H. sapiens remains have been found at multiple sites in southern and central China that have been dated to between 70,000 and 120,000 years ago.
Other recent finds show that modern humans reached Southeast Asia and Australia prior to 60,000 years ago.
Based on these studies, humans could not have come in a single wave from Africa around this time, the study found.
After leaving Africa, our ancestors interbred with other hominins already present in Asia, such as Neanderthals and Denisovans, the researchers said.
Recent research estimates that all present-day non-Africans have 1-4 per cent Neanderthal heritage.
Another group suggested that modern Melanesians have an average of 5 per cent Denisovan heritage.
Based on this recent research, Neanderthals, Denisovans and perhaps other hominin groups likely overlapped in time and space in Asia, and had many instances of interaction, the Max Planck study claimed.
The authors argued for the development of more complicated models of human dispersals from Africa.
They said new research must be carried out in the areas of Asia where none has been done to date.
‘Fortunately, there have been an increasing number of multidisciplinary research programs launched in Asia over the past few decades,’ study coauthor Dr Katerina Douka said.
‘The information that is being reported is helping to fill in the gaps in the evolutionary records.’
Daily Mail
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