We are living in an amazing age. DNA findings inform us that the first human beings are far older than we can imagine. The latest find is told by Colin Barras in “The father of all men is 340,000 years old” and in the American Journal of Human Genetics, doi.org/kp4. The story of this new marking of when the first humans began has been traced to the DNA of a man named Albert Perry.
As Barras relates it, the story begins:
“Perry, recently deceased, was an African-American who lived in South Carolina. A few years ago, one of his female relatives submitted a sample of his DNA to a company called Family Tree DNA for genealogical analysis.
“Geneticists can use such samples to work out how we are related to one another. Hundreds of thousands of people have now had their DNA tested. The data from these tests had shown that all men gained their Y chromosome from a common male ancestor. This genetic "Adam" lived between 60,000 and 140,000 years ago.
“All men except Perry, that is. When Family Tree DNA's technicians tried to place Perry on the Y-chromosome family tree, they just couldn't. His Y chromosome was like no other so far analysed.
“Deeper roots
“Michael Hammer, a geneticist at the University of Arizona in Tucson, heard about Perry's unusual Y chromosome and did some further testing. His team's research revealed something extraordinary: Perry did not descend from the genetic Adam. In fact, his Y chromosome was so distinct that his male lineage probably separated from all others about 338,000 years ago.
" ‘The Y-chromosome tree is much older than we thought,’ says Chris Tyler-Smith at the Wellcome Trust Sanger Institute in Hinxton, UK, who was not involved in the study. He says further work will be needed to confirm exactly how much older.”
The geneticist scholars say: “One possible explanation is that hundreds of thousands of years ago, modern and archaic humans in central Africa interbred, adding to known examples of interbreeding – with Neanderthals in the Middle East, and with the enigmatic Denisovans somewhere in southeast Asia.”
The Biblical story of Adam and Eve has a new twist, one learned by DNA. How long will it take for religious people to adjust their account of the origins of humankind to the findings of evolution is yet to be learned.
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