Adam and Eve lived in Africa at the same time - but probably
never met, scientists claim.
It was previously believed that ‘Y-chromosomal Adam’ and
‘Mitochondrial Eve’ - the most recent common ancestors to males and females -
lived at completely different times.
But a new study of 69 men from around the world found
‘Y-chromosomal Adam’ walked the Earth between 120,000 and 156,000 years ago,
much earlier than previously believed.
A new study of 69 men from around the world found
'Y-chromosomal Adam' walked the Earth between 120,000 and 156,000 years ago,
much earlier than previously believed. It places him nearer to Eve who was
around 99,000 to 148,000 years ago the analysis found
It places him nearer to Eve who was around 99,000 to 148,000
years ago the analysis found.
But the researchers say it is ‘extremely unlikely’ they were
exact contemporaries.
Initial estimates for the male MRCA ranged from between
50,000 to 115,000 years ago.
Geneticist Professor Carlos Bustamante, of Stanford
University, California, said: 'Previous research has indicated the male most
recent common ancestor (MRCA) lived much more recently than the female MRCA.
But now our research shows there is no discrepancy.'
Mitochondrial Eve and Y-chromosomal Adam are the two
individuals who passed down a portion of their genomes to the vast expanse of
humanity.
But many aspects of their existence, including when they
lived, are shrouded in mystery.
The researchers compared Y-chromosome variations among
participants from nine globally distinct areas, including some that have only
recently been available, such as Namibia, the Democratic Republic of Congo,
Gabon, Algeria, Pakistan, Cambodia, Siberia and Mexico.
But despite the Adam and Eve monikers, which evoke a single
couple whose children peopled the world, they were not the only man and woman
alive at the time, or the only ones to have present day descendants.
They simply had the good fortune to successfully pass on the
Y chromosome and the mitochondrial genome across thousands of years to most of
us.
Powerful, state of the art microscopes allowed the
identification of about 11,000 mutations, enabling the researchers to establish
genetic links and timelines with unprecedented accuracy.
The study obtained results for 10 million nucleotides,
biological molecules that form the building blocks of the Y chromosome, for
each individual.
The annual mutation rate was then estimated by comparing it
with a known event, the human settlement of the Americas about 15,000 years
ago.
They repeated the analysis with the individuals’
mitochondrial DNA to generate the two estimates for Adam and Eve, showing for
the first time they overlap.
Professor Bustamante said: ‘We can now date certain events
very precisely. We found a single variant that shows how three ancient lineages
came together about 48,000 years ago, plus or minus only a couple of hundred
years. The accuracy is exquisite.’
The tree, published in Science, also exemplifies the
extraordinary depth of genetic diversity present among modern Africans.
But it is also possible it represents a time when only a few
sequences were passed on and many died out due to an external event that has
not yet been identified.
‘For the most part, it is a random process. Some lineages
die out, some are successful,’ said David Poznik, a graduate student in Prof
Bustamante’s lab.
‘But it is also possible there may be elements of human
demographic history that predispose these lineages to coalesce at certain
times.’
Report on research is done by Daily mail Uk
Interesting.civilisation actually started in Africa.unfortunately they so backward in their thinking. I wonder what went wrong and when.We still live in abject poverty being driven up and down like slaves by a sect that came after us.even adam will shake his head for us in his grave. What a shame
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