Dear friends:
Since my last post of the article link related to Adam
was late for his first date Eve, I've googled more about
related topics;from this following link, we see the
estimate age of the first Eve has been updated.
yet the margin for error is so big.
( we see the estimate is almost like speculations with such a gigantic margin of error)
With that kind of margin of the error, the first Adam surely would be able to meet
the first Eve. Besides, there are many variables that can affect the mutation rate of mtDNA, including even the possibility that mtDNA is not always inherited strictly through maternal lines.
Furthermore, the so called forerunner of human species Neanderthas couldn't contribute to the gene pool of any modern humans. Isn't that interesting?
... That was back in 1987. Since then, researchers have updated the estimate to 120,000 to 150,000 years ago. However, the margin for error for this estimate and the previous one are significant—when all of the variables are taken into account, the current range is more like 50,000 to 500,000.
Moreover, the researchers determined that the common ancestor to Neanderthals and modern Homo sapiens lived as long as 500,000 years ago, well before the most recent common mtDNA ancestor of modern humans. This suggests (though it does not prove) that Neanderthals went extinct without contributing to the gene pool of any modern humans….
Final note
There are many variables that can affect the mutation rate of mtDNA, including even the possibility that mtDNA is not always inherited strictly through maternal lines. In fact, recent studies show that paternal mtDNA can on rare occasions enter an egg during fertilization and alter the maternal mtDNA through recombination. Such recombination would drastically affect the mutation rate and throw off date estimates.
Not surprisingly, there is currently a heated debate over the value of "mitochondrial Eve"—especially between history-hunting geneticists and some fossil-finding paleoanthropologists...
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