Here’s a recent news report on a search by scientists for the origin of the Y-chromosome. One groups of scientists places this starting point about 338,000 years ago. In the same news report, some other scientists argue for the more common opinion about the start of the human race about 200,000 years ago.
The search is portrayed by the media as a hunt for “the genetic Adam”. Of course, neither scientists nor news commentators see this as a search for the time when Adam and Eve lived. But it is nevertheless a hunt for the starting point of the human race. Y-chromosomes are handed down from father to son without any changes to the dna sequence, except the changes that occur by random mutation, slowly over many thousands of years.
There is also a type of hunt for “the genetic Eve”. Mitochondrial dna is handed down from mother to daughter (and son). Again, no changes occur in the dna sequence, except by slow random mutation over a very long time. This search, too, would postulate a starting point for the human race.
However, anthropologists distinguish between behaviorally-modern humans and anatomically-modern humans. The former have the capacity to reason abstractly; the latter are almost the same as modern humans in body, but they cannot reason abstractly. All human persons today are behaviorally-modern humans. But anthropologists generally believe that behaviorally-modern humans began only 50 to 70 ka (thousand years ago), while anatomically-modern humans began about 200 ka.
My theological opinion is that Adam and Eve were created miraculously by God, in the Garden of Eden (not on earth). Their bodies were patterned after the highest life form on earth at the time: anatomically-modern humans. As a result, we have dna in common with anatomically-modern humans and with the lower animals from which they evolved.
This idea implies that the Y-chromosome pre-dates Adam and pre-dates behaviorally-modern humans. It might also pre-date anatomically-modern humans, as one set of researchers claimed. The lower primates, from whom anatomically-modern humans evolved, also have Y-chromosomes. The dna of these primates is not so different from human dna; only a small percentage of the dna is different. So the dna of an ancient primate Y-chromosome might be very similar to a modern-day human Y-chromosome, without any implications as to when the human race began.
The hunt for a genetic Eve follows a similar line of reasoning. Mitochondrial dna pre-dates Eve, pre-dates behaviorally-modern humans, and pre-dates anatomically-modern humans. If God created Eve miraculously, as I believe, using the pattern of anatomically-modern humans, then her mitochondrial dna would be similar to theirs and to the mitochondrial dna of the lower animals. Finding that similarity in a species hundreds of thousands of years ago does not indicate the start of the human race.
Neither does the dating of this 300 ka cooking hearth. The fact that our pre-human ancestors could use fire to cook food does not imply that they possessed the abstract reasoning of behaviorally-modern humans. In other words, it does not imply the God-given gifts of reason, free will, and an immortal soul. Our pre-human ancestors may have used fire. But Adam and Eve came along at a much later date, perhaps about 50,000 years ago — not 200 thousand years ago, not 2 million years ago.
See my previous posts:
Evolution’s Glass Ceiling
Adam and Eve versus Evolution
Reconciling Adam and Eve with Evolution
Are we required by faith to believe that Adam and Eve were two real historical persons?