Announcement
Collapse
No announcement yet.
DNA Evidence Supports Three Land-Bridge Migrations
Collapse
X
-
I found it interesting that some Siberian groups carry "First American" DNA, establishing migrants back to Asia. I also wonder if 15,000 years ago is the earliest the genetic evidence allows and if studies like this invalidate very early dates from some South American sites??
Rhode Island
Comment
-
Using modern DNA to predict the past can be very complicated, misleading and just plain wrong. It all depends on how early or recent the events and people happened that you want to use modern DNA to talk about.
Modern DNA could be used to predict past events that only happened around 10,000 years ago and would probably be reasonably accurate.
However if you want to use modern DNA to make predictions about past events that happened 30,000 years ago or earlier then it would fail most of the time to be an accurate predictor.
This is because over a really long time span it is extremely likely that a lot of original DNA was lost from groups as fresh DNA was added to the groups as periodically.
What this means is that one group may have joined another group and there would have a reshuffling of DNAs. If an early group was involved in constant warfare and was overrun by a larger one this would have been the case.
If they were all killed their DNA would simply disappear from the genetic record altogether. The same thing would happen if the winning group allowed some of the defeated survivors to join their group.
Over 20,000 years or so, the DNA of the adopted ones would also disappear from the larger group.
The DNA of smaller or even larger groups who may have begun a culture or at least played a major role in shaping events would be lost or replaced altogether.
This is why I believe the only DNA that may be used to accurately predict the distant past is the DNA from that distant past.
Comment
Comment