Quote Originally Posted by Sketraw View Post
...Don't get me wrong, DNA for sure has its place as it can prove in history who they were not perhaps, but more difficult to to prove whom they were descended from without the ancient DNA, yes it can prove a link but very difficult to fix it in a particular time line.

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Not at all.

See the FAQ at www.familytreedna.com

Y DNA mutates at a predictably consistant rate. By comparing Y DNA from 2 (or more) living men, a fairly accurate prediction can be made as to when their most recent common ancestor lived.

Further, genetic genealogists are able to identify with increasing precision, as more and more men are tested, the geographic location of their most recent common ancestor.