posted on Jan, 9 2017 @ 02:34 AM
These ancestral DNA tests work by comparing a sample of your DNA against a pool of samples from all over the world. They then match your DNA to what
is found in samples from various regions, and thereby come up with your approximate genetic history. They are not perfect representations of your
ancestry.
So the further back in time you go, the less accurate the test becomes, as there are fewer samples to draw from.
By the way, anyone who thinks these tests lead back to a "common ancestor" only a few thousand years ago, please remember how these tests work and
that they have limitations dependant upon sample size. So if you go back far enough, they'll only be able to match your sample against a very limited
sample pool.