C'mon, Mike - you have been here a long time, and you've been told many times that "proof" is not a scientific term. "The preponderance of evidence shows X to be the best current explanation for Y" is how science phrases "proof."
Now a true extrapolation, logically, of a blind "fact", is that it is a fact I have a great grandfather or I wouldn't exist.
You don't
know that to be a fact. We've all heard of virgin birth, right? And though it's rather improbable among humans, it is concievable (phew! I had to type that....) that your grandfather was the product of one. It's on the same order of likelihood that the evidence of ERV's
don't point to common ancestry......
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