Re: Date for Last Common Ancestor?

Susan S. Chin (
Thu, 15 Aug 1996 02:13:16 GMT

Stephen Barnard ( wrote:
: Susan S. Chin wrote:
: >
: > The problem I see with this argument is that evolution occurs in nature,
: > not in a mathematical equation (or whatever that was). As such,
: > hierarchies exist, meaning differing levels of organization produce
: > elements that can't possibly be accounted for by simple equations. It'd
: > be nice (no, it wouldn't actually) if things were as simple as you've
: > made it out. But I seriously doubt that they ever are in nature.
: >

: The only fact of nature that this argument relies on is that no one has
: more than one mother. I suppose there are other hidden assumptions,
: such as that all inheritance comes from one's parents, and not from (for
: example) gene transfer via viruses. Otherwise, it's just an exercise in
: logic. There may be an error in the logic, because I'm far from
: infallible, but you haven't pointed it out. You merely questioned my
: motives in another post.

: Mathematics isn't a useless frippery. It allows us to draw conclusions
: from assumptions. If the assumptions are true and the logic is correct
: then the conclusions are correct.

: Steve Barnard

As you've said, I'm not questioning your logic. What I do question though
is that the only "fact of nature used is that everyone has only one
mother," and whether such an exercise in logic proves anything at all.
What I see that it does "prove," if there are no logical flaws, is that
it is logistically possible that we all descended from a sole ancestor
popularly known as mitochondrial Eve. If that was your goal, and assuming
your argument is logically correct, then you would have accomplished it.