On Thu, Feb 03, 2005 at 11:46:03PM -0800, DJA wrote:
Remember, in many cases, a birth defect is nature's attempt to adapt to a changing environment. It usually takes many, many failures before the adaptation is successful. That's just basic biology. Attempting to prevent all genetic "defects" is tantamount to taking away nature's ability to learn from its mistakes. Not only can we *not* prevent all birth defects, we should *not* do so.
OK, I was really enjoying what I saw as a _great_ reply when I his this bit of teleology. DJA, I _know_ you know this ... it is Very Bad Evolutionary Theory to characterize mutations as "nature's attempts" at anything. The theory rests on the assumption that there is no guiding force (although there could well have been a prime mover -- no opinion up or down there), but only the maelstrom of natural selection.
Well okay, we can argue all day about causal philosophies, the net effect is nevertheless the same. My anthropomorphism of nature (i.e. Nature) can be quite easily left out without damaging the premise of my statements. I agree that the theory is agnostic on the subject of intelligent direction (which I'll admit is counter to my beliefs, and so colors my arguments - my philosophy is as accurate as anyone else's after all).
Nevertheless, removing the organism's ability to adapt to environmental changes, or even to continue to select in favor of current conditions is eventually going to be fatal.
In other words, all mutations are blind chance, but those that don't survive and reproduce won't be around for long.
Well, that's the point then isn't it. We're assuming mutations won't be artificially selected out through gene manipulation.
The greatest birth defect is a miscarriage (or it's egg equivalent), and as much as they've been selected against (anyone on this list have a miscarriage as an ancestor? Thought not), they still happen with a fairly high frequency.
Again Biology 101. A miscarriage is not a birth defect but rather a response to a catastrophic birth defect which would otherwise lead to the probable non-viability of the the fetus.
--
Best Regards,
~DJA.-- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
