RE: [asa] Re: Reading Genesis theologically NOT historically

John:

What you seem to be saying is that there is "really" no distinction between what is called micro-evolution and macro.

I had thought that in micro evolution we have an established gene pool from which environmental factors could select or favor some.

Whereas, in macro-evolution we need be speaking of some notion of new genes, ones that were not previously in the population, but, nonetheless, might be able to mate with those lacking the new genes.

This distinction appears to make some sense to me and would, at least conceptually, permit the recognition of a new species, i.e., when a certain set of novel genes were in place.

But as I've said before I don't really understand how genes are capable of determining what an adult looks like. If genes are merely segments of DNA, then it doesn't appear sufficiently equipped to establish the development or character of an individual.

bill

On Tue, 6 Oct 2009 10:01:33 -0500, "Jon Tandy" <tandyland@earthlink.net> wrote:
> Cameron,
>
>
>
> Just a question about the okapi example. What if the offspring of the
> five-foot animal was not five foot six (presumably an unlikely event), but
> five foot plus half a centimeter, with the extra half centimeter being in
> the length of its neck. What if three generations down the line, there
> was a descendent who was five foot plus a full centimeter. Offspring for
> several generations might have been similar, within a degree of normal
> variability. What if ten generations later one of the offspring of one of
> those lines had a neck that was another half centimeter longer, while many
> of its cousins had been killed off through various environmental events.
> And so on, until there was a population, maybe 1000 generations later,
> whose survival had preserved the longer-neck genes and became what we call
> the giraffe.
>
>
>
> At what point in this sequence would you identify the first *giraffe*
> ancestor? Which half centimeter (or quarter centimeter, to make the
> challenge more difficult) increase in which lineage would classify as
> being the first? Biologists would tell us that the *first individual* of
> the population is in most cases immaterial, that the migration of
> population and genetic traits over time are what's more important.
>
>
>
> I have no idea whether this is how it happened, and I suspect that
> biologists don't really *know* either, but infer something like the above
> from the gradual nature of the (incomplete) fossil record. It could have
> been entirely different, with one mutant having a half-foot longer neck
> and also happening to be the lucky survivor when most of his fellow
> population got killed, being the proud father of longer necked descendents
> to a new population. But unless one could find the complete fossil record
> of every generation before and after that individual (and be able to prove
> that the fossil record was unbroken), there would be no way to prove that
> there was a first distinctive individual. Am I wrong?
>
>
>
> Jon Tandy
>
>
>
> From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu] On
> Behalf Of Cameron Wybrow
> Sent: Tuesday, October 06, 2009 2:10 AM
> To: asa
> Subject: Re: [asa] Re: Reading Genesis theologically NOT historically
>
>

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Received on Tue Oct 6 12:29:14 2009