From: simon@dcs.warwick.ac.uk (Simon Clippingdale)
Subject: Re: Creationist CRAPOLA!
Organization: Department of Computer Science, Warwick University, England
Date: Sun, 27 Sep 1992 22:27:52 GMT

In article <19920924.141504.179@almaden.ibm.com> mannk@fshvmfk1.VNET.IBM.COM writes:
>
> What is there to explain?  Creations accept that what you term as
> micro-evolution occurs.
>
> What Creationists don't accept is the extrapolation that since
> micro-evolution has (and does) occurred, then certainly macro-evolution
> must have occurred.
>
> The first is observed and proven.  The second is speculated.
>
> Again, Creations do not accept that macro-evolution has occurred.
> People are still people.  Dogs are still dogs.  Fish are still fish.
> Etc.  One kind has not changed into another.
>
> Notice we still observe (present tense) micro-evolution.
>
> I ask again for observations of macro-evolution happening.


See my response to your other similar request, which I've posted under the
thread title "Response to Ken Mann", unsurprisingly.

See therein the comment from Michael White's _Modes of Speciation_ to the
effect that most genotypic differences between sibling species arise as
a result of *microevolution* subsequent to the speciation event. I note
that you accept that microevolution happens.

The reality you face is one in which microevolution happens, and in which
speciation is *observed* to happen also. Let's say that two populations of
species X become reproductively isolated [speciation] due to geographic
isolation (allopatry) or some other mechanism. I assume you have no
objection in principle to the realism of this proposition. They then go
their separate ways courtesy of microevolution. One species has become
two, but it isn't a case of a fish turning into a camel. It's a case of
a fish population turning into two non-interbreeding fish populations.
Then wait a few thousand years and you have two non-interbreeding fish
populations plus the accumulated effects of a few thousand years of
microevolution on each of them. It's the microevolution that drives
the two daughter species apart in terms of their characteristics.

There is no extrapolation involved in `going from microevolution to macro'.
Once you have microevolution, all you need is some mechanism which can
occasionally cause reproductive isolation and bang, you have a system
which can only result in a tree-structured ancestral and historic
relationship between species.

The proponent of such a mechanism as the cause of the observed biological
diversity could predict that if that model is correct, organisms should
exhibit a corresponding tree-structured hierarchical relationship of
traits, morphological, genetic and biochemical.

This is the basis of the theory of common descent, and such predictions
are repeatedly borne out in practical observations of the natural world.
While this does not rule out the possibility that other mechanisms are
also at work, it can only add to confidence that common descent is not
only feasible in principle (as I hope to have demonstrated) but is actually
what happened.


> Shalom!  |  INTERNET: mannk@fshvmfk1.vnet.ibm.com
>   Ken    |  VNET:     FSHVMFK1(MANNK)
>          |  IBMnet:   mannk@saskatchewan.fishkill.ibm.com
>-----------------------------------------------------------
>               You can only coast downhill!

Cheers

Simon
-- 
Simon Clippingdale                simon@dcs.warwick.ac.uk
Department of Computer Science    Tel (+44) 203 523296
University of Warwick             FAX (+44) 203 525714
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