Received: by alpheratz.cpm.aca.mmu.ac.uk id AAA11158 (8.6.9/5.3[ref firstname.lastname@example.org] for cpm.aca.mmu.ac.uk from email@example.com); Fri, 17 Aug 2001 00:27:32 +0100 From: <firstname.lastname@example.org> To: email@example.com Date: Thu, 16 Aug 2001 18:31:44 -0500 Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7BIT Subject: Re: Callouses and Kings Message-ID: <3B7C1190.1390.4CB7AF@localhost> In-reply-to: <002b01c126a8$a087cc60$e524f4d8@teddace> X-mailer: Pegasus Mail for Win32 (v3.12c) Sender: firstname.lastname@example.org Precedence: bulk Reply-To: email@example.com
On 16 Aug 2001, at 16:10, Dace wrote:
> From: <firstname.lastname@example.org>
> > > MR offers a model of evolution that gives organisms an active role
> > > in shaping themselves. We know, for instance, that camels begin
> > > developing calluses on their kneepads when they're still in the
> > > womb. This would suggest that camels who developed calluses as a
> > > result of kneeling in the desert passed this trait onto their
> > > offspring. Since behavior can't directly affect genes, the
> > > logical assumption is that the calluses are passed on
> > > non-genetically. Otherwise we must accept the colossal
> > > improbability that the genetic mutation for calluses on the
> > > kneepads just happened to appear right when the camels needed it.
> > > You'd think they'd have to have gone through a lot of useless
> > > mutations first, like calluses in other places, or the wrong
> > > alterations on kneepads before they'd hit on the right mutation.
> > > How many millions of years should it have taken for them to get
> > > the right mutation? Now consider the fact that this applies many
> > > times over for every species on earth, and you start to see just
> > > how high that mountain of improbability is. Sheldrake offers a
> > > more streamlined, elegant model of evolution.
> > Callouses would not evolve all of a piece, but gradually;
> I can almost believe that with calluses, but the gradual emergence of
> complex structures like eyes is highly problematic. Most of what goes
> into an eye has no use unless the whole structure is present.
Not true; photosensitive patches, which do not register shapes, are
present in some microorganisms. Lenses could definitely evolve
gradually later, first as rough directional sensors, then more and
more fine-grained to illustrate configuration, then of course stereo
vision, which allows for depth perception, was most likely a lucky
thing in that multiple eyes most likely were selected for for the
same benefits found in many multiple systems; redundancy/ back
> > but what
> > you're REALLY missing here is dermatological understanding.
> > Animals (including us) can develop callouses anywhere there is
> > chafing on the skin; it's built into the dermis; the only
> > modification needed is one that permits such growth in the absence
> > of stimulation, and that mutation could happen anywhere, and only
> > stick where it was useful and selected for.
> You're simply restating the problem. If the mutation is random and
> could affect any part of the skin, why does it affect precisely the
> area where it's needed? And why not another mutation in that spot
I'm reasonably sure other mutations have happened within other
species, such as scales or chitinous shells, to handle similar
problems. I'm also sure that mutations happened to allow for
callous growth in other areas, but as they possessed no survival
value for the organism, they were not selected for.
> > There was a hundred
> > million years for camels and their precursors to produce such a
> > mutation - no problem.
> Mammalian evolution developed from primitive lemur-like stock very
> rapidly after the fall of the dinosaurs. Within a few million years
> all the basic forms were in place, from bats to whales.
Actually, um, no. Many mammals in their present configuration
are of more recent vintage, even though their precursors were not.
Bats and whales there may have been, but were they like the ones
around today? No. It might be instructive for you to peruse the
evolution of the eohippus into present-day horses (the Morgan
horse, for instance, developed out of a single dominant-trait mutant
within the last two hundred years) in order to realize that evolution
is a continuously ongoing process rather than something that
happens once a species and is then done.
> > Elegant explanations are not always
> > correct; otherwise we would embrace the elegant yet Occam-
> > violating explanation of a Master Designer intentionally sticking
> > those clumsy thumbs on pandas.
> To reject the Blind Designer is not necessarily to accept the Master
> Designer. I reject all concepts of an independent design, whether
> theological or chromosomal.
Chromosomes are not independent of the life forms in which they
are found, but part of them, and found in every cell of every existent
plant and animal.
> Ted Dace
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