On Sun, 07 Nov 1999 21:42:06 +0000, mortongr@flash.net wrote:
[continued]
GM>This
>will get to the issue that Berlinski raised in the PBS debate by asking how
>many changes are required for speciation. Kenneth Miller replied:
>"Recent studies of speciation in sunflowers have shown conclusively that a
>new species can be established in terms of speciation isolation mechanisms
>with as few as ten genetic changes." At the end of this note on phase
>spaces, I cite another example of speciation and major morphological change
>requiring only 8 genetic changes.
If the "sunflowers" remain sunflowers then this is no big deal. It might be
interesting if they changed into anything else.
GM>>**start note***
>So many Christians, like me, were taught from our earliest days in the
>faith that Darwinian mechanisms are unable to cause major innovations. A
>good friend of mine Ray Bohlin wrote a book entitled "The Natural Limits
>to Biological
>Change". I simply don't see this limit everyone wants to believe in.
It is not a case of not wanting to believe in this limit. The fact is that there
is no *evidence* that Darwinian mechanisms are able to cause major
innovations.
It is the Darwinists who need to believe their is no limit to Darwinian
mechanisms.
BTW, I am surprised here that Glenn is defending "Darwinian
mechanisms". I thought he did not believe in them?
GM>Here
>is why. Consider the sequence (allowing only A,T,C,G in the positions)
>
>A-T-G-G-C-A-T-G-C-A-C-A-T-T-G-G-A-C-T-A-G-T-C-T-A-...
>
>If I start iteratively and randomly mutating the positions, and end up with
>a sequence
>
>A-C-G-G-C-T-T-C-A-T-C-A-T-G-G-C-A-C-T-A-G-T-C-T-A-...
>
>where is the limit to this procedure? Mathematically I can change FROM any
> sequence TO any other sequence by random replacement. There is no limit
>to the sequence I can generate in this fashion.
>
>You will recognize this as DNA sequences.
>
>Now for your objection that I know you are making to the above. You will
>say that 99.9% of all sequences won't work and are fatal. That is true.
This undoes what Glenn just said: "I simply don't see this limit everyone
wants to believe in."
If DNA sequences are not free to change much without the organism dying
before reproducing, then there is a real world limit to how much change
Darwinian mechanisms can make.
Berlinski illustrated this with an example from language:
"Linguists in the 1950's, most notably Noam Chomsky and George Miller,
asked dramatically how many grammatical English sentences could be
constructed with 100 letters. Approximately 10 to the 25th power (10^25),
they answered. This is a very large number. But a sentence is one thing; a
sequence, another. A sentence obeys the laws of English grammar; a
sequence is lawless and comprises any concatenation of those 100 letters.
If there are roughly (10^25) sentences at hand, the number of sequences
100 letters in length is, by way of contrast, 26 to the 100th power
(26^100). This is an inconceivably greater number. The space of
possibilities has blown up, the explosive process being one of combinatorial
inflation. Now, the vast majority of sequences drawn on a finite alphabet
fail to make a statement: they consist of letters arranged to no point or
purpose. It is the contrast between sentences and sequences that carries the
full critical weight of memory and intuition. Organized as a writhing ball,
the sequences resemble a planet-sized object, one as large as pale Pluto.
Landing almost anywhere on that planet, linguists see nothing but
nonsense. Meaning resides with the grammatical sequences, but they, those
sentences, occupy an area no larger than a dime. How on earth could the
sentences be discovered by chance amid such an infernal and hyperborean
immensity of gibberish? They cannot be discovered by chance, and, of
course, chance plays no role in their discovery. The linguist or the native
English-speaker moves around the place or planet with a perfectly secure
sense of where he should go, and what he is apt to see.
The eerie and unexpected presence of an alphabet in every living creature
might suggest the possibility of a similar argument in biology. It is DNA, of
course, that acts as life's primordial text, the code itself organized in nucleic
triplets, like messages in Morse code. Each triplet is matched to a
particular chemical object, an amino acid. There are twenty such acids in
all. They correspond to letters in an alphabet. As the code is read
somewhere in life's hidden housing, the linear order of the nucleic acids
induces a corresponding linear order in the amino acids. The biological
finger writes, and what the cell reads is an ordered presentation of such
amino acids-a protein. Like the nucleic acids, proteins are alphabetic
objects, composed of discrete constituents. On average, proteins are
roughly 250 amino acid residues in length, so a given protein may be
imagined as a long biochemical word, one of many. The aspects of an
analogy are now in place. What is needed is a relevant contrast, something
comparable to sentences and sequences in language. Of course nothing
completely comparable is at hand: there are no sentences in molecular
biology. Nonetheless, there is this fact, helpfully recounted by Richard
Dawkins: "The actual animals that have ever lived on earth are a tiny subset
of the theoretical animals that could exist." It follows that over the course
of four billion years, life has expressed itself by means of a particular stock
of proteins, a certain set of life-like words.
A combinatorial count is now possible. The MIT physicist Murray Eden, to
whom I owe this argument, estimates the number of the viable proteins at
10 to the 50th power (10^50). within this set is the raw material of
everything that has ever lived: the flowering plants and the alien insects and
the seagoing turtles and shambling dinosaurs, the great evolutionary
successes and the great evolutionary failures as well. These creatures are,
quite literally: composed of the proteins that over the course of time have
performed some useful function with "usefulness" now standing for the
sense of sentencehood in linguistics. As in the case of language, what has
once lived occupies some corner in the space of a larger array of
possibilities, the actual residues in the shadow of the possible. The space of
all possible proteins of a fixed length (250 residues, recall) is computed by
multiplying 20 by itself 250 times (20^250). It is idle to carry out the
calculation. The number is larger by far than seconds in the history of the
world since the Big Bang or grains of sand on the shores of every sounding
sea. Another planet now looms in the night sky, Pluto-sized or bigger, a
conceptual companion to the planet containing every sequence composed
by endlessly arranging the 26 English letters into sequences 100 letters in
length. This planetary doppelganger is the planet of all possible proteins of
fixed length, the planet, in a certain sense, of every conceivable form of
carbon-based life. And there the two planets lie, spinning on their soundless
axes. The contrast between sentences and sequences on Pluto reappears on
Pluto's double as the contrast between useful protein forms and all the rest;
and it reappears in terms of the same dramatic difference in numbers, the
enormous (20^250) overawing the merely big (10^50), the contrast
between the two being quite literally between an immense and swollen
planet and a dime's worth of area. That dime-sized corner, which on Pluto
contains the English sentences, on Pluto's double contains the living
creatures; and there the biologist may be seen tramping, the warm puddle
of wet life achingly distinct amid the planet's snow and stray proteins. It is
here that living creatures whatever their ultimate fate, breathed and moaned
and carried on, life evidently having discovered the small quiet corner of
the space of possibilities in which things work.
It would seem that evolution, Murray Eden writes in artfully ambiguous
language, "was directed toward the incredibly small proportion of useful
protein forms...," the word "directed" conveying, at least to me, the
sobering image of a stage-managed search, with evolution bypassing the
awful immensity of all that frozen space because in some sense evolution
knew where it was going. And yet, from the perspective of Darwinian
theory; it is chance that plays the crucial-that plays the only-role in,
generating the proteins. Wandering the surface of a planet, evolution
wanders blindly, having forgotten where it has been, unsure of where it is
going.
(Berlinski D., "The Deniable Darwin", Commentary, June 1996, p23-25)
GM>But sequences have associated with them a mathematical object known as a
>phase space or a sequence space. Each nucleotide position becomes a
>dimension in the phase space. The sequence A-T represents a point in a two
>dimensional phase space like this (I hope transmission of this drawing
>doesn't mess this up):
[...]
GM>The phase space looks like a cavern system with passageways. The major
>caverns are the stable species the passageways are the rapidly traversed
>regions. The caverns explain the stasis of species and the narrow
>passageways explains the punctuated part of evolution. By random mutation
>of sequences one can find a path between position X and Y. There is no
>barrier or limit to change. All intervening positions allow for living
>organisms. There are isolated places like that marked Z which have no entry
>way and they may never have an organism with that genome. In that case
>there is a barrier and I can not go from X to Z.
>
>In the above example, if I did my counting correctly, only 22% of the
>locations (or sequences) allow for life, yet there are valid pathways
>between the locations.
I doubt that it is as high as 22%. But even 22% would be a problem for Darwinian
evolution.
GM>Thus to draw the point bluntly. Chimpanzee and Human each have approx.
3.5
>billion nucleotide positions. We share 98% of our DNA and thus occupy two
>closely neighboring caverns in DNA phase space.
Untill the full genomes of humans and chimps are sequenced, this is meaningless.
The original 1975 paper by King and Wilson actually found that this 98% was a
problem and they tried to explain it away.
Early indications from the sequencing organisations is that humans have about a
third more DNA than previously thought.
GM>Now, where does the information come from for these major changes? God
>designed them into the phase spaces!!!!! Life is not creating these major
>innovations. Life is DISCOVERYING what God has already created! If you
>start a creature with our DNA you get a human because our cluster of points
>is marked 'human' in the phase space. If you use a similar length DNA but
>with 1-2% changes, you can get a chimpanzee because those cluster of points
>in the phase space are marked 'chimpanzee'.
First, if God designed genetic phase space so that life would discover these major
innovations, then that would not be "chance" that Sproul and Geisler are objecting
too
Second, Glenn has no evidence that that is the way God worked. It is equally
possible that God created genetic phase space so that only a limited amount of
`discovery' was possible (eg. microevolution) and that major jumps through
genetic phase space (eg. macroevolution) required His supernatural intervention.
Even Dawkins admits that it is not possible to move from any point in genetic
phase space to any other, and that even human intelligent designers may never be
able to do it:
"Sitting somewhere in this huge mathematical space are humans and hyenas,
amoebas and aardvarks, flatworms and squids, dodos and dinosaurs. In theory, if
we were skilled enough at genetic engineering, we could move from any point in
animal space to any other point. From any starting point we could move through
the maze in such a way as to recreate the dodo, the tyrannosaur and trilobites. If
only we knew which genes to tinker with, which bits of chromosome to duplicate,
invert or delete. I doubt if we shall ever know enough to do it, but these dear dead
creatures are lurking there forever in their private comers of that huge genetic
hypervolume, waiting to be found if we but had the knowledge to navigate the
right course through the maze. We might even be able to evolve an exact
reconstruction of a dodo by selectively breeding pigeons, though we'd have to live
a million years in order to complete the experiment." (Dawkins R., "The Blind
Watchmaker," 1991, pp73-74).
But note that a omniscient, omnipotent Intelligent Designer could do it!
GM>Is this a purposiveless view of nature? Does this view destroy God's
>control? Of course, not. God designed the phase spaces and in doing so,
>God was essentially laying down a nearly undetectable railroad track which
>would lead from one animal to the next, not according to an unplanned
>sequence of events but according to His foreknowledge. In other words, God
>rigged the roulette wheel, BY DESIGN.
Again, if God laid down a "railroad track" or "rigged the roulette wheel"
then it is not chance in the senses that Sproul and Geisler object to. In that
case it would not be 2) "the lack of any cause"; or 3) "chance as a real
cause itself" because the ultimate cause was God. It would be: 1) the
"intersection of two or more lines of causality" which is compatible with
Christian theism.
Glenn's whole argument is just one big strawman!
GM>What experimental evidence is there of this? Lots. 3 or 4 mutations
>perform most of the physical transformation between two species of
>monkeyflower. These 3-4 mutations make most of the changes required to
>change the flower from a bumblebee designed flower to a hummingbird
>designed flower. See H.D. Bradshaw Jr., S. M. Wilbert, K. G. Otto and D.
>W.Schemske, "Genetic mapping of Floral Traits Associated with Reproductive
>isolation in monkeyflowers (Mimulus)," Nature, 376 Aug. 31, 1995, p. 762-765
>***end note***
The monkeyflowers all stayed within the genus Mimulus. This variability of
Mimulus was even noted by Darwin in his Origin of Species as an example of
morphological variations independent of natural selection, but he regarded them as
"of extremely small importance" and not "progressing towards a higher state of
development":
"In numerous other cases we find modifications of structure which are considered
by botanists to be generally of a highly important nature, affecting only some of the
flowers on the same plant, or occurring on distinct plants, which grow close
together under the same conditions. As these variations seem of no special use to
the plants, they cannot have been influenced by natural selection. Of their cause we
are quite ignorant; we cannot even attribute them, as in the last class of cases, to
any proximate agency, such as relative position. I will give only a few instances. It
is so common to observe on the same plant, flowers indifferently tetramerous,
pentamerous, etc., that I need not give examples; but as numerical variations are
comparatively rare when the parts are few, I may mention that, according to De
Candolle, the flowers of Papaver bracteatum offer either two sepals with four
petals (which is the common type with poppies), or three sepals with six petals.
The manner in which the petals are folded in the bud is in most groups a very
constant morphological character; but Professor Asa Gray states that with some
species of Mimulus, the aestivation is almost as frequently that of the
Rhinanthideae as of the Antirrhinideae, to which latter tribe the genus
belongs....We thus see that with plants many morphological changes may be
attributed to the laws of growth and the interaction of parts, independently of
natural selection. But with respect to Nageli's doctrine of an innate tendency
towards perfection or progressive development, can it be said in the case of these
strongly pronounced variations, that the plants have been caught in the act of
progressing towards a higher state of development? On the contrary, I should infer
from the mere fact of the parts in question differing or varying greatly on the same
plant, that such modifications were of extremely small importance to the plants
themselves, of whatever importance they may generally be to us for our
classifications. The acquisition of a useless part can hardly be said to raise an
organism in the natural scale; and in the case of the imperfect, closed flowers
above described, if any new principle has to be invoked, it must be one of
retrogression rather than of progression; and so it must be with many parasitic and
degraded animals." (Darwin C.R., "The Origin of Species by Means of Natural
Selection", [1872], Everyman's Library, J.M. Dent & Sons: London, 6th Edition,
1928, reprint, pp198-199)
GM>Is there design? Yes. Is it design as most apologists claim? No. God
>uses chance to create us, to pick disciples, to choose land etc. My God can
>controll chance--I guess Stephen's god isn't that powerful.
Again, does Glenn ever consider what God thinks of what he says?
GM>It is a shame.
>For the anti-evolutionists to constantly emphasise that God can't overpower
>chance means that they don't believe in an omnipotent God. If He were
>omnipotent, He would be able to overpower chance.
If God were omnipotent He wouldn't need to "overpower chance"! I find the way
Glenn speaks of chance as though it is an independent entity. This borders on
paganism.
Glenn is just deluding himself if he thinks that he has shown that chance in the
sense that Sproul, Geisler and myself object to, namely defined as: 2) "the lack of
any cause"; or 3) "chance as a real cause itself" has any causal reality.
I repeat that neither Sproul, Geisler or myself have any problem with God using
chance in the sense of: 1) the "intersection of two or more lines of causality".
Steve
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"One of the most surprising negative results of palaeontological research in
the last century is that such transitional forms seem to be inordinately
scarce. In Darwin's time this could perhaps be ascribed with some
justification to the incompleteness of the palaeontological record and to
lack of knowledge, but with the enormous number of fossil species which
have been discovered since then, other causes must be found for the almost
complete absence of transitional forms." (Brouwer A., "General
Palaeontology", [1959], Transl. Kaye R.H., Oliver & Boyd: Edinburgh &
London, 1967, pp162-163)
Stephen E. Jones | sejones@iinet.net.au | http://www.iinet.net.au/~sejones
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