Re: the vertebrate eye a `kludge'? (was Problems with selectionism, remarks on order, etc., etc.)

From: Chris Cogan (ccogan@telepath.com)
Date: Mon Sep 25 2000 - 00:26:45 EDT

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    At 06:17 AM 09/25/2000, you wrote:
    >Reflectorites
    >
    >On Sun, 10 Sep 2000 15:18:27 -0500, Chris Cogan wrote:
    >
    >[continued]
    >
    >CC>In fact, if we did not know
    > >better from empirical observation, and if we thought life was designed,
    > >we'd guess that life would be much different from what it turns out to be,
    > >because we'd guess that the designers would be intelligent enough, good
    > >enough biological engineers, not to design a kludge like the human wrist
    >
    >Even if we granted (for the sake of argument) that the human wrist was a
    >"kludge" the fact is that even a "kludge" is designed:
    >
    > "kludge... a system and especially a computer system made up of
    > poorly matched components"
    > (http://m-w.com/cgi-bin/dictionary?book=Dictionary&va=kludge)

    Where's the indication in this definition of "design"? Even *computer*
    kludges are not always design, but occur as the result of *failure* to
    design, or to design *sufficiently*. In Nature, of course, there is no need
    of design to have poorly matched parts.

    >BTW I would like to see Chris' *evidence* why he thinks "the human
    >wrist" is a "kludge". I must admit I have never heard of that argument in
    >the evolutionary literature. Did Chris read it somewhere (and if so where?)
    >or did he just make it up?

    I don't know where I read it; it was a long time ago. I may even have come
    across it in my Anatomy and Physiology course in high school. The wrist has
    eight bones, an evolutionary heritage from pre-primates. Even a *poor*
    engineer could design a better one with fewer parts (by better, I mean with
    a lower frequency of failure, and equal or greater flexibility and
    strength, etc.). Evolution does this because it gets itself into
    cul-de-sacs where it can't make changes sufficient to *really* fix the
    problem without having to make a genetic jump that's too big for it to make
    without making it non-functional along the way. So it produces "kludges"
    instead. These are better than nothing, but hardly ideal, biologically. A
    designer would not have this problem, because the designer can change every
    thing at once that needs changing. Thus, if there were a designer, our
    children could all miraculously have radically better wrists than we do.

    >CC>or
    > >the nerve pathways from the retinal cells in the human eye (the nerves go
    > >*in front* of the light-sensitive rods and cones, thus blocking some of the
    > >light).
    >
    >Chris does not even demonstrate that "blocking some of the light" is a
    >problem for vision. It isn't because the whole visual *system* of two eyes
    >and the brain's visual processing sub-system amply compensate for any
    >minor loss of light this might cause (which AFAIK has never even been
    >quantified).
    >
    >Nevertheless, this has been one of the classic Darwinist arguments against
    >design, as Denton explains:
    >
    > "In all non-vertebrate eyes, and in the pineal or dorsal eyes of
    > primitive
    > vertebrates, the photoreceptors point toward the light. However,
    > in the
    > vertebrate lateral eye, the photoreceptors point backwards away
    > from the
    > light towards the retinal epithelium and the choroidal blood
    > sinuses. This
    > arrangement necessitates the placement of the neural cell
    > layer--which
    > relays the visual image from the retina to the brain--between the
    > photoreceptors and the light, and results in the blind spot where
    > the axons
    > of these neural cells leave the retina for the brain via the
    > optic nerve.
    > Generations of Darwinists have seized on this apparently illogical
    > arrangement and particularly the consequent "blind spot" as a case of
    > maladaptation. The following comments by Dawkins are typical:
    >
    > "Any engineer would naturally assume that the photocells would point
    > towards the light, with their wires leading backwards towards the
    > brain. He
    > would laugh at any suggestion that the photocells might point
    > away from
    > the light, with their wires departing on the side nearest the
    > light. Yet this is
    > exactly what happens in all vertebrate eyes. Each photocell is,
    > in effect,
    > wired in backwards, with its wires sticking out on the side
    > nearest to the
    > light. This means that the light, instead of being granted an
    > unrestricted
    > passage to the photocells, has to pass through a forest of connecting
    > wires, presumably suffering at least some attenuation and distortion
    > (actually probably not much but, still, it is the principle of
    > the thing that
    > would offend any tidy-minded engineer!) (Dawkins R., "The Blind
    > Watchmaker," 1986, pp.93-94,
    >
    > (Denton M.J., "The Inverted Retina: Maladaptation or
    > Pre-adaptation?" Origins &
    > Design, Vol. 19, No. 2, Access Research Network, 1999.
    > http://www.arn.org/docs/odesign/od192/ir192summ.htm).
    >
    >Ayoub in 1996 had looked at this (again no pun intended!) from the angles
    >of 1. Regenerating photoreceptive pigments; 2. Recycling of
    >photoreceptive material; and 3. Absorption of excess light; and then
    >conducted a thought experiment with the photorectors and retina reversed:
    >
    > "So, as a thought experiment, let's fix the blind spot. We will
    > start
    > by turning the photoreceptors around, so their wiring isn't in the
    > way. We have eliminated the blind spot, providing slightly better
    > sight in one portion of the eye. Now, however, the blood vessels
    > and RPE, needed to maintain the photoreceptors, must be located
    > on the inner side of the retina, between it and the lens. This
    > places a
    > large capillary bed (containing many red blood cells) and an
    > epithelial tissue in the path of the light, significantly
    > degrading the
    > visual information passing to the photoreceptors. Furthermore,
    > since the photoreceptors continually shed material from their outer
    > segments, dumping this opaque waste in the path of the light would
    > greatly diminish the amount of light reaching the photoreceptors.
    > Our proposed change also reduces the quality of the light, by
    > refracting it with the opaque pieces of shed outer segment
    > membrane. We might imagine simply placing the RPE at the back
    > of the retina, but this raises the problem of how to dispose of
    > spent
    > outer segment membranes, so that the photoreceptors can be
    > quickly regenerated. Or, perhaps, we could surround each
    > photoreceptor cell by RPE cells, but this would need increase the
    > space between the photoreceptors, thus decreasing the resolution of
    > vision. These design changes may force temporal or spatial
    > decrements in vision. Are these improvements? Hardly; indeed, our
    > thought experiment has taken the vertebrate eye rapidly downhill.
    > In trying to eliminate the blind spot, we have generated a host of
    > new and more severe functional problems to solve. Our "repair"
    > seems far worse than the apparent flaw we wanted to fix." (Ayoub
    > G., "On the Design of the Vertebrate Retina," Access Research
    > Network, Origins & Design, Vol. 17, No. 1, 1996.
    > http://www.arn.org/docs/odesign/od171/retina171.htm)
    >
    >The above would be sufficient to establish that the vertebrate eye is not
    >badly designed and may in fact be *well*-designed.

    A *thought* experiment from someone published at ARN? Surely, you're joking.

    The fact is that the eyes of many organisms *are* built the "right" way
    around. How do *they* do it, if it's such a bad idea? Perhaps Ayoub did not
    want to be bothered by actually existing counterexamples; those pesky
    *facts* do often get in the way of nice design-theory ideas, don't they?
    Notice that at least some of the "restrictions" Ayoub assumes for the
    alternative need not apply, if other changes are made as well (as,
    *presumably*, a *designer* could well ensure, *couldn't* he?).

    >But then in 1999 Denton considered the fact that land-dwelling vertebrate
    >vision requires a lot of oxygen:
    >
    > "The remarkable capacity of the unique choriocapillaris system to
    > deliver copious quantities of oxygen to the photoreceptors has an
    > important consequence--it obligates the necessity for a capillary
    > network within the photoreceptor layer and this in turn allows the
    > photoreceptor cells to be packed tightly together, thus maximizing
    > the resolving power of the eye. It is also hard to imagine how a
    > standard-type capillary network to carry the necessary quantities of
    > blood directly through the photoreceptor cell layer could be
    > arranged without causing at least some decrease in the packing
    > density of the photoreceptors and a consequent decrease in the
    > resolving power of the eye. (Interestingly, in all known high-acuity
    > eyes, including the compound eyes of insects and other arthropods
    > and the camera-type eyes of various groups, including the
    > cephalopod and photoreceptors, are packed tightly together and not
    > separated by either blood vessels or any other type of intervening
    > tissues or structures.)" (Denton, 1999).
    >
    >So therefore it seems that the vertebrate retina is *better* placed where it
    >is behind the photoreceptors:
    >
    > "Taken together, the evidence strongly supports the notion that the
    > inverted retina and its major consequence (the positioning of the
    > photoreceptors in the outer section of the retina where they are in
    > intimate contact with the choriocapillaris) is a specific adaptation
    > designed to deliver abundant quantities of oxygen to the
    > photoreceptor cells commensurate with their high energy demands-
    > -especially in metabolically active groups such as the birds and
    > mammals. Rather than being a case of maladaptation, the inverted
    > retina is probably an essential element in the overall design of the
    > vertebrate visual system. This conclusion is reinforced by the
    > difficulty of envisaging alternative means of delivering the
    > required
    > amounts of oxygen to the photoreceptor cell layer if the retina had
    > the typical non-inverted design of the sort that might appeal to a
    > "tidy-minded engineer." (Denton, 1999).
    >
    >One mark of a good theory is when one of its claimed major weaknesses
    >turns out to be one of its major strengths. In the case of the vertebrate
    >eye,
    >far from being badly designed, it turns out the counter-intuitive placement
    >of the photoreceptors in front of the retina is an example of *good* (I
    >would say *brilliant* but I'm biased! :-)) design!
    >
    >But (as the TV commercial says) there's more (i.e. it gets worse for the
    >Darwinists). Since this design decision was made before the vertebrate-
    >invertebrate split about1 billion years ago:
    >
    > "I wouldn't be surprised if the common ancestor of all surviving
    > animals, who lived perhaps a billion years ago, possessed eyes."
    > (Dawkins R., "Climbing Mount Improbable," 1996, p.128)
    >
    >it actually is a good example of far-sighted (again pun unintended!) design
    >for vision on land which would not be needed until about 600 million years
    >later:
    >
    > "Finally, there is the fascinating question of pre-adaptation.
    > Although all vertebrates have the same inverted design the
    > interesting question arises as to whether the inverted design is a
    > necessity for high-resolution vision in the cold-blooded vertebrates
    > such as fish which have lower metabolic rates than the warm-
    > blooded vertebrates such as mammals and birds. In this context the
    > high resolution eye of the cephalopods, including the octopus and
    > squid, is instructive. The cephalopods have a typical non-inverted
    > retina which is comparable in resolving power to the eyes of many
    > vertebrates, have metabolic rates similar to that of fish and other
    > cold- blooded vertebrates (even though the maximum oxygen
    > capacity of cephalopod blood is only one third that of a fish), and
    > inhabit an aquatic environment similar to that of many fish. This
    > implies strongly that high- acuity vision in the eyes of
    > cold-blooded
    > vertebrates would be possible with a non-inverted retina and that it
    > is only in the case of the higher and warm-blooded vertebrate
    > species where the metabolic rates are far higher that the inverted
    > arrangement to bring the photoreceptors adjacent to the choroidal
    > vessels is a necessity for phototransduction. In other words, the
    > inverted retinal design is almost certainly not an adaptive
    > necessity
    > in cold-blooded vertebrates." (Denton, 1999).
    >
    >CC>Things like the wrist *do* have evolutionary explanations,
    >
    >It depends on what Chris means by "evolutionary explanations". If he
    >means that random mutation and natural selection can provide a plausible,
    >complete, and testable explanation of the origin of the human wrist, I
    >would be interested to see it.
    >
    >But of couse even if Chris could provide a plausible, complete and testable
    >Darwinian "evolutionary explanation" of the origin of the human wrist, that
    >fitted all the known facts, he would have to face the fact that more than
    >one theory can be supported from the same facts:
    >
    > "Scientists whose theories make seemingly improbable events very
    > probable, and who then, when these events are observed,
    > congratulate themselves on being right, are often dismayed to find
    > that other theories predict the same events and have the advantage
    > of actually being right. (Yet remember that it is possible for
    > evidence to support a theory despite also giving support to a
    > competing theory....)" (Leslie J., "Universes," Routledge: London,
    > 1996, p.155)
    >
    >What Chris would need to show is that *only* an "evolutionary
    >explanation" would fit all the facts.
    >
    >CC>but no
    > >design explanations, unless you count "Well, that's just the way the
    > >designers chose to do it;
    >
    >Not really. A good "design explanation" could be made of the human wrist
    >conforming to the same basic vertebrate limb plan on the principle of
    >variation on a theme:
    >
    > "Notice, this is exactly what we would expect as evidence of good
    > creative design and engineering practice. Suppose you were in the
    > bridge-building business, and you were interviewing a couple of
    > engineers to determine whom you wanted to hire. One fellow says,
    > "Each bridge I build will be entirely different from all others."
    > Proudly he tells you "Each bridge will be made using different
    > materials and different processes so that no one will ever be
    > able to
    > see any similarity between the bridges I build. " How does that
    > sound? Now the next fellow comes in and says, "Well, out back in
    > your yard I saw a supply of I-beams and various sizes of heavy
    > bolts and cables. We can use those to span either a river or the San
    > Francisco Bay. I can adapt the same parts and processes to meet a
    > wide variety of needs. You'll be able to see a theme and a variation
    > in my bridge building and others can see the stamp of authorship in
    > our work." Which fellow would you hire?" (Parker G.E., "Creation:
    > the Facts of Life", 1980, p.26)
    >
    >And what is Chris' "evolutionary explanation"? Is it "Well, that's just the
    >way the" `blind watchmaker' "chose to do it"?
    >
    >CC>who are we to question why the designers did
    > >things the way they did?"
    >
    >Chris is getting confused between `why' "explanations" and `that'
    >"explanations".
    >
    >We don't need to know "why" even human designers designs things in
    >order to know *that* they are designed:
    >
    > "Moreover, the specifics of design-purpose, plan, intent, function-
    > may be unrecognized even when designedness is evident. The
    > Smithsonian Institution has a collection of obviously designed
    > human artifacts, concerning the purposes of which no one has a
    > clue. In any case designedness and artifactuality, although they are
    > closely linked, are not coextensive, and recognition of designedness
    > s typically subordinate to, even dependent upon, recognition of
    > rtifactuality." (Ratzsch D., in Dembski W.A., ed., "Mere Creation,"
    > 998, p.294)
    >
    >If SETI receives a message from aliens SETI would not have to explain
    >"why" the aliens sent the message to know that it is designed.
    >
    >In the case of the vertebrate eye having its photoreceptors `wired
    >backwards' we can in fact provide a good "why" explanation. But in other
    >cases it might be more difficult.
    >
    >CC>This last, of course, is not an explanation *at all*.
    > >>It's the *evasion* of explanation.
    >
    >Who said it was an "explanation"? Unless Chris can provide details where a
    >leading design theorist provided such an explanation it is just a straw man,
    >set up to be knocked down.
    >
    >CC>It's the assertion that what we
    > >*do* know (that other organisms have properly-built eyes, for example)
    >
    >See above. The invertebrate eye is "properly-built" built for a marine
    >invertebrate existence where high-resolution, long distance vision is not
    >necessary, by having the photoreceptors behind the retina.
    >
    >But the *vertebrate* eye is also "properly-built" built for a *land*
    >vertebrate existence where high-resolution, long distance vision *is*
    >necessary, by having the photoreceptors in front of the retina so the latter
    >has accesss to a strong blood supply without *really* obscuring vision.
    >
    >CC>should be *set aside* in deference to the mindless "Well, that's just the
    > >way they did it" excuse.
    >
    >See above. It turns out that it is the *anti-designist* objection which is
    >the
    >"mindless" one. I bet the anti-designists like Chris just just keep on
    >believing it anyway, despite the new evidence that the vertebrate eye is very
    >well designed.
    >
    >CC>It is a demand on the part of ID theorists that we
    > >ignore the *facts* of biological reality
    >
    >In fact it is the "ID theorists" who are pointing out to anti-designists what
    >*are* "the *facts* of biological reality" and it is the *anti-designists* who
    >are doing the ignoring!
    >
    >CC>in favor of a belief in designers
    > >whose minds are not known
    >
    >See above. It is not necessary that the "designers ...minds are... known". It
    >is enough to know that there *is* evidence of design.
    >
    >But of course the *Christian* design theorists do not claim that the
    >Designer's mind is not known, since they claim He has communicated a
    >great deal of what is in His mind to man.
    >
    >CC>and who, judging from their work, are *idiots*
    >
    >So Chris believes that he (including his mind and reasoning) was designed
    >by "idiots"?
    >
    >I extend him my sympathy. I believe that I (including my mind and
    >reasoning) was designed by *very* Intelligent Designer"!
    >
    >Chris has the same self-referential problem that Darwin had. If his theory
    >was true, there would be no reason to believe that his theory was true:
    >
    > "Charles Darwin himself once said, "The horrid doubt always arises
    > whether the convictions of man's mind, which has developed from
    > the mind of the lower animals, are of any value or at all
    > trustworthy. Would anyone trust the conviction of a monkey's
    > mind, if there are any convictions in such a mind?" In other words,
    > if my brain is no more than that of a superior monkey, I cannot even
    > be sure that my own theory of my origin is to be trusted. Here is a
    > curious case: If Darwin's naturalism is true, there is no way of
    > even
    > establishing its credibility let alone proving it. Confidence in
    > logic is
    > ruled out- Darwin's own theory of human origins must therefore be
    > accepted by an act of faith. One must hold that a brain, a device
    > that came to be through natural selection and chance-sponsored
    > mutations, can actually know a proposition or set of propositions to
    > be true." (Sire J.W., "The Universe Next Door," 1988, p94)
    >
    >CC>Naturalistic evolution gives us a means of *understanding* why these crazy
    > >facts *are* facts, because it gives us a means of showing how they arose
    > >out of the accidents of history.
    >
    >Not really. "Naturalistic evolution" just *assumes* up front that
    >these "facts" are "accidents of history" and then proceeds to
    >interpret the "facts" consistent with that original assumption.
    >
    >In any event, since Chris thinks his mind has been designed by "idiots" then
    >he would not know that his "understanding" of the facts was reliable.
    >
    >After all, no one would trust the output of a computer that was produced
    >by designers "who judging from their work, are *idiots*"
    >
    >CC>These and many other facts make *sense* naturalistically,
    >
    >See above. By Chris' own admission his "sense" has been produced by
    >"idiots". So on that basis his perception of what "make *sense*
    >naturalistically" is likely to be unreliable.
    >
    >But in any event, "the facts" of the vertebrate eye *don't* "make sense
    >naturalistically". Naturalistic `blind watchmaker' evolution could not
    >explain why what they regard as an inferior type eye arose in the first place
    >and then persisted for 600 million years in a marine environnment in which,
    >by their own admission it had a disadvantage, until it became advantageous
    >about 400 million years ago when vertebrates came onto the land.
    >
    >But from my `far-sighted Intelligent Designer' perspective I can offer an
    >explanation why 1 billion years ago the vertebrate and invertebrate eye
    >diverged, when it had no immediate advantage, and then about 400 million
    >years ago when vertebrates came onto the land the advantage of front
    >photoreceptors became apparent.
    >
    >Now I would like to see Chris' explanation that "makes *sense*
    >naturalistically", of why this grand-daddy of all pre-adaptations occurred 1
    >billion years ago when by his own claim it is supposed to be a bad design?
    >
    >CC>but they *don't* make sense in *intelligent* design terms.
    >
    >How would Chris *know* that "they *don't* make sense in *intelligent*
    >design terms" when he is obviously so highly prejudiced against ID that he
    >could not understand it if he wanted to (which he doesn't)!
    >
    >But I have provided above explanations that "make sense in *intelligent*
    >design terms". Now it is Chris' turn to show how they "make sense in"
    >naturalistic evolution "terms", i.e. the "work" of "*idiots*".
    >
    >CC>That's why ID theorists do *not* have an ID *explanation* for these
    > >facts.
    >
    >I wonder which "ID theorists" Chris asked? The eye explanations have
    >been on the main "ID theorists" web site since mid-1996 and early 1999.
    >
    >CC>That's why they are forced to hem and haw and claim, totally without
    > >evidence, that their designer must have reasons of which we do not know.
    >
    >See above. There is no requirement to know the designer's "reasons" to
    >know that something has been designed. However in some cases the
    >designers reasons can be inferred.
    >
    >CC>They are, in effect, using the *failure* of their theory to "justify" a
    > >bizarre *extension* of it.
    >
    >The "theory" would only be a "failure" if it in fact was what Design
    >theorists claimed. But AFAIK no Design theorist has ever claimed to know
    >in detail the designer's "reasons".
    >
    >CC>Now the designers are intelligent, but *we* have
    > >no means of understanding their intelligence.
    >
    >Chris is *really* getting confused. First, he claims he can judge from the
    >designer(s) "work" that they "are *idiots*" which must mean he claims he
    >can have *some* understanding" of "their intelligence"
    >
    >Second he confuses not knowing the the designer's "reasons" with not not
    >having some "understanding" of "their intelligence".
    >
    >If SETI received a signal in a high-level mathematical code, as in the movie
    >"Contact" we would know that the minimum level of "intelligence" of the
    >sender was high, but we might not know much about their "reasons" for
    >sending the message.
    >
    > >From my `far-sighted Intelligent Designer' perspective I could infer from
    >the evidence of the vertebrate eye being prepare 600 million years in
    >advance that the Designer's intelligence is very great indeed!
    >
    >CC>On what grounds then, can they be said to *be* intelligent?
    >
    >See above. Chris original premises are faulty and therefore so is his
    >conclusion.
    >
    >CC>In short, ID theory demands that we are to subvert our ability to
    > >understand physical reality and even to think logically in favor of a
    > >nearly mindless acceptance of a belief in a gang of unknown idiots
    >
    >See above.
    >
    >CC>This epistemological subservience to blind faith is the real horror. "Junk
    > >your knowledge of physics, chemistry, geology, and genetics!
    >
    >I sometimes wonder who Chris is *really* attacking. No Design theorist
    >that I am aware of advocates `blind faith'. In fact the only advocates of
    >`blind faith' that I know of are two Christian evolutionists Cliff Hamrick
    >and Pim van Meurs (alias FMAJ1019).
    >
    >If Chris so dislikes "blind faith" why didn't he take it up with Cliff at the
    >time and why doesn't he take it up with Pim/FJ now?
    >
    >I certainly do not regard my "faith" as "blind"!
    >
    >CC>Throw out your knowledge of the history of life on Earth!
    >
    >Another straw man. In fact it is "knowledge of the history of life on Earth"
    >that is providing more evidence for Design and more problems for
    >Naturalistic Evolution!
    >
    >CC>Ignore the many facts of life
    > >that make sense in naturalistic terms but yield nothing but excuses and
    > >emptiness in intelligent design terms.
    >
    >See above explanations "in intelligent design terms" about the vertebrate
    >eye. I wonder what "excuses and emptiness" Chris will offer in reply?
    >
    >CC>Don't think, *believe!* Don't question the human wrist,
    >
    >I still am not clear what Chris thinks the problem with "the human wrist". It
    >seems to me to have a remarkably versatile design.
    >
    >CC>take it on faith that the designers knew what
    > >they were doing;
    >
    >There is nothing strange in that. We usually assume that "designers knew
    >what they were doing" even if we don't always understand why they did it.
    >
    >CC>it doesn't work well, but who are *we* to question the
    > >wisdom of the great and wonderful designers?" Etc., etc., etc.
    >
    >Chris's first task is to establish that "it *doesn't* work well".
    >
    >The human wrist and the vertebrate eye in fact do at least "work well".
    >What does Chris want a corksrew for opening wine bottles for one and
    >screw-in telescope attachments for the other?
    >
    >CC>(Sorry. Sometimes I get carried away by the endlessness of the evasions
    >and
    > >nonsense and anti-science coming from the ID camp.)
    >
    >I sometimes wonder who exactly Chris has these discussions with in the
    >"ID camp". It sounds to me like he also has an `imaginary friend' who puts
    >up nice and easy straw man ID answers so that Chris can feel good
    >knocking them down!
    >
    >I have answered Chris' questions point-by-point, spread over four
    >messages. Now let's see who is indulging in "evasions", "nonsense" and
    >"anti-science"!
    >
    >Steve
    >
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