Denton vs Squid; the eye as suboptimal design.

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In a recent article in Touchstone Magazine, Jonathan Witt, fellow for the Discovery Institute’s Center for the renewal of science and culture, has written a review of Francis Collins’ book “ The Language of God: A Scientist Presents Evidence for Belief”. Amongst other things in this review he claims that Michael Denton has demonstrated that the “backwards wiring” of the mammalian retina improves oxygen flow and is good design.

Denton of course, has done no such thing. Since I am on a role with things visual, I am reposting an updated version of an earlier article on this topic.

Just to recap, vertebrates (like ourselves), and the invertebrates Squid and Octopi have “camera eyes”. They differ in how the photoreceptors in the retina, the part of the eye that receives the image, is wired up to the brain. The vertebrate wiring system is often cited as an example of “bad”, or at least quirky, design that is explainable by evolution.

The vertebrate retina is wired “backwards”. That is the photoreceptors point to back of the retina, away from incoming light, and the nerves and blood vessels are on the side of the incoming light, this means that any image formed on the vertebrate retina has to pass though layers of blood vessels and ganglion cells, absorbing and distorting the image.

To get decent visual acuity, vertebrates must focus light on a small patch of retina where the blood vessels and nerves have been pushed aside, the fovea. This patch must be small because of the nutrient requirements of the retina. Also, the construction of the vertebrate retina means that blood vessels and nerves must pass through the retina, creating a “blind spot”, where no image is formed. Finally, the “backwards” retina means that vertebrates have a high risk of retinal detachment. Altogether this shows that having the nerves and blood vessels in front of the photoreceptors is less than optimal design.

Imagine taking a pane of glass, then smearing it thickly with vaseline, then wiping a tiny hole in the vaseline. That is what the vertebrate retina is like.

Now consider the eye of squids, cuttlefish and octopi. Their retinas are “rightway round”, that is the photoreceptors face the light, and the wiring and the blood vessels facing the back (1). Squid and octopi have no blind spot; they can also have high visual acuity. The octopus also has a fovea-equivalent structure, which it makes by packing more (or longer) photoreceptors into a given area (1). Because it doesn’t have to create a hole in the supporting tissue it can have arbitrarily large “fovea”, and greater visual acuity. Cuttlefish have better visual acuity than cats (2) and because of their “rightway round” retinas; this level of acuity covers nearly the entire retina (1,2) unlike vertebrates where it is confined to the small spot of the fovea.

The vertebrate retina is a prime example of historically quirky “design”. The vertebrate retina is backwards because the development of the retina was first elaborated in rather small chordates, where issues of acuity and blind spots were non-existent; all subsequent vertebrates got stuck with this “design”. Vertebrates do very well with the limitations of the design of the eye, but it is clear that this is no system a competent designer would make. Naturally, this annoys the proponents of an Intelligent Designer, and they have been looking for ways to put a better spin on the kludged design of the vertebrate eye.

ID advocates have a hard time dealing with the quirky design of the eye, both Witt and Behe have used the “better blood flow” argument in order to show the backwards retina really is good design.

This invokes an argument that has been doing the rounds of creationists for a while. The True.Origins site (which is a rip-off of Talk.Origins) has a page that claims that the “backwards” retina improves the blood supply. It is probably the canonical page where these claims come from. Denton’s argument is slightly different, but follows on from the canonical creationist argument, so I will deal with the creationist argument first.

In vertebrates, underneath the photoreceptors is a layer of pigment and pigment cells called the choroid (the squid, cuttlefish and octopus have similar arrangements - more on this later), this layer of pigment absorbs stray light that is not caught by the photoreceptors, which might reflect back and fuzz up the image.

In terrestrial vertebrates, the amount of light landing on the retina produces a significant amount of heat, enough to damage the retina itself (3,4). The True.Origins page gives the impression that it is light focused on the retina that produces the heat. The article implies that by having the most thermally sensitive bit of the photoreceptor bang up against a heat sink (the blood vessels of the choroid, whose rapid blood flow removes the heat, see below), vertebrates can tolerate light intensities that “right way round” retinas could not.

However, when one reads the paper they reference (3), a completely different picture emerges.

It is the choroid itself that generates the heat that threatens the retina! As noted above, the pigments in the choroid absorb light that is missed by the photoreceptors. This light is re-radiated as heat. 25-30% of the light falling on the retina ends up being absorbed by the choroid and re-radiated as heat (3,4). So we have the most thermally sensitive part of the photoreceptors bang up against the bit that generates the most heat. Good design? I think not.

To cool down the choroid, very fast blood flow through the tissues below and in the pigment layer is needed (3,4). But let’s be clear about this, the Creationists have it back to front. The “backwards” arrangement of the vertebrate retina does not make possible fast blood flow, it requires fast blood flow to cool the tissue down. This is yet another area where vertebrate design is flawed, with the fragile photoreceptors hard up against the source of the damaging heat.

Of course, the question of why fish, which have more species than all terrestrial vertebrates combined, must suffer with a backwards retina so that terrestrial vertebrates can have high blood flows to an area that wouldn’t need them if the system was designed correctly in the first place, is never addressed. The other question is why terrestrial gastropods which have camera eyes have a “right way round” retina if invert retinas are important for terrestrial vision? Their camera eyes are relatively small compared to terrestrial vertebrates, and so should loose heat readily. However, arthropod eyes of this size are subject to light-induced retinal damage. See the references in this paper.

In squid, octopi, cuttlefish and terrestrial gastropods, the pigment layer is below the photoreceptors, in an area of dense blood vessels (1). This arrangement blocks stray light and provides sufficient blood flow to cool the tissue and provide nutrients without the added layers of ganglion cells over the top of the photoreceptors that distort and absorb the image. Even better, squid, octopi and cuttlefish do not have the most thermally sensitive part of the retina next to the source of waste heat, as it is in vertebrate eyes, needing an outrageous amount of blood flow to cool the system.

The vertebrate eye does very well indeed, but it is a kludge. The fovea is a cute trick to squeeze greater acuity out of a flawed design, but octopi and squid do it better. The cooling blood flow to the choroid is needed as the pigments of the choroid generate waste heat, but this is irrelevant to whether the photoreceptors are forward or reverse facing. The arrangement of the vertebrate eye does not improve the blood supply, and it looks like the vertebrate eye has to kludge up a high blood flow to the choroid because the vertebrate inverted retina is poorly designed to get blood to where it is needed.

This brings us to Denton’s argument. This is that the blood flow through the choroid needs to be high for the metabolic requirements of the retina. This is a variant of the “cooling bath” concept, and has exactly the same problems. The retina is an energy hungry system, but it doesn’t need to be inverted to get a high blood flow. In fact, the way the vertebrates do it is just plain silly. Molecules used for providing the energy to run light detection are formed in the mitochondria in the cell body from blood born nutrients, then passed along to the photoreceptors in the modified cilia projecting from the cell body (see diagrams in links above). As the retina is invert, the cell bodies are further away from the choroid, with the light harvesting disks between them and the choroid. Consequently, all blood born nutrients delivered by the choroid in vertebrates must diffuse from the choroid, through the pigmented epithelium, then past all the photoreceptor disks to the mitochondria in the cell body to be used (and all waste diffused in the reverse direction). Delivery from the cell body end would result in a shorter diffusion distance through less restricted space; ie, more efficient delivery. This point is born out by the fact that choroid oxygen tension drops by only 3% from artery to vein. In consequence, the retinal artery, though it only carries 5% of the blood supplied to the retina, carries 40% of the oxygen used by the retina.

Denton says

Blood absorbs light strongly, .… From this we can immediately discount one possible way of supplying the photoreceptors in a non-inverted retina where the photoreceptor would form the inner layer–pointing directly towards the light, i.e., by placing a choriocapillaris-type system of blood vessels in front of the photoreceptor cells, i.e., between the photoreceptors and the light. While such an arrangement might well deliver sufficient quantities of oxygen to the photoreceptors, the sensitivity and acuity of any such hypothetical “eye” would be greatly diminished by the highly absorbent complex of blood vessels positioned between the light and the photoreceptor layer

This is pretty silly, with the current arrangement, the photoreceptors have a range of ganglion cells, supporting cells, nerve cells and blood vessels already piled thickly on top of it (when you look into the eye with and ophthalmoscope, you can see the superficial blood vessels on top of the retina, there are also capillaries that dive deep into the cell layer as well. The retina already has a mass of blood, and lots of other things, getting in its way. Of course there is a better way to do it, the way cephalopods do it.

In cephalopods the blood vessels are right next to the terminal parts of the photoreceptor process, the photoreceptor cell bodies and the pigment cells where it is needed. You can see the blood vessels and pigments in this paper on the octopus retina. It is far more efficient than the vertebrate system for both cooling and nutrient delivery. No wonder cephalopods require a much smaller blood supply to the eye.

Both the “cooling bath” and the “nutrient/oxygen delivery” arguments actually reveal that the vertebrate eye is a kludge. The high flow rates are required because the quirky design means more efficient methods can’t be used.

Denton brings in other arguments for the “superiority” of the vertebrate “back-to-front” retina, but they are irrelevant. Fore example, vertebrate photoreceptors can detect a single photon as he claims, great, but so can cephalopod photoreceptors, and they are not covered with gunk that absorbs or scatters the incoming photons. Cephalopods occupy many niches, from shallow water tidal zones with high light intensities to the abyssal depths where every photon counts, some are ambush predators, and some are active hunting predators. Some see in black and white, some see in colour, some see polarized light (which vertebrates can’t). Many have visual acuity equivalent to many vertebrates; cuttlefish have equivalent visual acuity to cats as befits their status as active hunters. All this without an invert retina. When Denton says

that in redesigning from first principles an eye capable of the highest possible resolution (within the constraints imposed by the wavelength of light16) and of the highest possible sensitivity (capable of detecting an individual photon of light) we would end up recreating the vertebrate eye

he is just plain wrong.

The pre-adaptation concept Denton prattles on about is nonsense. We are to expect that an intelligent designer will give the marine vertebrates, which are significantly more numerous in species and population than the terrestrial vertebrates, a poorly designed retina so that a very few percent of all terrestrial vertebrates can have supposedly superior vision? This is a definition of “good design” of which I was not previously aware. And again, cephalopods do it better.

Let’s be clear, the vertebrate eye works, and works rather well given its limitations (one merely has to contemplate the visual acuity of the eagle to see that the “design” works well). But it is a suboptimal Heath Robinson “design” where the limitations of the original invert retina setup (which were irrelevant to amphioxus and the small chordates in which the vertebrate eye evolved) are worked around by kludges. It is like claiming that the misground Hubble mirror with its correcting lenses is the “best possible design” because it gives clear pictures.

Once again, the vertebrate eye fails as Intelligent Design. ID proponents loudly proclaim they are not creationists and one is left to wonder why they have appropriated a bad Creationist argument.

(1) Matsui S et al., Adaptation of a deep-sea cephalopod to the photic environment. Evidence for three visual pigments. J Gen Physiol. 1988 Jul;92(1):55-66 (2) Schaeffel F, Murphy CJ, Howland HC Accommodation in the cuttlefish (Sepia officinalis). J Exp Biol. 1999 Nov;202 Pt 22:3127-34. (3) Parver LM. Auker CR. Carpenter DO. The stabilizing effect of the choroidal circulation on the temperature environment of the macula. Retina. 1982, 2(2):117-20. (4) Parver LM. Temperature modulating action of choroidal blood flow. Eye. 1991;5 ( Pt2):181-5. (5) Denton, M The Inverted Retina: Maladaptation or Pre-adaptation? Origins & Design 19:2

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112 Comments

he claims that Michael Denton has demonstrated

Gee, isn’t it surprising that Witt never mentions the fact that Denton used to be a Fellow at Discovery Institute, but left because he thinks ID is a load of crap . … . … .

I’ve heard repeatedly that Denton left the DI and pretty much repudiated the crap he used to write, but I haven’t been able to find a source for this claim.

Anyone have a link?

Denton brings in other arguments for the “superiority” of the vertebrate “back-to-front” retina, but they are irrelevant. Fore example, vertebrate photoreceptors can detect a single photon as he claims…

The Celestial Grammar Teacher calls thee SINNER!

:-)

It’s worth noting that certain aspects of cephalopod eyes are a bit of a kludge as well. Most cephs have holes in the middle of their lens. Why? Because they evolved from primitive pinhole eyes as found in modern Nautilus. It’s a really stupid system that just happens to work better than no lens at all.

But if you could combine a vertebrate lens and iris with the cephalopod retina and related structures, you might actually get an eye that could seem intelligently designed.

“Seem” being the key word, but it’s irrelevant because we still don’t have any eyes remotely like that. We just have really stupid ones.

Michael, Ian could rip the terminal e off of “fore” and stick it onto the end of “blood born.” These slips are not to be borne. Oh, wait, maybe they are. I’m terminally confused. :-)

The Celestial Grammar Teacher calls thee SINNER!

:-)

**Applause**

Nowth thay ith wif a lisp.

.…ersorrymycelestialpronunciationteachertookadayoff

as did.…my c*!!*stia! punct:[Enable javascript to see this email address.] over!ord.

Glory to the great Kosmic spller indy skye. Praise her vowels and share the grammer.

//end sillyness (for now)

If I understand this right, the great I designer (yes first person singular) up in heaven (blessed be her drafting team) saw a need for TV and to facilitate this made sure we could pixelate when we were still swimming in the oceans. Brings a new meaning to being post literate. Makes sense to me.

Ya Know, down here on earth, us mere-mortal engineer types go to battle with conflicting design requirements every day (think battery life versus processor power, for example).

Despite this - and I know this is hard to believe - we are sometimes able to work two or even three core requirements into one single product!.

So I’m a little disappointed to hear that the Big Draftsman in the Sky couldn’t take his successful arthropod design and retrofit it to my poor little peepers.

Maybe he was too busy that day to hit the foundry twice. Hmm, but that might imply that our creation was an afterthought when he got done with the squids, and he was just using up old parts. Either that, or he made us first, and we weren’t important enough in his mind to go back and fix.

Of course, we are made in His image, so maybe it’s just that he’s nearsighted.

Hmmm. none of these options is particularly comforting to me.

Maybe he was too busy that day to hit the foundry twice.

Maybe she/they/himself mixed up the petrie dishes before they went into the incubusator .….or should that be succubus-ator?

The incompetent designer.

There might be room for a class action suit there.

Vertebrates do very well with the limitations of the design of the eye, but it is clear that this is no system a competent designer would make.

The same can be said about the Ford Pinto, but no one would claim that it wasn’t designed. This is nothing more than another version of the old “God wouldn’t have done it that way” argument, which raises the question of what is a theological premise doing in what is supposed to be a scientific argument? Perhaps there is some new scientific reasearch studies that comfirm an hypothesis about what God would or would not have done? If no such studies exist (and surely they don’t), then claiming that the supposed “sup-optimal’ design of this or that biolgical system demonstrates there was no design at all is little more than hand waving speculation. There simply is no scientific basis to say that sub-optimal design equals no design. Once again the metaphysical presuppositions overshadow the science. When will you guys admit it.

Ian Musgrave Wrote:

[Some cephalopods] see polarized light (which vertebrates can’t).

Actually, most humans can, especially with practice. The image you can see is known as Haidinger’s brush. It looks like two short blue bulbs in the direction of polarization, and two longish yellow bulbs in the perpendicular direction. The image is quite faint, but unmistakeable. Without special equipment, it’s easiest to see around the time of sunset while looking towards the zenith.

A full explanation of this phenomenon is still unknown. So far as I am aware, no known photographic technique captures the apparent image.

See also the July and August 2005 issues of Sky and Telescope, and the classic Marcel Minnaert Light and Color in the Outdoors.

Ian Musgrave Wrote:

[Some cephalopods] see polarized light (which vertebrates can’t).

Actually, most humans can, especially with practice. The image you can see is known as Haidinger’s brush. It looks like two short blue bulbs in the direction of polarization, and two longish yellow bulbs in the perpendicular direction. The image is quite faint, but unmistakeable. Without special equipment, it’s easiest to see around the time of sunset while looking towards the zenith.

A full explanation of this phenomenon is still unknown. So far as I am aware, no known photographic technique captures the apparent image.

See also the July and August 2005 issues of Sky and Telescope, and the classic Marcel Minnaert Light and Color in the Outdoors.

There simply is no scientific basis to say that sub-optimal design equals no design. Once again the metaphysical presuppositions overshadow the science. When will you guys admit it.

Really? Seems to me that ID making any statement that anything was ‘designed’ or ‘designed well’ (which happens routinely) is a metaphysical presupposition that overshadows science. When when you guys admit that?

ID is more than happy to say “oh this is designed well, so of course God Did It”, and yet when something quite poorly put together is pointed out, ID advocates pompously declare “oh, it’s not valid science to try and second-guess what the Designer would or would not do!” You can’t have it both ways.

The same can be said about the Ford Pinto, but no one would claim that it wasn’t designed.

Au Contraire, Donald.

The Ford Pinto was actually a pretty reasonable design at the time, given the prevailing constraints the engineers were working with.

That period in automotive history was marked by the sudden demise of the American luxo-boat in the aftermath of the Arab oil embargos of ‘73.

American manufacturers found themselves scrambling to compete with Japanese and European builders with decades of experience and infrastructure for making small, attractive cars (like the Honda CVCC).

You can’t just downsize components when you’ve just built engine-specific plants for making big V-8’s, and, while the body-on-frame system that most American cars used was poorly suited for an econobox, there was little manufacturing capability for a unibody design in the Ford system.

The engineers at Ford had to compromise and improvise at every stage of their design, still, they did a decent, if not stellar job, and if it weren’t for that one tiny design flaw (a pesky tendency for the gas tank to rupture against a frame piece in rear impacts) the Pinto would have been remembered as a practical, if eminently forgettable, econobox.

(Sorry for the rant, I always feel the need to defend otherwise good engineers who are forced to produce crap)

But anyhow, you’re totally missing the point, Donald.

This is nothing more than another version of the old “God wouldn’t have done it that way” argument … There simply is no scientific basis to say that sub-optimal design equals no design.

Bull pookey.

Reverse-engineer any manufactured product and you can learn a lot about the capabilities and methods of the designer.

Anybody who’s handled, for example, western and Asian machine tools, can tell just by the different materials that China hasn’t had a good steelmaking infrastructure as long as Germany has.

A cash register full of precision mechanical parts probably came from an older, established company, which has interest in amortizing an existing assembly line, while an equivalent product full of fast microcontrollers probably comes from a new player, which has to bite the bullet on NRE anyhow, so they optimize unit-cost.

Howard Hughes built the famous Spruce Goose out of a very sub-optimal material. Even without knowing about WW-II you could surmise that he was probably facing some sort of supply problem with aluminum.

Reverse-engineer the Pinto, compare it to the Civic, and you can see exactly what technology the two builders did and didn’t share.

It’s perfectly scientific. It’s all cause-and-effect. Down here on Earth that’s the way we have to do things.

Yes, the Pinto was a flawed design — because it was built by mortal engineers. Engineers working with all sorts of arbitrary, earthly, constraints.

You can tell something about those constraints just by carefully examining the design.

But all-knowing, all-seeing, all-powerful God - a God who made all the physical laws of the universe in the first place - just plain doesn’t have those limits.

There’s just no reason for God to compromise. God should be able to make a perfect product — He controls all the rules.

He is, in fact, not only the only engineer in the known universe who has the opportunity to do a perfect design — he’s actually got the easiest time of it.

So if, as you propose, Donald, He still consistently borrows inappropriate parts from previous designs and does a slap-dash modification to repurpose them into another sub-optimal design, there are only two good explanations.

1) God is not all knowing/seeing/powerful or… 2) God is incompetent.

This is a fascinating new line of reasoning you have there, Don. Which option do you favor?

Vertebrates do very well with the limitations of the design of the eye, but it is clear that this is no system a competent designer would make.

The same can be said about the Ford Pinto, but no one would claim that it wasn’t designed.

You think it might have been Ford Pinto designers who designed the eye?

What you anti-science sorts fail to recognize is that you have an idiot savant designer, who can design what humans can’t hope to design de novo (flagellum as it exists in all of its complexity–or the eye, which often is an example of what “couldn’t evolve”), yet can’t think well enough to put the blood vessels behind the retina. Or, he can think to do it, but not in vertebrates.

Which leads to the next failing of your “thought”. We have good explanations for “poor design”, indeed, we know why designs are often poor. It is because evolution produces little novelty and it cannot “see ahead” to design anything from scratch. Hence the “poor design” that we fits into evolutionary constraints (archaeopteryx is not simply “poorly designed” compared with modern birds, it is “poorly designed” because it was adapted from a small theropod dinosaur. You have no explanation at all), and above all, “poor design” follows the well-established patterns of inheritance.

We can tell you why sperm whales have the “poor design”, then, when the giant squids that it eats have the better “designs”—the reason being that whales are come from a lineage constrained by evolutionary events that gave it a poorer “design”, and squids are not. Why don’t you explain why marine mammals have one “design” and squids have quite another one? If evolution doesn’t explain it, there is no explanation, the only outcome with which IDists and creationists are satisfied.

This is nothing more than another version of the old “God wouldn’t have done it that way” argument, which raises the question of what is a theological premise doing in what is supposed to be a scientific argument?

Yes, why do you claim that design is a scientific argument when you steadfastly refuse to posit a designer producing predictable results? I’m glad you’re seeing the problem at last.

Perhaps there is some new scientific reasearch studies that comfirm an hypothesis about what God would or would not have done? If no such studies exist (and surely they don’t), then claiming that the supposed “sup-optimal’ design of this or that biolgical system demonstrates there was no design at all is little more than hand waving speculation.

Tell that to Dembski, who tries to tell us what is expected from God. Indeed, it is mere speculation, our point exactly.

There simply is no scientific basis to say that sub-optimal design equals no design.

Actually, it isn’t optimality that shows design, it is rational design, novelty, and borrowing good ideas from disparate sources, that indicates design by known designers. It is only because IDists/creationists frequently claim that “design” is “too good to have evolved” that we point to the many examples of “poor design” to show how false your claims are, even by your own standards. Nevertheless, optimized “designs” are presumably possible via evolution, as well as through design proper.

The trouble for you is that both “very good designs” and “poor designs” happen to betray their derivative origins, to fulfill the predictions of evolution. We have good explanations (generally, if not always) both for the “good designs” that we see, and the “poor designs”. All you have is the ridiculous plaint that “we don’t know how God would design”. That may be, however we do know how evolution would “design”, and it is essentially as we observe in organisms, in cladistics, in the derivative structures seen throughout life.

Once again the metaphysical presuppositions overshadow the science. When will you guys admit it.

We do admit that your metaphysical presuppositions overshadow what you call “science”, which is without any meaningful predictions (sorry, complexity beyond the capability of known designers is not a prediction of design, rather it is an indication of non-design).

We sometimes do take the word of IDists at face value, however, and ask if any marks of design exist in organisms. When we do not find them, the “obviousness” of design in organisms is no longer evoked by the true believers, rather the invisibility of design (since we don’t know what it looks like when God does it) becomes your argument. And yes, thanks for finally admitting our primary objection against ID, that no evidence for it exists.

Glen D http://tinyurl.com/b8ykm

“Seems to me that ID making any statement that anything was ‘designed’ or ‘designed well’ (which happens routinely) is a metaphysical presupposition that overshadows science.”

But, but, but… ID doesn’t make a claim about WHO the “designer” is or His intentions, it just says that we can detect His “design!”

“There simply is no scientific basis to say that sub-optimal design equals no design.”

Evolution works with what it has, which is why we would expect to find flaws like this or vestigial structures. On the other hand, it seems a “designer” wouldn’t leave these in the design. I find that people resort to these “science can’t make claims about the metaphysical” or what have you when they don’t like the implications of the evidence.

[Some cephalopods] see polarized light (which vertebrates can’t).

Actually, most humans can, especially with practice.

I find that I’m sensitive to polarized light out at the very outer edge of my visual field.

It manifests itself when I’m sitting in my car on a bright day, looking ahead, and I can detect moiré patterns in the glass of the drivers-side window, just at the edge of my peripheral vision (which instantly go away if I turn my central vision onto them).

It took me a while to work it out, but with a little experimentation, I eventually I figured out that the pinpoint source of the sun and oblique angle combined with the multi-layered safety glass to make a primitive polarizing filter with significant banding.

Oddly, I’m also much more sensitive to flicker out at the extreme edges, too.

[Some cephalopods] see polarized light (which vertebrates can’t).

Actually, most humans can, especially with practice.

I find that I’m sensitive to polarized light out at the very outer edge of my visual field.

It manifests itself when I’m sitting in my car on a bright day, looking ahead, and I can detect moiré patterns in the glass of the drivers-side window, just at the edge of my peripheral vision (which instantly go away if I turn my central vision onto them).

It took me a while to work it out, but with a little experimentation, I eventually I figured out that the pinpoint source of the sun and oblique angle combined with the multi-layered safety glass to make a primitive polarizing filter with significant banding.

Oddly, I’m also much more sensitive to flicker out at the extreme edges, too.

[Some cephalopods] see polarized light (which vertebrates can’t).

Actually, most humans can, especially with practice.

I find that I’m sensitive to polarized light out at the very outer edge of my visual field.

It manifests itself when I’m sitting in my car on a bright day, looking ahead, and I can detect moiré patterns in the glass of the drivers-side window, just at the edge of my peripheral vision (which instantly go away if I turn my central vision onto them).

It took me a while to work it out, but with a little experimentation, I eventually I figured out that the pinpoint source of the sun and oblique angle combined with the multi-layered safety glass to make a primitive polarizing filter with significant banding.

Oddly, I’m also much more sensitive to flicker out at the extreme edges, too.

Cue Lenny, and his usual post about DonaldM’s monthly drive-by lie.

Let’s see if there’s anything to say in response to Donald not covered by stevaroni …

*thinks*

*thinks*

Hmm… the answer seems to be no. Well, I’ve never let that stop me.

Donald M Wrote:

The same can be said about the Ford Pinto, but no one would claim that it wasn’t designed.

Yes, clearly the Ford Pinto was designed by a loving, caring, omnipotent deity. He loved his children so much he wanted them to be BURNED! Hail and Amen!

I think we can safely conclude that the Ford Pinto was not designed by the Christian God. Do you conclude this as well, Donald? Or do you feel that we must remain agnostic regarding whether Ford Pintos are examples of divine miracles?

Donald M Wrote:

This is nothing more than another version of the old “God wouldn’t have done it that way” argument, which raises the question of what is a theological premise doing in what is supposed to be a scientific argument?

Theological premises derived from the Bible:

1. God is perfect. 2. God loves us. 3. God cares about us. 4. God is competent at design (as an omnipotent being must be in all things)

Conclusion: The God of the Bible did not directly create the eye.

Please inform me which of the premises is false.

Donald M Wrote:

Perhaps there is some new scientific reasearch studies that comfirm an hypothesis about what God would or would not have done?

I’m talking theology! God was already outside of scientific discourse. Theologically, it is heresy to attribute anything so cocked up as the human eye to God.

Donald M Wrote:

If no such studies exist (and surely they don’t), then claiming that the supposed “sup-optimal’ design of this or that biolgical system

See, this is your goof. The design isn’t “sub-optimal”. The design is plain dog stupid. Attributing plain dog stupid design to God is an insult to my religion.

Donald M Wrote:

demonstrates there was no design at all is little more than hand waving speculation.

Who said there is no design? We said there is no intelligent design. And the design is stupid! It matches exactly what we expect from everyone’s favorite unintelligent designer: evolution by natural selection.

How is it that Behe produced some pretty good science back in the day in regards to biochemistry in his research, yet can’t seem to understand the very basics of biology, including biochemsistry, and is so off on biological reality? I mean, seriously, it’s never made sence to me.

I’ve heard repeatedly that Denton left the DI and pretty much repudiated the crap he used to write, but I haven’t been able to find a source for this claim.

Anyone have a link?

Well, Denton’s status as erstwhile Fellow of the Disco Inst is evident from Disco Inst’s own website. He seems to have become a sort of “nonperson” over there. Of course, Johnson, Behe, Wells, etc. can’t unpublish the remarks they’ve all made about how Denton’s “Evolution: a Theory in Crisis” opened their eyes to the “failures of Darwinism”, but in fact that book was all about challenging common descent. In Denton’s 2000(? or so) book, “Nature’s Destiny”, he drops that whole line altogether, and makes a pitch for a whole different proposition: “cosmological intelligent design”.

The piece Witt is resurrecting here is from 1999, when Denton and the Disco Inst were, apparently, still on speaking terms. If I recall correctly - and I refuse to waste the precious five minutes of my life it would take to reread and confirm this - Denton makes the case that the fact that the weird vertebrate eye evolved in our fishy ancestors argues that the Intelligent Designer was anticipating the eventual benefits of such an arrangement in their eventual warm-blooded, terrestrial descendants.

Pretty hilarious stuff.

Donald M: Perhaps there is some new scientific reasearch studies that comfirm an hypothesis about what God would or would not have done? If no such studies exist (and surely they don’t),

You’re right. Scientific studies couldn’t show that. But there are good theological studies to indicate that the IDea of God creating systems that don’t work is a pretty poor understanding of God- at least the Judeo-Christian God. There are some good theolgical thoughts on how we can actually understand the Judeo-Christian God. Maybe though you’re coming from a different kind of god then that, in which case understanding god may not be important or possible, and god may not be perfect.

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The folks here are probably already aware of this, but AIG’s Dr David Menton ( very similar sounding name !) has a couple of talks on the origins of the eye :

http://www.answersingenesis.org/video/ondemand/

He makes the claim that at least one evolutionist has admitted that we don’t know the evolutionary origins of the eye and that we probably never will.

Russell brings up that: Well, Denton’s status as erstwhile Fellow of the Disco Inst is evident from Disco Inst’s own website. He seems to have become a sort of “nonperson” over there. Of course, Johnson, Behe, Wells, etc. can’t unpublish the remarks they’ve all made about how Denton’s “Evolution: a Theory in Crisis” opened their eyes to the “failures of Darwinism”, but in fact that book was all about challenging common descent. In Denton’s 2000(? or so) book, “Nature’s Destiny”, he drops that whole line altogether, and makes a pitch for a whole different proposition: “cosmological intelligent design”.

It seems to me ironic the similtude between the Creationist groups diversity and disagreements, well described in Pennock’s “Tower of Babel”, and that of the early Gnostics. In both the infighting would lead ultimately to being sidelined and ultimately being irrelevant.

Steveroni

Au Contraire, Donald.

The Ford Pinto was actually a pretty reasonable design at the time, given the prevailing constraints the engineers were working with. …snip… The engineers at Ford had to compromise and improvise at every stage of their design, still, they did a decent, if not stellar job, and if it weren’t for that one tiny design flaw (a pesky tendency for the gas tank to rupture against a frame piece in rear impacts) the Pinto would have been remembered as a practical, if eminently forgettable, econobox.

Okay fine. So, given that the vertabrate eye does a decent if not stellar job, how does its supposed sub-optimal design equate to no design at all? Its easy to play arm chair designer and imagine all sorts of improvements in one component part of a given system, but as you just pointed out real designers seek to acheive constrained optimism where each sub-system contributes to the best over-all function of the entire system.

But all of that is beside the point. The one and only point is that there is no scientifically principaled way to equate sub-optimal design with no design at all. That is based entirely on a metaphysical premise somewhere in the neighborhood of “God wouldn’t have done it that way.”

There’s just no reason for God to compromise. God should be able to make a perfect product — He controls all the rules.

Perfect with respect to what overall purpose? Statements like this are simply fraught with huge theological premises. That’s fine, but what are those premises doing in what’s supposed to be a scientific argument? The claim is still ‘sub-optimal design equals no design.’ That is not a scientific statement.

Arden Chatfield

Seems to me that ID making any statement that anything was ‘designed’ or ‘designed well’ (which happens routinely) is a metaphysical presupposition that overshadows science. When when you guys admit that?

I don’t see how that follows. It is a purely legitimate scientific observation to say that chance and necessesity or their combination lack the resources to account for the level of specified complexity observed in some system X and that X bears all the hallmarks normally associated with things that are acutally designed. There’s nothing metaphysical about that. It is a farily straightforward scientific observation. Now, it might be incorrect, or disconfirmed by other evidence, but that is a different matter altogether. What it is not is metaphysical. What is entirely metaphysical is to say that the properties of the cosmos are such that any apparent design we observe in biological systems can not be actual design, even in principal, which is the claim made by anti-IDists all the time. In other words, ruling out design a priori on metaphysical grounds.

Coin

Okay, so Donald, be clear here. Do you agree then that it is not logically possible to identify a “designed” from a “non-designed” object without specific knowledge of the designer in question?

Of course I don’t agree. SETI being a case in point. If it were the case that a signal from space were discovered such as the one in the movie Contact and was attibuted to intelligent cause, we still wouldn’t have any specific knowledge of the designer(s) in question. But again, all this is really beside the point, which is, quite simply, that to say sub-optimal design equals no design is metaphysical and not scientific.

While we are on the subject of the eye, why did our designer limit us to just 3 color-sensitive pigments while giving goldfish 4, some birds 5, and some random arthropod like the mantis shrimp 16? How come fish that live under water, which has high UV absorbance relative to air, have UV vision while we don’t? Why would a creature like humans that are “designed” to live on the ground in a savanna (or garden) be given a point fovea that can only see straight ahead instead of a linear fovea that can see the entire horizon like some other savanna-dwelling mammals have? How come we are designed so that our eyes will automatically hide from us the fact that we are going irreversible blind from easily-correctable causes? Why do fish fish, amphibians, and reptiles have lenses that move around in the eye to change focus while mammals and birds have ones that change shape and thus harder over time, forcing us to use get glasses when we get older?

But again, all this is really beside the point, which is, quite simply, that to say sub-optimal design equals no design is metaphysical and not scientific.

Then why is saying “[apparent] optimal design equals design” not metaphysical?

What I find particularly revealing is that the Yamamoto et al paper was published in 1965. And the descriptive title, “Fine Structure of the Octopus Retina,” would have made it easy to find even before the advent of searchable electronic databases. Yet even a glance at Fig. 1 utterly destroys Denton’s arguments–the extensive vascularization is quite apparent, as is the presence of pigment to prevent light scattering. It is even possible to see how support cells are incorporated without interfering with photoreceptor packing–all supposed problems with the “verted” design according to Denton. So did he really not bother to even look up the anatomy of the octopus eye before pontificating? Or is he simply lying, expecting that most of his audience will never bother to look it up (in which assumption, he was apparently correct, as ID/creationists continue to cite it to this day).

Okay, so Donald, be clear here. Do you agree then that it is not logically possible to identify a “designed” from a “non-designed” object without specific knowledge of the designer in question?

Of course I don’t agree… But again, all this is really beside the point, which is, quite simply, that to say sub-optimal design equals no design is metaphysical and not scientific.

So “sub-optimal design” is metaphysical, but “design” isn’t?

Why? What’s the difference?

SETI being a case in point. If it were the case that a signal from space were discovered such as the one in the movie Contact and was attibuted to intelligent cause, we still wouldn’t have any specific knowledge of the designer(s) in question.

Contact is a fictional movie, not real life.

In real life, SETI starts out assuming they know something about the “designers” they are hoping to find signals from. They assume that these designers are living beings who exist within the naturalistic universe, and that their signals are created by electromagnetic communication devices. They use this assumed knowledge about their “designers”, in fact, to discern whether the signals are designed at all; they aren’t testing for “design” by itself, they’re testing for signs of a specific “designer”. If SETI received a strange signal, they would immediately check to see whether that signal fits with the origin hypothesis of their assumed known designer. If the signal didn’t fit what they’d expect of the designers they’re expecting, they would probably start looking for hypotheses involving natural origins of the same signal. Consider the discovery of the LGM-1 signal, which, unlike “Contact”, actually happened in real life.

But even aside from this, you can absolutely bet that if we received a signal that, for whatever reason, we “attibuted” to intelligent life, the very first thing we would do is start speculating and drawing conclusions about the designers. We would in fact use the signal itself to learn about the designers. We would consider the place in the universe where the signal is identified of coming from (say, what kind of planets or other objects are visible there) to draw conclusions about what kind of life the signal might have come from, we would analyze the signal itself to draw conclusions about their signal transmission technology, we would analyze the signal’s content (if any) in every way we could think of…

But you’re telling us the opposite of what SETI does– you’re telling us we can identify “design” without having a specific designer in mind, but we can’t then use the design once identified to draw conclusions about the nature of the designer, since that would be “metaphysical”.

So, I continue to ask what is a theological premise doing in what’s supposed to be a purely scientific argument?

You tell us – YOU are the one who keeps yammering about “godless atheistic materialistic naturalistic science” . …

(shrug)

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Evolutionary[sic] doesn’t “predict” sub-optimal design.

leaving the “design” aspect of it aside for a moment (yes, I realize you are mentally incapable of leaving teleological perceptions aside), you could very easily have many predicted situations where the selective pressues on any given trait would result in something sub-optimal from an absolute fitness perspective.

-the trait might be genetically linked to one that had an even higher fitness value for the given set of selective pressures

-the trait might be balanced against competing traits (think “prisoner’s dillemma), hawks and doves, what have you.

-the current perceived regime of selective pressures might not be the ones that were important in the evolution of the trait to begin with, this is especially true in the case of the vertebrate eye.

as usual, ducky hasn’t a clue what he’s on about.

shocker.

My friends: I was referred in here from a vastly different thread & discussion. The comments by Donald M are hilarious. The scientists herein attempt to write in logical, factual prose; Donald M pontificates. The rules of logic apply absolutely in math, philosophy, etc.; not so much elsewhere.

In the truly olden days, Aquinas & Augustine attempted to define religious beliefs in forms of Aristotelian logic. Then along came Calvin & Wesley & the arguments fell apart because everything they BELIEVED is illogical. The main reason religious arguments are gavelled out of the courtrooms is that the rules of law require logic. Theology ignores & transcends logic.

One of the difficulties with the life sciences may be that not all of those various bodies of knowledge are logical. As a result, verbally skilled fools can use third-rate rhetorical devices to advance illogical fallacies about evolution because the scientific disciplines most concerned with the topic have some genuninely illogical stuff to work with–such as variations among cephalod eyes & the vertebrate eyes, wow. The rhetoric, then, convinces a few silly people that the science is questionable and, if not absolute, then wrong.

Most of the posters here simply blow Donald M out of the discussion: if his particular deity has any of the attributes commonly assigned to that entity, then the evidence here on this planet contradicts the presence of all those attributes in the design, creation & production of “stuff,” & the evidence in space just laughably refutes every possible attribute of that deity.

Finally, Aristotle attempted to sort out some of these issues. In Latin, scientia means knowledge; but the word also describes specific disciplines of knowledge. Thus the differences between “meta ta physika,” “scientia” & “scientia de ente.” There is an immense difference between discussing a being & BEING [de rerum natura & metaphysica].

Anyway, for those of you who “feel” that Donald M appears to be an intelligent person, he merely shows a rhetorical skill common to preachers, used car salespersons & politicians–nothing really there except clouds of murky chop logic, false premises (or promises) & faint hopes that their beliefs resemble some aspects of the facts. And his assertion that the discussion refers to metaphysics is a misuse of that term. Theology, his, & actual metaphysics are infinitely different (pun intended).

Donald Dissembled: But, at least we agree that the claim that sub-optimal design equals no design isn’t scientific, which was my only point all along.

You intellectual dishonesty is showing Don. It’s been explained quite clearly to you several times that it is moronic, idiotic, downright foolish design that is at issue, and which disproves design by an omnipotent being.

Coin — That was most wondrously done! Thank you for the clear, crisp prose…

and so the argument is intended to say sub-optimal design proves no design and therefore neither God nor any other intelligent agent was involved in bringing this system into existence.

well, ducky, all you have to do is show us exactly what the characteristics of “the designer” are, and then you can quickly go about logically rejecting hypotheses that don’t fit what your proposed designer might have done or not done, eh?

but neither you, nor anybody else, can tell us what those characteristics really are.

gee, I wonder why that is…

‘Rev Dr’ Lenny Flank posted:

“It’s why they have already lsot every single Federal court case they have ever been involved with. Every single one.”

Creationists have lost in court in the past because judges deal with the facts of the case and the constitution. Conservatives understand this is a problem for them. They are trying to fill the judiciary with activist judges who will rule according to conservative ideology. The creationists’ courtroom losing streak is not guaranteed to continue.

Its not enough to explain DonaldM’s logical fallacies, its not even enough to make the DonaldMs of the world look like fools. The goal is to keep the creationists and their political leaders out of power. Making the DonaldMs look stupid is only useful as a means to that end.

They are trying to fill the judiciary with activist judges who will rule according to conservative ideology.

Like Judge Jones … ? (snicker) (giggle)

The creationists’ courtroom losing streak is not guaranteed to continue.

Oh yes it will. The Republicrat power structure doesn’t want the fundies to gain real power, any more than anyone else does. They just use the fundies to gain votes and money. Even Bush’s Supreme Court refused to reconsider the Freiler case (which the fundies lost). Heck, Bush’s Supreme Court won’t even go along with him on, ya know, detaining people indefinitely without trial.

The goal is to keep the creationists and their political leaders out of power.

Alas for them, the last election seems to have done a pretty effective job of that for a few years. (snicker) (giggle)

thanks all, i am progressively learning all that i have missed while holding strictly to Christian dogma over the years, which was a result of my upbringing. after coming to realize the many instances of contradiction and injustice in the Bible, i finally came to reject it as “divinely inspired,” and have since been exploring science and philosophy openmindedly. a great site on the above which helped break me out of my bias is http://skepticsannotatedbible.com/

also, the book “Misquoting Jesus,” by Bart Ehrman has helped me a great deal.

i would like to ask your advice as to what materials i should read now, and in particuar as regards science/ evolution. thanks again!

Alas for them, the last election seems to have done a pretty effective job of that for a few years. (snicker) (giggle)

so has a predilection for gay sex, pedophillia, and drugs, apparently.

that was some week before the elections, eh?

i would like to ask your advice as to what materials i should read now, and in particuar as regards science/ evolution. thanks again!

easy. check the links to good references on the subject on the front page of this very site.

evolution simply “predicts” whatever turns up.

Sigh. OK, once more, slowly.

Evolution predicts that nature will use whatever turns up, and good ideas that help organisms survive will be kept. Some will be optimal, some less so. The vast majority of mutations will be bad, but because they harm the creature, they will be lost. Some of the rest will be useful, and will be kept, most will be neutral and ride along. Some will be a little bad, but tolerated because they come with some benefit (think sickle-cell trait, which causes anemia, but protects against malaria).

ID predicts that evidence of design will be found. Design, at least design carried out by an all-knowing, all-seeing, all-powerful God, can be reasonably assumed to be free of large numbers of sub-optimal, even harmful kluges. If the creator is a loving (and technically capable) God, making us in his own image, there’s simply no good reason why we have things like a reproductive system that allows large numbers of kids to be born with fatal birth defects.

i would like to ask your advice as to what materials i should read now, and in particuar as regards science/ evolution.

Anything by Dawkins.

Anything by Gould.

Mayr’s “What Evolution Is”.

Kenneth Miller’s “Finding Darwin’s God”.

John Shelby Spong’s “Rescuing the Bible from Fundamentalism” is a bit old, but still good.

so has a predilection for gay sex, pedophillia, and drugs, apparently.

Oh heck, they’ve ALWAYS had THAT.

;)

that was some week before the elections, eh?

I suspect much of it was release-timed. If so, perhaps the Democans have grown themselves a pair after all (although it was the rank-and-file Democans who won this election – the leadership was all set, as usual, to roll over and play dead).

Am I the only one to notice the similarity and in sentence structure, argument selection and phraseology between Donald’s posts here, and CSC posts attributed to Casey Luskin? (check http://www.evolutionnews.org/2006/1[…]olution.html for example)

Am I the only one to notice the similarity and in sentence structure, argument selection and phraseology between Donald’s posts here, and CSC posts attributed to Casey Luskin?

Donald has ALWAYS simply parroted whatever he’s told.

When he was in the DebunkCreation email list, 8-9 years ago, he faithfully parroted all the standard YEC arguments, right up until ID became the new political game in town — when he promptly switched horses and began faithfully parroting page after page from Behe’s book instead.

He hasn’t stopped parroting since. And indeed, he’s been preaching the very same “atheistic science unfairly rules out the supernatural boo hoo hoo!!” sermon for five or six years now.

Like all creationists, he’s utterly incapable of original thought. (shrug)

Folks,

Despite all the vitriolic garbage that has been heaped upon him here by folks who claim to be rational, the fact is that Donald M’s main point, as I understand it, is absolutely correct and any skull with a modicum of gray matter under it should find it obviously so. And that point is, as I would formulate it:

In the absence of any knowledge of a possible deigner’s motives, goals, purposes and methods, we cannot use the fact that the eye’s structure seems to us, from the point of view of OUR goals and purposes, to be sub-optimal, as an argument for there being no designer.

This is indisputably logical. Now why cannot some “intelligent” folks here understand this idea?

In the absence of any knowledge of a possible deigner’s motives, goals, purposes and methods,

except that wasn’t HIS point, Carol.

Donald wanted to simply make an exception for his God, without defining that God to begin with.

THAT was his point.

you misninterpreted it because you assumed ducky is logical to begin with.

that was your error.

beyond that…is your god not omnipotent and omniscent, Carol?

do tell us your analyis of the Hebrew God’s characteristics, so we can all logically reject arguments based on the most common assumptions on the nature of God, eh?

phht.

…and while you’re at it, oh dense one, do note that the thread contribution is about refuting the ridiculous postulates of CREATIONISTS IN FAVOR OF DESIGN, not vice versa. Or didn’t you even bother to read Ian’s post?

ID advocates have a hard time dealing with the quirky design of the eye, both Witt and Behe have used the “better blood flow” argument in order to show the backwards retina really is good design.

This invokes an argument that has been doing the rounds of creationists for a while. The True.Origins site (which is a rip-off of Talk.Origins) has a page that claims that the “backwards” retina improves the blood supply. It is probably the canonical page where these claims come from. Denton’s argument is slightly different, but follows on from the canonical creationist argument, so I will deal with the creationist argument first.

it’s not the scientists argument that bad design disproves god, it’s the creobot’s argument that twisting the appearence of design to “make it look good” proves it is good design, and therefore: Goddidit.

*sigh*

will you never get past your own dissonance?

go save some zebras or something, eh?

Or, Carol, putting it another way, how sub-optimally, non-optimally, or a-optimally “designed” can something be and still be meaningfully called “designed.”

Especially, as STJ notes, in the absence of anyone with the guts to commit to identify some usefully-forensic characteristics regarding the “designer”?

We know one well-evidenced method by which “apparent” design is generated in living forms: evolution.

And then we have these fuzzy, evidence-free claims that there’s some other way to do it…

Until a serious problem is demonstrated for evolution, or some serious evidence is adduced for the fuzzy claims that currently lack any, it’s more than a little silly to hold out hope for the success of the latter over the former.

Hi. If a non-biologist could ask a question. Might it be the case that the choroid itself is the original organ, that ot developed as a heat sensor, and from there became part of a light detection complex ?

Eoin

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This page contains a single entry by Ian Musgrave published on November 14, 2006 6:24 AM.

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