…and this is a 
Jonathan Sarfati, a particularly silly creationist, is quite thrilled — he's crowing about how he has caught Richard Dawkins in a fundamental error. The eye did not evolve, says Sarfati, because it is perfectly designed for its function, and Dawkins' suggestion that there might be something imperfect about it is wrong, wrong, wrong. He quotes Dawkins on the eye.
But I haven't mentioned the most glaring example of imperfection in the optics. The retina is back to front.
Imagine a latter-day Helmholtz presented by an engineer with a digital camera, with its screen of tiny photocells, set up to capture images projected directly on to the surface of the screen. That makes good sense, and obviously each photocell has a wire connecting it to a computing device of some kind where images are collated. Makes sense again. Helmholtz wouldn't send it back.
But now, suppose I tell you that the eye's 'photocells' are pointing backwards, away from the scene being looked at. The 'wires' connecting the photocells to the brain run over all the surface of the retina, so the light rays have to pass through a carpet of massed wires before they hit the photocells. That doesn't make sense…
What Dawkins wrote is quite correct, and nowhere in his refutation does Sarfati show that he is wrong. Instead, Sarfati bumbles about to argue against an argument that no biologist makes, that the eye is a poor instrument for detecting patterns of light. The argument is never that eyes do their job poorly; it's that they do their job well, by a peculiar pattern of kludgy patches to increase functionality that bear all the hallmarks of a long accumulation of refinements. Sarfati is actually supporting the evolutionary story by summarizing a long collection of compromises and odd fixes to improve the functionality of the eye.
There's a fundamental question here: why does the vertebrate eye have its receptors facing backwards in the first place? It is not the best arrangement optically; Sarfati is stretching the facts to claim that God designed it that way because it was superior. It ain't. The reason lies in the way our eye is formed, as an outpocketing of the cortex of the brain. It retains the layered structure of the cortex, even; it's the way it is because of how it was assembled, not because its origins are rooted in optical optimality. You might argue that it's based on a developmental optimum, that this was the easiest, simplest way to turn a light-sensitive patch into a cup-shaped retina.
Evolution has subsequently shaped this patch of tissue for better acuity and sensitivity in certain lineages. That, as I said, is a product of compromises, not pre-planned design. Sarfati brings up a series of odd tweaks that make my case for me.
The vertebrate photoreceptors are nourished and protected by an opaque layer called the retinal pigmented epithelium (RPE). Obviously, you couldn't put the RPE in front of the visual receptors, so the retina had to be reversed to allow it to work. This is a beautiful example of compromise: physiology is improved at the expense of optical clarity. This is exactly what the biologists have been saying! Vertebrates have made a trade-off of better nutrient supplies to the retina for a slight loss of optical clarity.
Sarfati makes the completely nonsensical claim that the presence of blood vessels, cells, etc. in the light path do not compromise vision at all because resolution is limited by diffraction at the pupil, so "improvements of the retina would make no difference to the eye's performance". This is clearly not true. The fovea of the vertebrate eye represents an optimization of a small spot on the retina for better optical properties vs. poorer circulation: blood vessels are excluded from the fovea, which also has a greater density of photoreceptors. Obviously, improvements to the retina do make a difference.
It's also not a condition that is universal in all vertebrates. Most birds, for instance, do not have a vascularized retina — there is no snaky pattern of blood vessels wending their way across the photoreceptors. Birds do have greater acuity than we do, as well. What birds have instead is a strange structure inside their eye called the pecten oculi, which looks kind of like an old steam radiator dangling into the vitreous humor, which seems to be a metabolic specialization to secrete oxygen and nutrients into the vitreous to supply by diffusion the retina.
Sarfati also plays rhetorical games. This is a subtly dishonest argument:
In fact, cephalopods don't see as well as humans, e.g. no colour vision, and the octopus eye structure is totally different and much simpler. It's more like 'a compound eye with a single lens'.
First, there's a stereotype he's playing to: he's trying to set up a hierarchy of superior vision, and he wants our god-designed eyes at the top, so he tells us that most cephalopods have poorer vision than we do. He doesn't bother to mention that humans don't have particularly good vision ourselves; birds have better eyes. So, is God avian?
That business about the cephalopod being like a compound eye is BS; if it's got a single lens, it isn't a compound eye, now is it? It's also again pandering to a bias that our eyes must be better than mere compound eyes, since bugs and other lowly vermin have those. Cephalopods have rhabdomeric eyes, meaning that their photoreceptors have a particular structure and use a particular set of biomolecules in signal transduction, but that does not in any way imply that they are inferior. In fact, they have some superior properties: the cephalopod retina is tightly organized and patterned, with individual rhabdomeres ganged together into units called rhabdomes that work together to process light. Their ordered structure means that cephalopods can detect the polarity of light, something we can't do at all. This is a different kind of complexity, not a lesser one. They can't see color, which is true, but we can't sense the plane of polarity of light in our environment.
I must also note that the functions of acting as a light guide (more below) and using pigment to shield photoreceptors are also present in the cephalopod eye…only by shifting pigments in supporting cells that surround the rhabdome, rather than in a solid RPE. Same functions, different solutions, the cephalopod has merely stumbled across a solution that does not simultaneously impede the passage of light.
Color vision, by the way, is a red herring here. Color is another compromise that has nothing to do with the optical properties of the arrangement of the retina, but is instead a consequence of biochemical properties of the photoreceptors and deeper processing in the brain. If anything, color vision reduces resolution (because individual photoreceptors are tuned to different wavelengths) and always reduces sensitivity (you don't use color receptors at night, you may have noticed, relying instead on rods that are far less specific about wavelength). But if he insists, many teleosts have a greater diversity of photopigments and can see colors we can't even imagine…so humans are once again also-rans in the color vision department.
Sarfati is much taken with the discovery that some of the glial cells of the eye, the Müller cells, act as light guides to help pipe light through the tangle of retinal processing cells direct to the photoreceptors. This is a wonderful innovation, and it is entirely true that in principle this could improve the sensitivity of the photoreceptors. But again, this would not perturb any biologist at all — this is what we expect from evolution, the addition of new features to overcome shortcomings of original organization. If we had a camera that clumsily had the non-optical parts interposed between the lens and the light sensor, we might be impressed with the blind, clumsy intricacy of a solution that involved using an array of fiber optics to shunt light around the opaque junk, but it wouldn't suggest that the original design was particularly good. It would indicate short-term, problem-by-problem debugging rather than clean long-term planning.
Sarfati cannot comprehend why the blind spot would be a sign of poor design, either. He repeats himself: why, it's because the eye needs a blood supply. Yes, it does, and the solution implemented in our eyes is one that compromises resolution. I will again point out that the cephalopod retina also needs a blood supply, and they have a much more elegant solution; the avian eye also needs a blood supply, but is not invested with blood vessels. He gets very circular here. The argument is not that the vertebrate eye lacks a solution to this problem, but that there are many different ways to solve the problem of organizing the retina with its multiple demands, and that the vertebrate eye was clearly not made by assembling the very best solutions.
Sarfati really needs to crawl out of his little sealed box of creationist dogma and discover what scientists actually say about these matters, and not impose his bizarre creationist interpretations on the words of people like Dawkins and Miller. What any comparative biologist can see by looking at eyes across multiple taxa is that they all work well enough for their particular functions, but they all also have clear signs of assembly by a historical process, like evolution and quite unlike creation, and that there is also evidence of shortcomings that have acquired workarounds, some of which are wonderfully and surprisingly useful. What we don't see are signs that the best solutions from each clade have been extracted and placed together in one creature at the pinnacle of creation. And in particular — and this has to be particularly grating to the Genesis-worshipping creationists of Sarfati's ilk, since he studiously avoids the issue — Homo sapiens is not standing alone at that pinnacle of visual excellence. We're kinda straggling partway down the peak, trying to compensate for some relics of our ancestry, like the fact that we're descended from nocturnal mammals that let the refinement of their vision slide for a hundred million years or thereabouts, while the birds kept on optimizing for daylight acuity and sensitivity.
Life Science
Comments
Posted by: MoonShark
|
June 7, 2010 12:40 PM
Dawkins and the human eye? Reminds me of this classic video.
Posted by: James F
|
June 7, 2010 12:48 PM
"trying to compensate for some relics of our ancestry"
Nicely put.
Posted by: NewEnglandBob
|
June 7, 2010 12:52 PM
The stupid, they keep on coming. Great knockout, PZ!
Posted by: Travis
|
June 7, 2010 12:55 PM
Great knock down of that. Pretty easy to do but that was thorough and detailed. Is this the best the people at Creation Ministries International can do? Pretty sad.
Posted by: Phodopus
|
June 7, 2010 12:58 PM
It is indicative of their very limited scope and insight into the subject that creationists always seem to think that Richard Dawkins is the pinnacle of evolutionary biology and his words its foundation, as if there weren't literally tens of thousands of biologists working in related fields doing all the original research. Nothing 'gainst RD, but that is just an epic failure concerning their grasp on how science works nowadays.
Posted by: darbyunlimited
|
June 7, 2010 12:59 PM
I'm a bit curious about the "no color detection" assumption for cephalopods. What's the underlying evidence?
Having seen video of cuttlefish and octopi seeming to match color with their camouflage, it SEEMS like they'd need to see color to match color...
Posted by: theshortearedowl
|
June 7, 2010 1:06 PM
Excellent: another excuse to bring up mantis shrimp.
12 colours, infrared and ultraviolet perception and polarised light. God must have been smoking something good that day.
Posted by: "Roger"
|
June 7, 2010 1:06 PM
Sarfati is dishonest. I remember one article he wrote about "vestigial organs":
Some evolutionists, like Dr Meiss, now want to re-define ‘vestigial’ to mean simply ‘reduced or altered in function’. Thus even valuable, functioning organs (consistent with design) might now be called ‘vestigial’. CMI isn’t going to let evolutionists change the rules at their whim when they are losing the argument.
Safarti's lie is exposed here (under the heading "vestiges can be functional")::
Third, regardless of popular misconception, from the beginning of modern evolutionary theory a complete absence of function has not been a requirement for vestigiality (Crapo 1985; Culver et al. 1995; Darwin 1872, pp. 601-609; Dodson 1960, p. 44; Griffiths 1992; McCabe 1912, p. 264; Merrell 1962, p. 101; Moody 1962, p. 40; Muller 2002; Naylor 1982; Strickberger 2000; Weismann 1886; Wiedersheim 1893, p. 2, p. 200, p. 205). Sarfati's claim is based upon ignorance, and he of course provides no historical references showing that evolutionary biologists actually changed the definition.
Intersting note: Safarti's article is no longer on the Answers in Genesis site, but is now on the Creation Ministries International site, where it's repeated the original AIG article (which TO repsonded to) verbatim, only AIG is replaced with CMI in the "updated" response.
Posted by: dynaboy
|
June 7, 2010 1:06 PM
If God can see everything everywhere, and God made us in His image, then why can I only see stuff that is right in front of me? Heck, I need corrective lenses just to see clearly more than a few inches away. Oh, and why do I have to turn my head before I can even change lanes? And why can't I get a zoom lens in my eyes to see far away things better, a la Steve Austin.
God is the Worst. Designer. Ever.
Posted by: Rev. BigDumbChimp
|
June 7, 2010 1:13 PM
No to mention that thumb shattering pneumatic hammer it carry's around
Why didn't god design me with something like that?
Posted by: tsg
|
June 7, 2010 1:14 PM
Yet more evidence that not only do they not know what they are arguing against, they have no desire to find out.
Posted by: SaraJ
|
June 7, 2010 1:16 PM
If the eye is so perfectly designed, why am I legally blind without my corrective lenses in? Why am I at high-risk for retinal detachment? I'd say it's because my parents passed on really crappy eye genetics to me, but maybe it really was just some silly creator with a crayon.
Posted by: Kraid
|
June 7, 2010 1:19 PM
To summarize:
Jonathan Sarfati -- FAIL
Posted by: circleh
|
June 7, 2010 1:22 PM
Plus, cephalopod eyes are wired FORWARDS, this debunking the claim by Dr George Marshall that eyes of vertebrates have a good reason to be wired backwards.
It doesn’t matter what you claim your scientific credentials to be; if you get caught lying to promote a false dogma, you should be publicly whipped over it.
Dale Husband, the Honorable Skeptic
Posted by: "Roger"
|
June 7, 2010 1:23 PM
Edit: In response to my (#8) comment: At least from what I remember, I think it was verbatim...it sure as hell is damned close if it isn't!
Posted by: Shala
|
June 7, 2010 1:23 PM
I guess you could say Sarfati was...
...blind to real science.
Posted by: Phodopus
|
June 7, 2010 1:27 PM
That his views lack ...
... scientific depth perception
Posted by: Rev. BigDumbChimp
|
June 7, 2010 1:27 PM
sigh
Posted by: Brownian, Most Vicious & Petty of Pharyngulites
|
June 7, 2010 1:28 PM
Why? Why would anything designed by an omniscient, omnipotent entity need anything? When I need to make something, I'm constrained by the tools at hand: wood, metal, clay, etc., but that's only because I can't wish whole universes into existence. An entity that could wouldn't be constrained by the need for any component of his or her creations.
Such an entity has no reason to be kludgey. Their creations should be perfect.
Unless of course, our blind-spots are purposely designed* so we can learn moral some-bullshit-or-other before we get into heaven, after which our heavenly eyes won't have optic nerves. Yay! Yay for Jesus!
*Could also be a consequence of the Fall, but I've been searching in vain for the line in Genesis where God warns Adam and Eve that as soon as they eat of the fruit of the tree of knowledge of good and evil he'll have to punch a hole in their backwards-facing retinas for the purpose of blood flow. So many consequences arising from one little fruit salad. No wonder Abrahamists don't have a clue about how causality works.
Posted by: Phodopus
|
June 7, 2010 1:30 PM
They're people out there who don't know how to use there apostrophes... Its a shame really.
Posted by: Hari Seldon
|
June 7, 2010 1:32 PM
darbyunlimited (#6) - You can tell what colors an organism can see by looking at either the photo-pigments (opsins) that are in the eye's photo-receptors, or by sequencing their DNA and seeing which opsins the DNA is capable of producing. There's an extensive discussion of this process in Sean Carrol's recent book "The Making of the Fittest". Having said that, I'm afraid that I don't know right offhand what the color vision of cephlapods is.
How the camouflage coloring works is another issue - I'm pretty sure it doesn't work via eyesight. There may be other cells that detect background color, but PZ would be a better person to discuss that (and he may have, at one time or another...)
Posted by: Phodopus
|
June 7, 2010 1:34 PM
Consider this:
http://scienceblogs.com/pharyngula/2007/06/cephalopod_camouflage_or_turni.php
Posted by: Glen Davidson
|
June 7, 2010 1:40 PM
I don't especially think the eye is a good example to bring up, especially since there are so many objections, and it works pretty well in spite of its evolutionarily-caused imperfections.
Transitionals, the iconic Archaeopteryx in particular, are better examples because they're especially "poor design" at a time when evolution expects such "poor design" -- and they're "bad design" quite obviously because of evolution.
Our eye is no doubt not anything like a "good design," but creationists can always complicate the story quite easily so as to gull their marks.
Glen Davidson
Posted by: James F
|
June 7, 2010 1:40 PM
Shala #15
Phodopus #17
YEAAAAAAAAAAHHHHH!!!!!!!!!!!!!
Posted by: Brownian, Most Vicious & Petty of Pharyngulites
|
June 7, 2010 1:41 PM
But sadly, they can't see the beauty of God's Creation around them...
[/apologetics]
Posted by: Techskeptic
|
June 7, 2010 1:42 PM
what kind of argument is this? this is beyond stupid.
Human eyes work incredibly shitty in the environments that an octopus lives in. As soon as human eyes drop 1 inch into water they see out of focus , highly distorted, images. An octopus sees just fine. Go down 50 feet and we are as colorblind as any other living thing on the planet, becuase those colors arent there!, why would an animal that lives in that environment have evolved something for which there is no opportunity to use it?
Posted by: Insightful Ape
|
June 7, 2010 1:45 PM
Blood vessels do not just block the light. They are inherently associated with the risk of infarction and permanent loss of vision. And in many conditions such as diabetes and retinal dystrophies they have a high risk of bleeding which can cause blindness. Clearly the "designer" liked the avians and Cephalopoda a lot better than us.
Incidentally since we were made in god's image, does it mean god's anatomy is as screwed up as ours?
Posted by: andrew h
|
June 7, 2010 1:48 PM
"you don't use color receptors at night, you may have noticed, relying instead on rods that are far less specific about wavelength"
not quite right; rods and cones have similar bandwidths (maybe rod spectral selectivity is a little broader, but not much), meaning that rods are basically just as specific for wavelength as cones. main difference is, there's just one type of rod, so specific wavelength can't be interpolated (i.e. wavelength is confounded with intensity) with a dark-adapted retina.
Posted by: natural cynic
|
June 7, 2010 1:53 PM
Posted by: Athena
|
June 7, 2010 1:55 PM
Maybe Rev.BDC needs eyes in his fingertips? *giggle*
Posted by: Rev. BigDumbChimp
|
June 7, 2010 1:59 PM
While that may help, I think slowing down and proofing every now and then would probably be just as effective.
Posted by: gillt
|
June 7, 2010 2:02 PM
PZ: "We're kinda straggling partway down the peak, trying to compensate for some relics of our ancestry, like the fact that we're descended from nocturnal mammals..."
Dammit all, then why don't I have cool reflector lenses like a jungle cat?!
Posted by: blf
|
June 7, 2010 2:04 PM
It/they did, but you use it to beat up the keyboard and commit typos.
Posted by: bernarda
|
June 7, 2010 2:09 PM
Animals before the Permian Extinction 250 million years ago had eyes. Why did god decide to exterminate nearly all species at that time?
Either animals with eyes managed to survive or the eye developed again.
Posted by: marcus
|
June 7, 2010 2:10 PM
Let me just say... mantis shrimp!
Posted by: PZ Myers
|
June 7, 2010 2:15 PM
Cephalopods don't have color vision. One species of firefly squid has been identified that has a bit of color sensitivity, but that's it.
Octopus have been trained in learning tests with colored blocks. If you hold luminance constant, they can't tell the difference between a red block and a blue block and a green block. They can very easily trained to recognize fine shadings of gray, however.
They don't do color matching when generating camouflage patterns -- it's simpler than you think, generating disruptive patterns.
Posted by: Gregory Greenwood
|
June 7, 2010 2:20 PM
I want to second Brownian @ 19. Sarfati's claim that;
"...it's because the eye needs a blood supply."
Makes no sense in the context of his supposedly omnipotent Sky Fairy. If god is all powerful, why does the eye 'need' a blood supply? Surely the eye should just work anyway god wants, unless Sarfati is suggesting that god is not all-powerful, and is actually subject to physical laws and the limitations of biology...
So, if Sarfati is saying that god-as-designer is subject to the rules of physical reality, would that make him a heretic in the eyes of the church?
Posted by: Phodopus
|
June 7, 2010 2:23 PM
PZ, some of the videos seem to indicate that the color shades of background rock are very closely matched by the cuttlefish. Is the perfect color match then a result of natural selection and their limited vision only gives cues what kind of rock the cuttlefish sits on without actually giving it the exact color?
Posted by: Balstrome
|
June 7, 2010 2:57 PM
You know, in an Honest debate, Sarfati would take what PZ has said about his argument and show where PZ is wrong, or admit that he, Sarfati is incorrect and adjust his opinion.
Then the discussion could move on and more knowledge about the world be generated. What is so wrong about doing things this way. Anyone want to disagree that if Sarfati managed to show that PZ was wrong in his statements, PZ would admit to it and change accordingly. (Yes, I know, Overlords don't, normally) But you get what I am on about.
Posted by: blf
|
June 7, 2010 2:58 PM
Phodopus@38, the speculation Pee Zed gave in his link @36 is:
Posted by: John Harshman
|
June 7, 2010 2:59 PM
1. There are two obvious ways to have color vision. Having receptors with different peak frequency sensitivities is one. But another way is to have a single type of receptor with a broad peak, and put different filters in front of them. Both methods are used in various species (and in combination too).
2. Don't be too sure that cephalopods can't see color. How many species have been tested? In such a diverse group, one might expect considerable disparity.
Posted by: Lynna, OM
|
June 7, 2010 3:04 PM
This was an absolutely delightful takedown of Sarfati, PZ. Thanks for the clear presentation, one that a non-biologist can comprehend.
I will look around to find some illustrations to complement the info -- this post is a keeper.
Posted by: Phodopus
|
June 7, 2010 3:05 PM
blf,
From some of the videos and pictures in that same post it seems that they seem to actually know exactly which shade of brown to use in each situation, far from some arbitrary natural shade.
Posted by: Nerd of Redhead, OM
|
June 7, 2010 3:14 PM
Ah nice take-down of a creobot PZ, and a lot information on eyes thrown in by the commenters. Makes for a very interesting and informative thread.
Posted by: And-U-Say
|
June 7, 2010 3:14 PM
A la #39, I wonder if Sarfati would ever read such a response? Responding to critiques of their articles is ever so rare, doesn't that suggest something right there? That the creationist case is total crap? You would think, but then, they don't.
Besides, any careful look at life in general and humans in particular make it clear that life is a complete kluge. Oh, sure... the casual look at Carmen Electra may seem to suggest otherwise, but in the details, its amazing we are even alive.
Posted by: ritchie.annand
|
June 7, 2010 3:21 PM
I've been doing a slow fisking of his Refuting Evolution book.
Unless he has some massive case of cognitive dissonance or multiple personality disorder, there is no way he's being honest.
It's like the smartass jerk from debate club who enjoyed arguing something false as true to fool half the people and frustrate the other half... who never grew out of that because they love being the Big Fish in the Ignorant Pond.
CMI has the entire book online.
(I'm working to the older print version, though perhaps I shouldn't be)
Posted by: blf
|
June 7, 2010 3:24 PM
Phodopus, were the background patterns identical except for the colouring? (I admit I haven't watched the video, mostly because I'm also preparing dinner right now!)
If not, then as explained in that post, they seem to be either matching or disrupting (counter-shading?) the pattern. If the patterns were identical, and they did colour-match, it would seem to be puzzle, especially if they can't actually see/detect the specific colour very well.
Posted by: Phodopus
|
June 7, 2010 3:27 PM
blf,
in particular the first two pictures in the middle in
http://scienceblogs.com/pharyngula/upload/2007/06/camo_patterns.jpg
Posted by: Pierce R. Butler
|
June 7, 2010 3:44 PM
... the cephalopod has merely stumbled across a solution ...
I'm trying to imagine a graceful and fluid cephalopod "stumbling" ... as metaphors go, this one is "... a peculiar pattern of kludgy patches ..."
Posted by: Rutee, Shrieking Harpy of Dooooom
|
June 7, 2010 3:44 PM
Shala, I think I love you.
Posted by: davem
|
June 7, 2010 3:50 PM
Never mind the eye, how does Sarfati explain the Giraffe's laryngeal nerve? That's not just bad design, it's criminal
Posted by: mikerattlesnake
|
June 7, 2010 3:57 PM
@48
You'd have to see it respond to two different colors of sand to judge whether it sees color. As it is, all sand in it's environment may be that basic color, likewise with the gravel.
They tested this with the grid in that same image, and the color is not matched.
Posted by: Aratina Cage
|
June 7, 2010 4:02 PM
PZ, such a scrumptious piece this was. It must go in your book to feed the masses!
---
QFT + ROFLPosted by: 'Tis Himself, Quel Dommage
|
June 7, 2010 4:06 PM
If the human eye is perfectly designed then why is my right eye 20/250 and my left eye 20/100? Shouldn't both eyes be 20/20 or better?
Posted by: https://www.google.com/accounts/o8/id?id=AItOawmVT1LBhwmO9ej9LNg7a5e9d-AVJ8ezfmE
|
June 7, 2010 4:26 PM
What is the advantage for cephalopods of being able to see the polarity plane of light? Does it make it easier for them to see camouflaged things in water?
Posted by: ckitching
|
June 7, 2010 5:14 PM
@Phodopus, I don't think colour matching is quite as essential as you assume. A cephalopod doesn't need to be able to blend into every possible background it could ever run across, and a bit of learning or instinct could let it prefer the types of backgrounds it blends into best. Most rocks of a given type in an area are likely to be fairly uniform in terms of colour, so the cephalopod only needs to know what types of hiding spots it's looking for.
Posted by: blf
|
June 7, 2010 5:14 PM
Phodopus@48, as mikerattlesnake@52 pointed out, some instances of apparent colour-matching doesn't really show much of anything, other than an ability to camouflage. I'd want to see the results with various identically-patterned but differently-coloured backgrounds (identically illuminated), and with the same background but differing illuminations (e.g., different colour filters, and perhaps different polarisations).
Posted by: MosesZD
|
June 7, 2010 5:18 PM
If God were an engineering major and I were a professor, I'd flunk him and recommend an easier major... Like religious apologetics, where bullshit counts as something, besides wrong.
Posted by: Kel, The Privileged View From Nowhere
|
June 7, 2010 5:36 PM
They always seem to miss the finer point: that the eye matches the pattern one would expect with common descent. Sure God could have designed it that way, but the fact remains that it's evidence for evolution.
Showing that the human eye doesn't fit into the pattern of common descent - that would perhaps be a more fruitful endeavour.
Posted by: Aaron Baker
|
June 7, 2010 5:55 PM
Very elegant and informative, Professor. Another non-biologist thanks you for your clarity here.
Posted by: evogene
|
June 7, 2010 6:01 PM
if Prof.Myers doesn't mind, I call this another creationist lie not misconception.
Posted by: jordin
|
June 7, 2010 6:12 PM
Best not to cite p.z. in any communications with the good doctor Sarfati, it upsets him. I do love the term atheopath though.
"Myers? He is a joke; such a dogmatic überleftist atheopath with the crude mentality of a hypersexualized government school teenager (see http://creation.com/global-atheists-reject-debate-challenge and http://creation.com/evolutionary-equivocation) that he can't see the obvious flaws in his and Dawkins' argument: since the retina is now called “an optimal structure” by experts in the field, precisely because of the "backward" wiring, it utterly fails as an argument from "bad design". Myers is just making an excuse that presupposes evolution to be true, and then explains away how this supposed bad design becomes “an optimal structure”.
Note that the critics like Dawkins, Miller and Myers have no qualifications in ophthalmology or spectroscopy, while I am an expert in the latter, and cite experts in the former (Drs Peter Gurney and George Marshall, e.g. http://creation.com/is-our-inverted-retina-really-bad-design).
Jonathan Sarfati, Ph.D."
Posted by: jemand
|
June 7, 2010 6:13 PM
We do have another really impressive kludge to increase visual acuity...
intelligence! Not only do we have the capacity to visually process images quite well just naturally, correcting some of the issues with the limitations of the actual eye with memory, interpolations, etc that give us a pretty good idea of what's going on, but we've even been able to EXPORT some of our vision.
To machines.
Which makes our visual acuity currently better than any other species, which doesn't have any such machines. We can also build corrective lenses and fix some other problems in an individual's sight as well.
But that's kind of neither here nor there in the current argument, I just think it's kind of neat.
Posted by: Nerd of Redhead, OM
|
June 7, 2010 6:21 PM
And a specialist in Raman Spectroscopy is an expert on UV/Vis eyes how?????Posted by: Kel, The Privileged View From Nowhere
|
June 7, 2010 6:23 PM
How are you for expertisse in evolutionary biology? That's the real question here, the human eye could be an example of fantastic design yet whether it's evidence for or against evolution depends on its relation to other evidence. Does the human eye have the same contingent marks as other vertebrate eyes? If so, then no matter how optimal the eye is, it is still evidence for evolution.If you want to argue against evolution, you need to argue against what evolution dictates. The best you have otherwise is that you could say the eye attests to the craftmenship of the eye-maker, but that says nothing over whether it evolved or not. You need to show that the eye does not fit the pattern of the tree of life.
by the way, how do you get around the problems of David Hume's criticism of the argument from design?
Posted by: https://me.yahoo.com/a/oCTtWpcLos1AluG7TfWegM5e0gCBvNv_LcRvaWc-#66f0b
|
June 7, 2010 6:27 PM
Not only polarized light, but CIRCULARLY polarized light. And as the Reverend pointed out, that thumbsmasher. My Marine Biology club is getting one of these babies. . . I can't wait =)
Posted by: SteveV, Death's Pissant Haberdasher
|
June 7, 2010 6:27 PM
Reminds me of the engineer's backhanded compliment
'a triumph of development over design'
(L.J.K. Setright on the Rolls Royce Merlin)
Posted by: Brownian, Most Vicious & Petty of Pharyngulites
|
June 7, 2010 6:36 PM
So, which is 'optimal'? The backwards wiring, or the forwards? Or is every single eye 'optimal'? If not, then what about the 'sub-optimal' ones? Did they evolve, or are they a product of a poor designer?
Finally, perhaps Dr. Safarti can gather all of his experts around and answer the question: In what fucking dictionary for creationist morons is an optimal structure less fucking effective than other structures with the same purpose (e.g. the avian eye, the mantis shrimp eye)?
Thanks, Jordan. I await your copy 'n' paste with bated breath.
Posted by: jp.tibirosen
|
June 7, 2010 6:44 PM
actually, the human eye is able, according to wiki, to perceive slightly the polarization of light: http://en.wikipedia.org/wiki/Haidinger's_brush
Posted by: Insightful Ape
|
June 7, 2010 6:44 PM
Oooh, Dr Sarafati, so your "experts" are now considering a blind spot a "perfect design"? How about the end-arteries supplying the retina, causing retinal infarction and field cuts? Those are "perfect" too? And when you have diabetes causing grow of new vessels, leading to bleeds inside the globe? You never think the avian eye without those vessels may be a wee better, or heaven forbid, the cephalopod eye? Hmmm...an eye with a blind spot and an eye without one...one may be better, but don't ask me which, I am no "expert". Funny though, the "experts'" opinion never finds it's way to peer reviewed jounals, only to anti-science propaganda websites.
Of course, this is not even the issue. The issue is, why don't you ever find a vertebrate eye with a blind spot, or a cephalopod eye with it. We are talking "preserved patterns" regardless of good or bad.
Why won't you creationists do your homework? The visual systems of many,many organisms haven't been studied yet. Find me one vertebrate (among tens of thousands of species) that doesn't have a blind spot. That will be enough to blow the biggest hole in evolutionary theory in 150 years. Are your "experts" too lazy to do the work, or what?
Posted by: mothra
|
June 7, 2010 6:46 PM
Legally blind lifelong, I had always expected to be totally blind by age 50 (so much for perfect design). However, thanks to advances in medical SCIENCE and associated surgeries, while I am still legally blind, I have the best vision of my life and long distance bicycling is now one of my hobbies.
Posted by: Brownian, Most Vicious & Petty of Pharyngulites
|
June 7, 2010 6:47 PM
Whoops, misspelled Dr. Sarfati's name. I hope he doesn't hold it against me, Bronwian, or Dr. PZ Meyers.
Posted by: PZ Myers
|
June 7, 2010 6:48 PM
Sarfati loves to play the authority game: he frequently cites some topic in which he claims to have a degree and in which his critics do not, as if we are so narrowly educated that we can't possibly know anything outside a very narrow domain (a restriction he does not apply to himself).
Sarfati has a degree in chemistry and a Ph.D. in spectroscopy, specifically applications of spectroscopy in chemistry. He knows nothing about biology or evolution, as his writings show.
My degrees are in biology, and my Ph.D. is from a neurosciences institute, for a thesis on neuronal development. The techniques I primarily use are various methods in microscopy, so I do know a fair bit about optics. I'm afraid my credentials on this particular topic trump his, so he really shouldn't be wasting his time with that line of argument.
Posted by: co
|
June 7, 2010 6:54 PM
Oh boy. I can't wait to go toe-to-toe on optics and spectroscopy. Bring it on, Jon.
Posted by: chase.j.johnson
|
June 7, 2010 7:08 PM
As an electrical engineer, I did find it interesting that Dawkins claimed no designer would design a backwards photosensor system, because most modern CMOS photosensors are in fact backwards. The wiring is on top, because that's the traditional, simple way to fabricate CMOS chips. Newer back-illuminated models do it the better way, with photosites on top and wiring underneath. Of course, the reason sensors were designed backwards was that it was cheaper and more reliable to produce them the traditional way, and obviously, they work just fine. Now that light sensitivity is turning into the next megapixel race, and fab techniques are much more advanced, though, you can buy some extra sensitivity by fixing the sensor layout.
Every time I see this example, though, it jars me for a moment, because it's just not true that human designers wouldn't design photodetection systems that way.
Posted by: Mu
|
June 7, 2010 7:22 PM
Tis'himself @54, the reason for your poor eyesight is naturally NOT God's design but your sinful lifestyle. Your only chance it to go and repent, or, in case your faith doesn't give you that option, lasic. The later worked for me, and was a good bit cheaper than tithing.
Posted by: Qwerty
|
June 7, 2010 7:33 PM
I always find it amusing that creationists (the majority of whom are not biologists) constantly want to lecture biologists.
It's kind of like a plumber passing himself off as a heart surgeon because he understands tubing
and water heaters.
Posted by: amphiox
|
June 7, 2010 7:56 PM
Well, Dawkins is not an engineer, so it's simply an example where he's speaking outside his area of expertise, and is mistaken.
But, as your post so eloquently describes, the reason human designers do design photodetection systems that way is because they are imperfect, limited designers! Their techniques are not all-powerful, and they are forced to make compromises for the sake of convenience. An omnipotent designer would have no such limitations, and the only reason to include this kind of compromise would be on a whim - in which case he's an ass.
Posted by: Insightful Ape
|
June 7, 2010 8:41 PM
Dawkins is fallible.
Hallelujah!
Now am I going to get burned at the stake for my heresey by those "fundamentalist atheists"?
But I will take the liberty to modify his statement:
no human designer would build an ass-backwards array of receptors like the human retina, GIVEN THE ALTERNATIVE. And the alternarive does exist in the animal world (squid eye).
Posted by: T. Bruce McNeely
|
June 7, 2010 8:43 PM
Perhaps Dr. Sarfati should consider the following:
I see that a number of my fellow myopes have already commented. We are legion. Why?
Pretty much everyone has presbyopia by the time they hit their mid-forties. Why?
Cataract surgery is now one of the most frequent operations. Why?
Posted by: amphiox
|
June 7, 2010 9:08 PM
When it comes to cephalopod eyes, I think one of the best examples of imperfect design is actually the nautilus.
The poor nautilus has a pinhole camera eye. The thing with pinholes is that the smaller the hole, the sharper the image. But the smaller the hole, the dimmer the image.
So how can you fix that problem? By adding a lense to focus the light. With a lense you get an image that's both sharp and bright.
And where is a lens most useful? When the ambient light levels are low. Like the deep ocean.
And where does the poor nautilus live?
It's own close relatives have lenses, but it does not.
Pity the poor nautilus, Cthulu's least favorite son. . . .
Posted by: KingUber
|
June 7, 2010 9:26 PM
Jonathan Sarfati is a good chess player
Posted by: Kel, The Privileged View From Nowhere
|
June 7, 2010 9:34 PM
Voltaire had this question sorted out some 250 years ago, said by Dr Pangloss in Candide: "Observe that noses were made to wear spectacles; and so we have spectacles."Yes this truly is the best of all possible worlds!
Posted by: chase.j.johnson
|
June 7, 2010 10:14 PM
Certainly the case, and we already have superior designs coming to market. It only took us a couple of decades; God's obviously a slow learner.
Posted by: Kel, The Privileged View From Nowhere
|
June 7, 2010 10:28 PM
The sad thing about this line of argument is that David Hume utterly destroyed it over 250 years ago. As finite and contingent beings, we have the complete lack of ability to detect the infinite as all we know is finite and contingent. Design cannot be an argument for God, however optimal and clever we may think of a design we can't say that it's perfect. We just don't have the capacity for it.
That something has obvious flaws makes it pretty easy to make the case against an intelligent designer, but still the entire argument at best is going to make the designer alien life that evolved on another world.
Posted by: jahigginbotham
|
June 7, 2010 11:33 PM
As #75 chase johnson points out (it took me a while to register), many ccd detectors are built backwards.
http://www.specinst.com/Graphics/back-front-illuminated.jpg
The 'wires' connecting the photocells to the brain run over all the surface of the retina, so the light rays have to pass through a carpet of massed wires before they hit the photocells. That doesn't make sense…
What Dawkins wrote is quite correct
nope
Posted by: petrander
|
June 8, 2010 1:36 AM
Well, whaddayaknow!
Evolution is like "code-and-fix". A true hacker!
Sounds like evolution could need a few lessons in proper systems development and the application of some "design patterns".
Posted by: Rutee, Shrieking Harpy of Dooooom
|
June 8, 2010 3:19 AM
If the eye is so optimal, why are my glasses functional, rather then cosmetic?
Posted by: Caine, ghetto féministe
|
June 8, 2010 3:37 AM
Rutee:
I have the same question. To add a bit, if the eye is so wonderfully designed, why did I require glasses at the age of eight?
Posted by: Kel, The Privileged View From Nowhere
|
June 8, 2010 4:06 AM
I answered this already in #83:If you find that answer unsatisfying, then you can't argue with that your necessity for God's punishment is because you masturbate. Your glasses are your own fault!Posted by: herr doktor bimler
|
June 8, 2010 5:54 AM
Octopus have been trained in learning tests with colored blocks.
These people reckon that at least one species (Octopus aegina) makes colour discriminations even when lightness is controlled. The article's in Japanese, though, so I've only read the abstract.
Posted by: herr doktor bimler
|
June 8, 2010 5:58 AM
Link fail, trying again:
http://rms1.agsearch.agropedia.affrc.go.jp/contents/JASI/pdf/society/62-1620.pdf
Posted by: AJS
|
June 8, 2010 10:17 AM
So basically his argument boils down to "It must be better to have the retina backwards, because that's the way it is in humans" ?
Sounds like begging the question to me.
Want more fun, ask why an intelligent designer (especially one supposed to be male) would put balls on the outside. And follow it up by asking why an intelligent designer with free rein over such matters would design sperm not to work at the body's internal temperature. Or why the delivery system would be so inefficient that so many hundreds of millions of them would be doomed to go to waste even in a successful conception.
The body is not a work of art, but an entry on Scrapheap Challenge.
Posted by: wwsprague
|
June 8, 2010 2:22 PM
@28, Actually the reason you use rods at night is because they are significantly more sensitive (some evidence suggests they are single photon detectors) to incoming light. It also just so happens that there is only one type of rod, so you are correct in that there is no way to discern color with them and that they overlap a great deal with the cone wavelengths. This is also why you can't look directly at something at night and see it well. That specialization of the fovea that PZ mentioned also compromises on night vision, since there are no rods there.
Posted by: wwsprague
|
June 8, 2010 2:26 PM
Also, for anyone interested, a fantastic resource of pretty much everthing human vision related is the University of Utah's Webvision site. http://webvision.med.utah.edu/
Posted by: Ian Derthal
|
August 20, 2011 4:53 PM
You should have gone along to the conference PZ !