Insight Into Eye Evolution Deals Blow To Intelligent Design

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A recent article has filled another gap in our ignorance (and created two new gaps) about eye evolution. As reported in

Insight Into Eye Evolution Deals Blow To Intelligent Design

How complex and physiologically remarkable structures such as the human eye could evolve has long been a question that has puzzled biologists. But in research reported this week in Current Biology, the evolutionary history of a critical eye protein has revealed a previously unrecognized link between certain components of sophisticated vertebrate eyes - like those found in humans - and those of the primitive light-sensing systems of invertebrates. The findings, from researchers at the University of Oxford, the University of London and Radboud University in The Netherlands, put in place a conceptual framework for understanding how the vertebrate eye, as we know it, has emerged over evolutionary time.

See also How the vertebrate eye, as we know it, emerged over evolutionary time?

Ref: Current Biology, Vol. 15, pages 1684-1689, September 20, 2005. DOI 10.1016/j.cub.2005.08.046

Urochordate βγ-Crystallin and the Evolutionary Origin of the Vertebrate Eye Lens Sebastian M. Shimeld, Andrew G. Purkiss, Ron P.H. Dirks, Orval A. Bateman, Christine Slingsby, and Nicolette H. Lubsen

Abstract:A refracting lens is a key component of our image-forming camera eye; however, its evolutionary origin is unknown because precursor structures appear absent in nonvertebrates [1]. The vertebrate βγ-crystallin genes encode abundant structural proteins critical for the function of the lens [2]. We show that the urochordate Ciona intestinalis, which split from the vertebrate lineage before the evolution of the lens, has a single gene coding for a single domain monomeric βγ-crystallin. The crystal structure of Ciona βγ-crystallin is very similar to that of a vertebrate βγ-crystallin domain, except for paired, occupied calcium binding sites. The Ciona βγ-crystallin is only expressed in the palps and in the otolith, the pigmented sister cell of the light-sensing ocellus. The Ciona βγ-crystallin promoter region targeted expression to the visual system, including lens, in transgenic Xenopus tadpoles. We conclude that the vertebrate βγ-crystallins evolved from a single domain protein already expressed in the neuroectoderm of the prevertebrate ancestor. The conservation of the regulatory hierarchy controlling βγ-crystallin expression between organisms with and without a lens shows that the evolutionary origin of the lens was based on co-option of pre-existing regulatory circuits controlling the expression of a key structural gene in a primitive light-sensing system.

See also Bookmarks matching tag eye at Connotea

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Alright, now they've gone too far. I thought I'd seen every specious and fallacious argument and example that creationists could throw out there, but I was wrong. They're muscling in on my turf! now! No, they're not making fallacious arguments... Read More

34 Comments

Yes! Chalk one up for the good guys!

An Ernst Mayr quote that should be more widely known:

Ernst Mayr Wrote:

Photosensitive, eyelike organs have developed in the animal series independently at least 40 times, and all the steps from a light-sensitive to the elaborate eyes of vertebrates, cephalopods, and insects are still found in the living species of various taxa (Fig. 10.2). They include intermediate stages and refute the claim that the gradual evolution of a complex eye is unthinkable (Salvini and Mayr 1977). [Mayr, What Evolution Is]

And who can forget “Dr. Richard Paley’s” article on the impossibility of eye evolution (sending up the creationist canard “what use is half an eye?”), featuring this image of the “first eye.”

Photosensitive, eyelike organs have developed in the animal series independently at least 40 times

But they all use the same HOX genes.

I’m curious - is “Dr. Paley” over at objective ministries actually a parody? The stuff on that site is so wacky it is hard to believe it is real, but if it is a parody they are playing it fairly straight (not like the equally funny Intelligent Design Society of Kansas).

I mean, the objective ministries folks actually have the following statement on one of their pages:

The Internet was created by the United States of America - a Christian nation [ref. 1, 2, 3] - and should not be used to spread anti-Christian, secular, or non-Christian propaganda and hatespeech. This is our Internet, and we should exercise our position as its owners and as the guardians of civilization to stop its misuse.

And their evolution stuff is just nuts. Sadly, not outside of the craziness level of some creationists (oops, ID advocates). But really… extant pterosaurs and Moses with a pterosaur-scarin’ staff …how nuts do you have to be to buy into that for real. That has got to be a parody (crossing fingers and hoping!).

Regardless of whether the site is a joke, it did have a fun “convert an atheist beatnik” game at the bottom, and a link to report pornography on the internet (better hurry, I’m not sure if the gov’t knows about folks usin’ the net for porno, and I’d hate for there to be to many dirty pictures on the net…).

“Dr Paley’s” parody of creationism was so marvellous (right down to the reference to halfwit pretend doctors like Hovind) I played along with his joke by emailing him:

your article on the eye was excellent, but darwinists do even worse than you have pointed out. if evolution is true, then at some point there must have been a half a person jumping around on one leg and oozing brains and blood from one side of his body. I think we need to keep the argument as simple as possible if we are going to fight the stupidity of darwinism.

Did anyone else look at the game theory reference complete with pascal’s wager on the objective ministries site (Christian Game Theory ). I am now completely convinced that being a heathen evolutionist will result in my demise

“A payoff matrix for the Pascal’s Wager game makes it clear to the Atheist that his infinitely best choice is to accept the existence of God.”

One problem with the Pascal wager: Which God or Gods do we accept and what is/are these gods jealous gods? In other words, what if by accepting the wrong god we are doomed? The problem is that the wager is presented as an either or.

PvM wrote: “One problem with the Pascal wager: Which God or Gods do we accept and what is/are these gods jealous gods?”

Not only that – what does it mean to accept God? It seems to mean you listen and obey which ever human being or old and incomprehensible book claims to speak for God. God doesn’t seem to speak on his own behalf.

The threat and promise always comes from a human being.

One problem with the Pascal wager: Which God or Gods do we accept

Indeed, what happens if we die and find ourselves standing before Zeus or Odin?

Seems that the only way to be sure of winning is to worship ALL gods and goddesses . . but wait, some of them get really really pissed if you worship any other god or goddess.

A quandary, isn’t it . … .

Yet again we see why the “god of the gaps” argument just won’t do. The longer researchers plug away, the more gaps are filled—and the smaller the space in which ID advocates can hide.

So the vertebrate eye, as we know it, has emerged through co-option. Oh, that explains it. The eye evolved through evolution.

Joel Wrote:

So the vertebrate eye, as we know it, has emerged through co-option. Oh, that explains it. The eye evolved through evolution.

Very good.

Objective Ministries is indeed a parody, Edward.

In connection with Pascal’s Wager there are basically two problems. As others have pointed out, “which god?” It can be applied to any religious belief, making it useless. In a related manner, it is a gutless wager (perhaps that is its appeal to some so-called Christians); it requires no actual faith, no commitement involving one’s soul. Someone espousing the benefits of Pascal’s Wager either has the shallowest commitment to their faith or flunked out of seminary.

Homer Simpson’s refutation of Pascal’s Wager:

“But Marge, what if we chose the wrong religion? Each week we just make God madder and madder.”

Another problem with pascal’s wager is that it assumes that if god exists (let’s just say it’s the christian one, since you probably won’t hear pascal’s wager from a Buddhist or pagan) He wants to be acknowledged. We have no proof of whats required to gain God’s favor. Perhaps God just wants us to enjoy the marvel of creation and leave him alone. Perhaps by praying to him and disturbing him you’re really just upsetting him and sending yourself to eternal hell, where as the atheist who just lived his life is then rewarded.

It can’t form a reward punishment table with just a guess at what the supreme being of all (who may not exist) wants and then call it evidence that any unbeliever is screwed. If you don’t know the rules of the game you can’t claim to understand the how to get the prize.

Comment #49478

Posted by Edward Braun on September 24, 2005 05:47 PM (e) (s)

I’m curious - is “Dr. Paley” over at objective ministries actually a parody? The stuff on that site is so wacky it is hard to believe it is real, but if it is a parody they are playing it fairly straight (not like the equally funny Intelligent Design Society of Kansas).

I have a suggestion Ed, for how to tell the parodies from the real creationist sites. I hate to say this, but you can keep a secret, can’t you Ed? You see, it’s secretly true that CSI and the Explanatory Filter actually work perfecty. We just don’t admit it, because the vast majority of us scientists are committed to a lie, but in fact brilliant revolutionaries like Dembski have transformed all of science with their penetrating insights. CSI and EF always reliably detect intelligence behind an object.

So what you do is, take the webpage in question, and apply those ID methods. If the EF says there’s an Intelligent Designer behind the webpage, you know it’s a parody. If the EF says there’s no intelligence behind it, you know it’s real creationism. ;-)

another problem with pascal’s payoff matrix:

if you only accept god’s existence in order to assure entry into heaven, you are committing ‘false witness’, since you pretending belief only to fool the deity. and since the deity is omniscient, (he)’ll see right through it and it’s brimstone time!

My preferred comeback to “what use is half an eye?”, is: “Depends which half! The back half is good enough for a worm.…”

The three main problems with Pascal’s Wager:

1. As mentioned above, which god?

2. What deity worth his/her/its salt would accept what amounts to an insurance policy as a form of genuine belief?

3. The subjugation of one’s intellectual integrity. Believing in a god “just in case” is the same as believing in something “you know ain’t so,” to paraphrase Twain.

Abstract:A refracting lens is a key component of our image-forming camera eye; however, its evolutionary origin is unknown because precursor structures appear absent in nonvertebrates [1]. The vertebrate βγ-crystallin genes encode abundant structural proteins critical for the function of the lens [2]. We show that the urochordate Ciona intestinalis, which split from the vertebrate lineage before the evolution of the lens, has a single gene coding for a single domain monomeric βγ-crystallin. The crystal structure of Ciona βγ-crystallin is very similar to that of a vertebrate βγ-crystallin domain, except for paired, occupied calcium binding sites. The Ciona βγ-crystallin is only expressed in the palps and in the otolith, the pigmented sister cell of the light-sensing ocellus. The Ciona βγ-crystallin promoter region targeted expression to the visual system, including lens, in transgenic Xenopus tadpoles. We conclude that the vertebrate βγ-crystallins evolved from a single domain protein already expressed in the neuroectoderm of the prevertebrate ancestor. The conservation of the regulatory hierarchy controlling βγ-crystallin expression between organisms with and without a lens shows that the evolutionary origin of the lens was based on co-option of pre-existing regulatory circuits controlling the expression of a key structural gene in a primitive light-sensing system.

Or in layman’s terms: ‘Similarity proves evolution.’ This is considered a blow?

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Did you even read the article?

This is why I applaud the efforts of IDers like Blast, ID Troll, and Creationist Troll (note that these last two might be one and the same, “Creationist Troll” perhaps being so embarrassed by his obvious pig-ignorance the last time he was here that he has now decided to troll under a new name).

As I noted before, the ID/creationists like to make a big production out of how wonderful and amazing and fantastic God’s Creation is, how wonderfully diverse and resplendent all life is. Yet, by posting such drivel as Blast’s “too small to be a whale” and CT’s “birds can’t live without crops”, they simply show everyone how utterly absolutely totally pig-ignorant they are about ANY of it. My nine year old niece learns more about biodiversity by watching one weekend of the Discovery Channel than the uneducated ID dolts here ever even learned in the first place.

Combined with the repeated demonstrated inability/unwillingness of the ID’s “best and brightest” to answer simple direct questions, the IDers here do a wonderful job of demonstrating to all the lurkers how utterly vapid and useless ID “science” really is, and how dishonest and flat-out ignorant IDers really are.

We should thank them for that.

ID Troll Wrote:

Or in layman’s terms: ‘Similarity proves evolution.’ This is considered a blow?

Based on that comment, I suspect you don’t care to understand this stuff - you just want to dismiss it. But in case I’m wrong (and if so, my apologies for the assumption), try looking at it this way.

Evolution says new functions, organs, etc., arise by modification of existing functions. Thus, evolution predicts that we’re likely to find genes like the one described in the paper - genes that are similar to the inferred ancestral gene of the vertebrate βγ-crystallin genes.

And voila - we found one (for the umpteenth time).

ID/Creationism predicts nothing about any of this. An omnipotent creator/designer could have created each new function from whole cloth, with no recycling of existing genes & components. Or, s/he could have done it exactly the way we observe, for his/her own inscrutable reasons.

The point is, evolutionary theory makes successful predictions about things we expect to find, but haven’t yet found. Creationism/ID does not. That’s why evolutionary theory is science, and Creationism/ID is not.

The other point is that evolution is not considered to be a scientific theory based on one key finding. No one’s claiming that a single instance of similarity proves evolution, as you derisively suggest. The claim is that evolution makes certain predictions about how vertebrate eyes may have arisen, which leads to further predictions about genes we can expect to find in distantly related organisms. And when such predictions come true time after time after time, we call it a scientific theory.

This particular finding doesn’t prove evolution. It’s just one more thing to add to the already enormous list of facts and successful predictions that support the validity of the theory of evolution.

All I can say is thank the Flying Spaghetti Monster that the objective ministries site is a parody, though it is sad that I was contemplating the possibility that it wasn’t. The scary part is they aren’t *that* much more extreme than “Dr.” Kent ([t]ell the editors [of Scientific American], or any other evolutionist for that matter, I’d be honored to debate them in front of any university with half of my brain tied behind my back) Hovind. However, had I checked out the “Zounds” rock ministry with their “rock star” - who looks like a negative of John Bolten - it would have been more obvious - a little too over the top there!

On the other hand, the Current Biol paper sounds like an excellent example of what actually thinking about the interesting issues that common ancestry brings to the fore can do for us. The coming availability of multiple invertebrate chordate genomes (Broad has completed another Ciona species and JGI has sequenced the lancelet) will doubtless catalyze the discovery of more interesting changes that led to “vertebrate” features. Funny how actually DOING science can lead to interesting discoveries, while sitting back and calling things “irreducibly complex” doesn’t lead to much other than poorly concieved simulations a la Behe.

ID Troll -

At least you’ve named yourself accurately.

“Or in layman’s terms: ‘Similarity proves evolution.’”

The theory of evolution is a scientific theory which generates testable predictions. “Intelligent Design” does not, but ID advocates would argue that it is an “alternative” to the theory of evolution. ID would actually be worthless even if the theory of evolution didn’t exist, but we can say, in some sense, that when the evidence fits what the theory of evolution would predict, it is a blow to ID.

Sebastian et al could have discovered, in their scientific investigation, evidence which did not clearly match what the theory of evolution would predict, but the opposite happened.

“This is considered a blow?”

Obviously it is.

Your implicit argument is “If all eyes were dissimilar at the molecular level, that would be a challenge for evolution and in that sense ‘support’ intelligent design. But if eye expression relies on common molecular genetic components across species, this doesn’t argue against ID.”

In other words, the concept of “ID” is completely worthless from a scientific point of view (no matter what the religion of the scientist) because it can’t possibly be tested. ID advocates merely declare that everything always supports ID, no matter what. If you disagree, prove me wrong, by answering this question -

What would you accept as evidence AGAINST ID?

Also - and please be specific -

What is the theory of ID? Can you explain, in detail, how ID created the many eyes we see in the natural world? Who is the designer? How did the designer act, in specific terms, at the molecular level? What experiments can we use to test your assertions?

There’ve been some good problems with Pascal’s wager pointed out already. My problem with the wager is with the values of “infinity” and “one” being mis-applied:

In the first of our two payoffs, a person’s “life” of some sort can endure for an infinite amount of time. This “one” life, if it exists, would indeed be very valuable, perhaps infinitely valuable.

But, if god really doesn’t exist, and all we’ve got is this tiny blip of a lifetime in the infinite vastness of the universe, then our “one” life here is infinitely more precious to us than one that could last an eternity.

As usual for Deep Questions, Terry Pratchett offers a parable featuring a parallel Pascal in the Discworld afterlife:

”…the Quirmian philosopher Ventre, who said, ‘Possibly the gods exist, and possibly they do not. So why not believe in them in any case? If it’s all true you’ll go to a lovely place when you die, and if it isn’t then you’ve lost nothing, right?’ When he died he woke up in a circle of gods holding nasty-looking sticks and one of them said, ‘We’re going to show you what we think of Mr. Clever Dick in these parts…’” - Hogfather, pg 52

You guys realize that the “Christian Game Theory” article was a joke, right?

The satire at “Objective Ministries” is rather gentle and extremely intellectual (I would assume that no-one with a sense of humor would be offended by it, whatever their religion), but it’s still obviously satire.

Think about it - the name of the “theobiologist” is “Dr Paley”…Paley…watchmaker…get it?

ID Troll Or in layman’s terms: ‘Similarity proves evolution.’ This is considered a blow? Good the clowns are back in action. But where’s the chief flunkey of the dear leader Salzo Corza? Looks like the fig newton and limbo king is lying low waiting for one of his trolls to make sense of the paper and present the idiot’s guide so that he can churn out one more picture book. At the rate he is going Jack Chick will soon face stiff competition.

The scary part is they aren’t *that* much more extreme than “Dr.” Kent

OMG, guys, you didn’t realise Kent Hovind is a parody? cringeworthy…

Pascal’s Wager is only one argument for the existence of God; obviously not one of the strongest, but valid nonetheless. There are many other arguments that can be used to prove the existence of a “Designer”. Look into it, maybe, before you refute everything. Theology is a remarkably valuable tool in learning the proofs of God; get any dictionary to tell you the meaning of the word “faith”, and then do your own research.

Ahem…Pascal’s Wager is not an argument for the existence of god. It is simply an argument from pragmatism. In other words, it is an argument for the BELIEF in the existence of god, clearly illustrated by its basis in utility. But the wager is weak, as is amply demonstrated here.

I really don’t think theology is in the business of “proving” anything, and except for mathematics, neither is science. Furthermore, if you think faith magically proves your god, then I don’t think we’re using the same dictionary.

Actually, what _does_ ID say about the eye? Did it evolve or was it designed? And what if the design process was subtle enough to be indistinguishable from evolution?

R

About this Entry

This page contains a single entry by PvM published on September 24, 2005 2:20 PM.

Of Pandas and People: Creation Relabeled was the previous entry in this blog.

Kansas BOE Chair - It’s either the evolution or the Bible, not both is the next entry in this blog.

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