Evolution of the eye? The myth goes on...

In simple cells (such as Euglena), "sight" can be compared to chemotaxis. It senses something (light or nutrient gradient) and moves toward this stimulus. Euglena use pterin and flavoproteins (look here) in order to chemically sense light. If a single cell can do it can't be that complicated. In fact, flavins and cartenoids have also been suspected in light gradient preference in sponge larvae (look here). What would you consider "simple sight" so that we could start on firm ground as to the definitions of simple and complex. I can see your argument. The old adage of you can't see the forest for the trees. But here we are trying to find the makeup of the tree so that we can explain the forest. We are not blind (bad pun) to the complexity of the whole problem, but we don't throw our hands up in the air and decide that we can never understand it. Maybe the question should be, can we understand the forest by ignoring the trees?Oh, and by the way, reductionist methods are able to explain photoreceptors by breaking down each step. I was just reading through a molecular biology text and this is what it had to say about rods:Molecular Biology of the Cell, 3rd ed., Garland Publishing, 1994.
Transcribed, all spelling errors are the fault of the tyist (me)."Rhodopsin, as we noted earlier, is a seven-pass transmembrane molecule homologous to other members of the G-protein-linked receptor family, and, like its cousins, it acts through trimeric G protein. The activating extracellular signal, however, is not a molecule but a photon of light. Each rhodopsin molecule contains a covalently attached chromophore, 11-cis retinal, which isomerizes almost instantaneously to all-trans retinal when it absorbs a single photon. The isomerization alters the shape of the retinal, forcing a slower conformatinal change in the protien (opsin). The activated protein then binds to the trimeric G-protein transducin, causing the alpha subunit to dissociate and activate cyclic GMP phosphodiesterase, which hydrolyzes cyclic GMP, so that cyclic GMP levels in the cytosol drop. As a consequence, cyclic GMP dissociates from the plasma membrane Na+ channels, allowing them to close. In this way the signal passes from the disc membrane to the plasma membrane, and a light signal is converted into a electrical one."As you can see, complicated but not really that different from any other cell function I could list. In fact, rhodopsin is related to other trans-membrane proteins that react to molecules instead of light. By breaking it down, sight can be considered a photochemical reaction that potentiates an electrical signal that can be sent to the brain for processing. Perhaps you could give us another methodology, besides naturalistic ones, that could have led us to a better understanding of light sensing?The sight you talk about with the horseshoe crab goes beyond simple light sensing, but rather light focusing and reaction to stimulus. As said by other people, light sensitive chemicals are the root of sight (in our case 11-cis retinal and others). Without chromophores the rest of the structure would be meaningless. This is why acquiring light sensitive reactions is thought to be the first step in eye development and a simple version can be seen in Euglena.Perhaps you could explain what you think the impossible steps are in eye evolution. This might lead to better discussion instead of arguing over which chemicals are photosensitive.

Well, no, I don't understand why you didn't respond, since it was so quick and easy to do so, and in doing so you have helped me clarify your views. Thank you.On question 1, I see there's no problem until the final step. But I think you've misunderstood me. (See, these questions are useful!)All I'm saying is that one of the chemical compounds in the reaction is a protein produced from the genetic code. We all agree that proteins are produced based on DNA sequences, right?So, are we in full agreement on my question that all these individual steps are all quite likely? It was indeed my point that all these individual pieces were obviously true; however, previous discussion with you left me thinking you had some problem with it. Clearly we must not have been communicating clearly with each other. If you now agree with my statement from question 1, I'll move on.My follow-up question, also a small one: Given that you do accept the above to be likely, do you also agree it is quite possible for the chemical reactions in question to have a biological effect? I also think this is obviously true...do you?Regarding question 2, you write:

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Look here, if you isolate a single chemical reaction then you will find a number of natural mechanisms capable of explaining/generating that reaction - I certainly won't argue that point.

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Good. I hope not!

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The problem is that even a "simple" vision system (say, that of a horseshoe crab) ISN'T a single chemical reaction.

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I have a lot to say about this. I'll try to limit myself to keep the discussion focused.1. Why do you call a horseshoe crab's vision system "simple"? It strikes me as a particularly complicated visual system, that I agree could never spontaneously arise fully formed. Can you come up with no simpler example of a vision system?Finally, an additional question:When we are talking about "vision", we merely mean an animal detecting photons in a way that can meaningfully influence the animals state or behavior, right? I assume that things like color perception, movable eyes, and art appreciation are things that are unnecessary to be present for a vision system to exist.This is important, I think, though very basic. If we're talking about "vision", let's make sure we're talking about the same thing. The title of this thread is "Evolution of the Eye", and if we were indeed talking about the eye, it would be pretty clear, I think, what we were talking about. "Vision" is more abstract, so let's make sure we're on the same page.

Ahh, it appears that my good friend Jorge (aka. Joralex) from the theologyforums is continuing to use the same old lame arguments which have been debunked on other boards. He is also using the same insults.Go to this site to see for yourself:
www.theologyforums.com

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But, of course, you will insist that it does work since this is part of your belief system - materialistic Naturalism.

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And Jorge, erm, Joralex keeps singing the same, rusty old tune. edited url to fix page width - The Queen[This message has been edited by AdminAsgara, 11-09-2003]

I think Joralex's arguments aren't lame. In fact, I know so. I fully agree with the statement that eyes of humans, insects or anything else that has the ability to see, cannot possibly have evolved.
I agree that some organisms receive light and react on it, like plants turn to light. (Notice the word "receive".) But, these organisms like plants and some bacteria don't really see the light, because they are not aware of it. In order to comprehend a light signal from outside, you need a brain part that receives the signal through a medium, like a nerve that goes from detector to processor.
If there is this light sensitive spot you guys keep talking about, no organism will have any advantage by just having that spot. It needs a medium and processor part in order to interact.
Let's imagine an organism mutating over time. Even if a mutation would accur (very little chance) that would provide the organism a so-called 'light sensitive spot' then how can that signal have any effect, because there's no way it can be transported to a brain or something like that. You're not gonna tell me that you evo's believe that by random mutations an organism may gain a sensor, channel and processing-unit without losing one of the three in the meantime?The whole idea of eye-evolution is ridiculous, it's like letting a monkey build a computer with rubbish. The chances are completely nada that this will happen in real. Even if you already have a simple eye, it could never evolve to become better.Infinity

I'm just curious as to whether you have something beyond "argument from personal incredulity" to offer in this thread?

Wrong. The probability of a mutation is a not only very good...it's a certainty. Mutations occur all the time. You have thoudsands in your DNA right now. True...if we follow the twisted logic of a ID creationist. On the other hand, if you follow the scientific method and if you would attempt learn something about the ToE...this becomes a non-issue. No, we're not. Actually, your statement is what's ridiculous. What does a monkey trying to build a computer out of rubbish have to do with evolution? Is there some new aspect of the ToE that deals with computer building monkeys? Are they the same ones that were also going to bang away on typewriter and reproduce the works of Shakespeare?

No.I agree that an eye without a brain is useless, and therefore not selected for.However are you going to tell me that a brain without eyes is useless? Hardly. The brain has other functions besides the recognition of visual data.An organism could easily evolve the "channel" and "processor" because these structures have utility beyond responding to visual data. After all blind people don't stop thinking, do they? With these strutures already in place it's little challenge for a photo-sensitive cell to evolve - probably by co-option of a sensitive cell already "hooked up" to the primitive nervous system. Why? Just because you say it doesn't? I don't believe you. Personally I find the continuous gradient of complexity in eyes in the animal kingdom quite convincing.

Infinity writes:
...Even if a mutation would accur (very little chance)...Fliesonly:
"Wrong. The probability of a mutation is a not only very good...it's a certainty. Mutations occur all the time. You have thoudsands in your DNA right now."Would you please NOT quote only PART of my sentence? If you'd read the whole piece before writing this, you would have understand that what I meant was that the chances of all the POSITIVE mutations that lead to a light-sensitive spot are nihil. The chance that a so-called light-sensitive spot suddenly is made due to some RANDOM changes in the DNA is (almost) 0.Fliesonly: "What does a monkey trying to build a computer out of rubbish have to do with evolution?"At least you got me convinced you still have a monkey-like brain in you, but let's clear this one up for you. My example was only to demonstrate the improbability of positive mutations. Evolution has no goal, that is what all evo's say. It's power lies in random mutations. Well, here's the buzz: the chance alone that random mutations in the DNA of some organism will create a light-sensitive spot is already as IMPROBABLE as a monkey that builds a computer out of rubbish, whithout ever having seen one. Understand it now? And I never mentioned anything about a computer building monkeys.OK I believe Crashfrog said something about the processor not being useless without the eye, that's true of course if you use the word 'processor' instead of 'brain'. I'm sorry CrashFrog but you didn't catch me at this one. What I meant (which should be obvious) was that without a special part of the brain (like a vision-processor) that translates the signals coming from the 'eye', the eye would be useless. I don't state the brain is useless without the eye, but if there would have been a part of the brain that is able to translate the signals coming from the eye, while there is no eye, that brain-part or vision-processor is useless. See my point?
Like Joralex said: you got the sensor, medium (important as a wire for electricity) and a processor-part in order for SIGHT to work. All three of them, you can't even let the medium out because the connection from 'brain' to 'eye' is already a medium, even if the two are right next to each other (also VERY little chance for that)..Of course you may keep thinking that gradual increasing organs lead to things like sight, but even I don't believe in Santa Clause any more... After reading some interesting books on the subject and discussing it with other people like you, I'm convinced that evolution doesn't work. It's not a proven fact, as some people like to state. It's really just a NON-scientific THEORY. "Micro-evolution" does occur, that's right. We see various types of cats: all mutations of some sort of pre-cat. Same with dogs and a lot of other animals. But do you notice any change in upward direction (increased complexity)?Infinity

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Would you please NOT quote only PART of my sentence? If you'd read the whole piece before writing this, you would have understand that what I meant was that the chances of all the POSITIVE mutations that lead to a light-sensitive spot are nihil. The chance that a so-called light-sensitive spot suddenly is made due to some RANDOM changes in the DNA is (almost) 0.

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There are certainly many people who have bothered to educate themselves on this subject in far greater detail than youInt J Dev Biol. 2002 Jan;46(1):65-73. Related Articles, LinksThe genetic control of eye development and its implications for the evolution of the various eye-types.Gehring WJ.Biozentrum, University of Basel, Switzerland. Walter.Gehring@unibas.chMutations in the Pax 6 homologs of mammals and insects prevent eye development and targeted expression of both mammal and insect Pax 6 homologs is capable of inducing functional ectopic eyes. Supported by RNA interference experiments in planarians and nemerteans, these findings indicate that Pax 6 is a universal master control gene for eye morphogenesis. Since all metazoan eyes use rhodopsin as a photoreceptor molecule and the same master control gene for eye development, we postulate a monophyletic origin of the various eye types. The finding of well developed eyes in jellyfish which essentially lack a brain, leads us to propose that the eye as a sensory organ evolved before the brain which is an information processing organ. The finding of highly developed eyes with a lens, vitreous body, stacked membranes like a retina and shielding pigment in unicellular dinoflagellates, raises the possibility that the prototypic eyes might have been acquired from symbionts.Mol Biol Evol. 2001 Dec;18(12):2270-9. Related Articles, LinksFunctional diversification of lepidopteran opsins following gene duplication.Briscoe AD.Department of Molecular and Cellular Biology, University of Arizona, USA. adriana.briscoe@uchsc.eduA comparative approach was taken for identifying amino acid substitutions that may be under positive Darwinian selection and are correlated with spectral shifts among orthologous and paralogous lepidopteran long wavelength-sensitive (LW) opsins. Four novel LW opsin fragments were isolated, cloned, and sequenced from eye-specific cDNAs from two butterflies, Vanessa cardui (Nymphalidae) and Precis coenia (Nymphalidae), and two moths, Spodoptera exigua (Noctuidae) and Galleria mellonella (Pyralidae). These opsins were sampled because they encode visual pigments having a naturally occurring range of lambda(max) values (510-530 nm), which in combination with previously characterized lepidopteran opsins, provide a complete range of known spectral sensitivities (510-575 nm) among lepidopteran LW opsins. Two recent opsin gene duplication events were found within the papilionid but not within the nymphalid butterfly families through neighbor-joining, maximum parsimony, and maximum likelihood phylogenetic analyses of 13 lepidopteran opsin sequences. An elevated rate of evolution was detected in the red-shifted Papilio Rh3 branch following gene duplication, because of an increase in the amino acid substitution rate in the transmembrane domain of the protein, a region that forms the chromophore-binding pocket of the visual pigment. A maximum likelihood approach was used to estimate omega, the ratio of nonsynonymous to synonymous substitutions per site. Branch-specific tests of selection (free-ratio) identified one branch with omega = 2.1044, but the small number of substitutions involved was not significantly different from the expected number of changes under the neutral expectation of omega = 1. Ancestral sequences were reconstructed with a high degree of certainty from these data. Reconstructed ancestral sequences revealed several instances of convergence to the same amino acid between butterfly and vertebrate cone pigments, and between independent branches of the butterfly opsin tree that are correlated with spectral shifts.Bioessays. 2001 Sep;23(9):763-6. Related Articles, LinksMaster regulatory genes; telling them what to do.Baker NE.Department of Molecular Genetics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA. baker@aecom.yu.eduIn 1995, the eyeless (ey) gene was dubbed the "master-regulator" of eye development in Drosophila. Not only is ey required for eye development, but its misexpression can convert many other tissues into eye, including legs, wings and antennae.(1) ey is remarkable for its ability to drive coordinate differentiation of the multiple cell types that have to differentiate in a very precise pattern to construct the fly eye, and for its power to override the previous differentiation programs of many other diverse tissues. Even more remarkable, the ey homolog Pax6 and homologs of other eye determination genes from Drosophila are also required for eye development in vertebrates,(2,3) prompting reassessment of the evolution of vision throughout the animal kingdom.(4,5) Now Kumar and Moses have published a study that throws a new light on ey function in Drosophila.(6) According to their work, ey becomes a master regulator of eye development much later than previously thought, and is regulated by signalling through the Notch and EGFR signaling pathways. Copyright 2001 John Wiley & Sons, Inc.J Bacteriol. 1992 Nov;174(22):7352-9. Related Articles, LinksIsolation and characterization of a light-sensitive mutant of Escherichia coli K-12 with a mutation in a gene that is required for the biosynthesis of ubiquinone.Nakahigashi K, Miyamoto K, Nishimura K, Inokuchi H.Department of Biophysics, Faculty of Science, Kyoto University, Japan.Cells with a novel mutation that is lethal when the cells are exposed to visible light were isolated from Escherichia coli K-12. The mutation was mapped at 63 min on the linkage map of the E. coli chromosome, and the gene, designated visB, was cloned and sequenced. From its map position and the evidence that the gene product VisB exhibits homology with flavin monooxygenase of Pseudomonas fluorescens, the visB gene was deduced to be identical to the ubiH gene, which is a gene required for the biosynthesis of ubiquinone and is thought to be similar to the gene for flavin monooxygenase. The photosensitive phenotype appears to be due to the accumulation of the substrate for the reaction catalyzed by the visB (ubiH) gene product because other mutations that block earlier steps in the biosynthesis of ubiquinone can reverse the photosensitivity. The accumulated intermediates may produce active species of oxygen in the mutant bacteria upon illumination by visible light, and these active oxygen species may cause the death of the cells by a mechanism similar to that associated with mutations in visA (hemH).

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At least you got me convinced you still have a monkey-like brain in you, but let's clear this one up for you. My example was only to demonstrate the improbability of positive mutations. Evolution has no goal, that is what all evo's say. It's power lies in random mutations. Well, here's the buzz: the chance alone that random mutations in the DNA of some organism will create a light-sensitive spot is already as IMPROBABLE as a monkey that builds a computer out of rubbish, whithout ever having seen one. Understand it now? And I never mentioned anything about a computer building monkeys.

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And only an idiot would claim that arguing from personal incredulity has any merit.

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I don't state the brain is useless without the eye, but if there would have been a part of the brain that is able to translate the signals coming from the eye, while there is no eye, that brain-part or vision-processor is useless. See my point?

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Jellyfish and various metazoans get along fine with eyes and no brains...it appears you manage fine as well with eyes and no brain

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Of course you may keep thinking that gradual increasing organs lead to things like sight, but even I don't believe in Santa Clause any more... After reading some interesting books on the subject and discussing it with other people like you, I'm convinced that evolution doesn't work.

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Did these books have pictures that you were supposed to color in with crayons? It certainly does not appear that you have read anything about evolution from your clearly tenuous grasp of the subject.

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It's not a proven fact, as some people like to state. It's really just a NON-scientific THEORY.

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Care to define what a scientific theory is? This should be good

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Micro-evolution" does occur, that's right.

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If according to you there are no "positive" mutations then how can micro evolution occur? Define micro evolution...are a lot of mutations over a long period of time micro or macro?

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We see various types of cats: all mutations of some sort of pre-cat.

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Which type of pre-cat is Smilodon relative to say Felis leo? I love how specific your definitions and terminology are...must come from having read all those books.

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But do you notice any change in upward direction (increased complexity)?

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No there is no direction...that is why there are species of frogs with larger and more complex genomes than humans. Upward direction...LOL!Before you come onto a website and make statements like this

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At least you got me convinced you still have a monkey-like brain in you

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..you might want to be sure you yourself have the capactiy to back up your silly assertions....for someone with the handle "infinity" your knowledge seems to be extremely finite.[This message has been edited by Mammuthus, 01-15-2004]

What we are seeing here from Joralex is the careful construction of a straw man argument. Note the way he either ignores evidence of early visual detection systems or alternatively denigrates them as not being "proper" sight, and continually refers to complex visual systems such as the hermit crab. What he is attempting to do is, by the careful use of semantics and sophistry, to exclude precursor systems and attempt to force us to debate the concept that visual systems arose fully formed.I at least, am not buying it.Joralex, you stated that the evolution of a visual system was impossible in principle.You have been given an easily attainable mechanism for this.Address the point or withdraw.

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You people attempt to analyze this problem via a reductionist-type analysis; i.e., you believe that if you can explain a grain of sand then you will be able to explain the building. Sorry, it won't work. But, of course, you will insist that it does work since this is part of your belief system - materialistic Naturalism. This is where the crux of our disagreement lies.

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Of course we use reductionist methods. Can you name a single philosophical tool that has been more effective.For millenia philosphers and thinkers used non-reductionist tools, and many still do, to no practical avail.Science (and other disciplines employing these tools), using reductionist methods, has advanced the sphere of human knowledge immensly in just a few centuries using reductionism.

I: But do you notice any change in upward direction (increased complexity)?M: No there is no direction...that is why there are species of frogs with larger and more complex genomes than humans. Upward direction...LOL!*sigh* What I mean to say is that we don't see any drastical changes in organisms like reptiles that accidentally get wings. Maybe this is too difficult for you to onderstand but if you would look at some evolutionist-pictures of 'how life could have evolved' you could understand my point about upward change and increased complexity.As I already said, I'm aware of the statement that "evolution has no direction" but as every evolutionist believes that life started with simple organisms, you mustn't deny the fact that you need an upward change (so that is from not complex to extremely complex) to get from organisms with only one cell to organisms with billions of them.It's that upward change that I want to discuss. So let's get to the point: there's no proof of any upward change, just stating that it takes millions of years doesn't prove anything either. Oops it does, it proves the fact that the evolutionist admits that it's all VERY improbable. Show me a single animal that is evolving and I'll believe your theory. Mutations lead to changes, mostly it means a loss of something. But sometimes a loss means an advantage for the animal (take the white animals that live in areas with a lot of snow, they actually LOST their color but it gives them an advantage so that the species remain. So changes do occur, mostly it's losses. An organism can never achieve something like an eye throug mutations. Unless you're wearing thick evolution-glasses you'd see that is a fact.One last thing, can you explain your point about the jellyfish having a 'light-sensitive spot'? I've never heard of it so I'm interested to see if it is indeed a proof of eye-evolution.About the monkey-like brain, don't take that serious.. I don't take you serious either. I was just making fun. Still don't understand why you guys actually think your grand-grandfather was some sort of a monkey... the missing link-counter is still on zero, just to let you know. But we're getting off-topic now. Sorry.I'll reply to your other questions later.Infinity[This message has been edited by Infinity, 01-15-2004]

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Show me a single animal that is evolving and I'll believe your theory.

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That's like saying show me glass drip and I'll believe you when you say it's a liquid.

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Unless you're wearing thick evolution-glasses you'd see that is a fact.

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Yes, glasses, those things you need to wear because God sucked at designing eyes. Or maybe it's because humans that are near-sighted survive and have babies since we don't live in the wild any more, we have no predators to kill off our weaker blind brothers, or maybe because the time in which most people need glasses (50s onwards) they've already procreated and passed on their "endurance deficient eye gene".So does God suck at design? Or what?

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Still don't understand why you guys actually think your grand-grandfather was some sort of a monkey... the missing link-counter is still on zero, just to let you know.

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No dude, my grand-grand father was a human, he was a policeman in Sydney. Evolution takes more than three generations... My Great x 180'000 grandfather was an Australopithecus though, but he wasn't a monkey, and he wasn't a human either... he was an Australopithecus. There are no missing links? They what are all those "monkey" skulls those people dug up? God's failed experiments?[This message has been edited by AstroBlue, 01-15-2004]

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*sigh* What I mean to say is that we don't see any drastical changes in organisms like reptiles that accidentally get wings. Maybe this is too difficult for you to onderstand but if you would look at some evolutionist-pictures of 'how life could have evolved' you could understand my point about upward change and increased complexity.

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As I already said, I'm aware of the statement that "evolution has no direction" but as every evolutionist believes that life started with simple organisms, you mustn't deny the fact that you need an upward change (so that is from not complex to extremely complex) to get from organisms with only one cell to organisms with billions of them.

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Except that the most abundant life on the planet are still "simple" organisms like bacteria (which have evolved a great deal themselves). We can even watch them do it over thousands of generations.Cooper VS, Bennett AF, Lenski RE. Related Articles, Links
Evolution of thermal dependence of growth rate of Escherichia coli populations during 20,000 generations in a constant environment.
Evolution Int J Org Evolution. 2001 May;55(5):889-96.And low and behold, they even see "positive" adaptive mutations appear and spread in the population which you claim is impossible.As for going from simple organisms to complex or increasingly divergent morphological phenotype, the basis of the evolution of these processes beings studied by developmental biologists or did you happen to miss in all your extensive reading any reference to Hox genes?Only the ignorants of the creationist movement would claim that fully developed wings appear in reptiles by accident...care to inform yourself about wing development and evolution or will you stick to your cartoonish strawman?

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It's that upward change that I want to discuss. So let's get to the point: there's no proof of any upward change, just stating that it takes millions of years doesn't prove anything either. Oops it does, it proves the fact that the evolutionist admits that it's all VERY improbable. Show me a single animal that is evolving and I'll believe your theory.

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Look at the paper I cited, the bacteria are evolvingthese as well
Verheyen E, Salzburger W, Snoeks J, Meyer A. Related Articles, Links
Origin of the superflock of cichlid fishes from Lake Victoria, East Africa.
Science. 2003 Apr 11;300(5617):325-9.However, you seem to have a rather esoteric and misinformed view of evolution so I can foresee that any example of evolution or speciation that I provide will be dismissed.

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Mutations lead to changes, mostly it means a loss of something. But sometimes a loss means an advantage for the animal (take the white animals that live in areas with a lot of snow, they actually LOST their color but it gives them an advantage so that the species remain. So changes do occur, mostly it's losses.

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There are losses, their are gains, and their are neutral mutations. You claim taht their is only loss or mostly loss...care to show the scientific studies that support this assertion or like your other supposed evidence for your statements, you make it based on ignorance?

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An organism can never achieve something like an eye throug mutations. Unless you're wearing thick evolution-glasses you'd see that is a fact.

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Actually I put on my glasses, read, do experiments, and study every day so that I don't have to let personal incredulity determine the limits of my knowledge. Eye evolution is actually fairly intensively studied....let me guess, you have never read a single scientific article on the subject? In fact, my guess is that you don't even know what the theory of evolution actually is.

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One last thing, can you explain your point about the jellyfish having a 'light-sensitive spot'? I've never heard of it so I'm interested to see if it is indeed a proof of eye-evolution.

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actually I said that jellyfish have complex eyesDev Cell. 2003 Nov;5(5):773-85. Related Articles, LinksRole of Pax genes in eye evolution: a cnidarian PaxB gene uniting Pax2 and Pax6 functions.Kozmik Z, Daube M, Frei E, Norman B, Kos L, Dishaw LJ, Noll M, Piatigorsky J.Laboratory of Molecular and Developmental Biology, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA.PaxB from Tripedalia cystophora, a cubomedusan jellyfish possessing complex eyes (ocelli), was characterized. PaxB, the only Pax gene found in this cnidarian, is expressed in the larva, retina, lens, and statocyst. PaxB contains a Pax2/5/8-type paired domain and octapeptide, but a Pax6 prd-type homeodomain. Pax2/5/8-like properties of PaxB include a DNA binding specificity of the paired domain, activation and inhibitory domains, and the ability to rescue spa(pol), a Drosophila Pax2 eye mutant. Like Pax6, PaxB activates jellyfish crystallin and Drosophila rhodopsin rh6 promoters and induces small ectopic eyes in Drosophila. Pax6 has been considered a "master" control gene for eye development. Our data suggest that the ancestor of jellyfish PaxB, a PaxB-like protein, was the primordial Pax protein in eye evolution and that Pax6-like genes evolved in triploblasts after separation from Cnidaria, raising the possibility that cnidarian and sophisticated triploblastic eyes arose independently.and that they do not require a brain for processing complex images as you assert is necessary.

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About the monkey-like brain, don't take that serious.. I don't take you serious either

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You should take your lack of knowledge about a subject you claim to so vehemently oppose seriously.

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Still don't understand why you guys actually think your grand-grandfather was some sort of a monkey

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My metarnal great grandfathers were spanish, paternal side Welsh and German. And no, we shared a common ancestor with chimpanzees...we did not pop out of a monkey de novo....that would be creationist logic and a typical creationist strawman that those who are too lazy to actually learn what science has to say put up all the time.

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I'll reply to your other questions later.

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Hopefully with evidence to support your assertions.

Even more on eye evolution i.e. does not require many novel genes for eye formation to occur...and there is even information on how the key genes formed from even older ancestral genesDev Genes Evol. 1998 Aug;208(6):352-6. Related Articles, LinksPax-6 origins--implications from the structure of two coral pax genes.Catmull J, Hayward DC, McIntyre NE, Reece-Hoyes JS, Mastro R, Callaerts P, Ball EE, Miller DJ.Department of Biochemistry and Molecular Biology, James Cook University, Townsville, Queensland 4811, Australia.Vertebrate Pax-6 and its Drosophila homolog eyeless play central roles in eye specification, although it is not clear if this represents the ancestral role of this gene class. As the most "primitive" animals with true nervous systems, the Cnidaria may be informative in terms of the evolution of the Pax gene family. For this reason we surveyed the Pax gene complement of a representative of the basal cnidarian class (the Anthozoa), the coral Acropora millepora. cDNAs encoding two coral Pax proteins were isolated. Pax-Aam encoded a protein containing only a paired domain, whereas Pax-Cam also contained a homeodomain clearly related to those in the Pax-6 family. The paired domains in both proteins most resembled the vertebrate Pax-2/5/8 class, but shared several distinctive substitutions. As in most Pax-6 homologs and orthologs, an intron was present in the Pax-Cam locus at a position corresponding to residues 46/47 in the homeodomain. We propose a model for evolution of the Pax family, in which the ancestor of all of the vertebrate Pax genes most resembled Pax-6, and arose via fusion of a Pax-Aam-like gene (encoding only a paired domain) with an anteriorly-expressed homeobox gene resembling the paired-like class.As to the impossibility of a mutation leading to a novel developmental process as you suggest,one example that refutes this is Syncytin, an envelope gene of an endogenous retrovirus that is critical for syncytiotrophoblast formation in old world monkeys through humans but not in other placental mammals...mutation lead to novel developmental properties critical for placental formation...a positive thing since no placenta = extinction.Another example of mutation adding to complexityare Hox gene cluster duplications from a single cluster in a very simple primitive organism like amphioxous to the multiple Hox gene clusters and greater morphological complexity in Drosophila through humans.for a review of genome evolution in generalScience. 2003 Nov 21;302(5649):1401-4. Related Articles, LinksThe origins of genome complexity.Lynch M, Conery JS.Department of Biology, Indiana University, Bloomington, IN 47405, USA. mlynch@bio.indiana.eduComplete genomic sequences from diverse phylogenetic lineages reveal notable increases in genome complexity from prokaryotes to multicellular eukaryotes. The changes include gradual increases in gene number, resulting from the retention of duplicate genes, and more abrupt increases in the abundance of spliceosomal introns and mobile genetic elements. We argue that many of these modifications emerged passively in response to the long-term population-size reductions that accompanied increases in organism size. According to this model, much of the restructuring of eukaryotic genomes was initiated by nonadaptive processes, and this in turn provided novel substrates for the secondary evolution of phenotypic complexity by natural selection. The enormous long-term effective population sizes of prokaryotes may impose a substantial barrier to the evolution of complex genomes and morphologies.this is just the very tip of the iceberg infinity....you have a lot of reading to catch up on