Can sense organs like the eye really evolve?

There is no such thing as a simple eye. Trilobite eyes for example. Despite evolution claiming that trilobites are primitive creatures, research shows that they had compound eyes. 100 eyes on each side of its head. Some have four lenses on each eye so that they could see with undistorted vision. Incredible complexity and yet one of the first things found in the fossil record. If different types of eyes evolved independently, how can they be traced to a common ancestor? It also doesnt make sense to observe different types of eyes in nature and claim that they present an evolutionary sequence.

Yes there is. A simple eye is an eye which is not compound. Where is this claimed? Apart from the eyeless varieties, such as Agnostina. Who said they could? According to biologists, the eye evolved several times independently. That sentence needs the word "because" in it, followed by a further clause.

Any chance of supporting this point with evidence? It makes perfect sense to me: what is your rationale, here?

http://www.sciencedaily.com/...ases/2008/11/081119140705.htmSo only 2 cells guide the Zooplankton to the Light is this a simple enough eye for you cause i dont think it can get any simpler.

Hi Portillo, Planarian worms would disagree with you. They have simple eye spots. Showing one example of a complex eye does not render my example of a simple eye invalid. That it not a claim that I would make. "Primitive" is only meaningful in evolutionary terms when the creature in question left modern descendants. The trilobites didn't, they went extinct. And some had no eyes at all. Your point?Also, you are aware aren't you, that the three major groups of trilobite eyes fall into an nested hierarchy? And that they emerge in the fossil record only over great periods of time, just as we would expect had they evolved? This claim is straightforwardly false. Trilobites are far from the first things found in the fossil record. Ever heard of stromatolites? These fossils, left by cyanobacteria, go back at least 2 billion years, compared to the trilobites' 526 million years. Good question. Of course, I have already answered it.The commonality between eyes is obvious when you look at their construction. They are all made up of the same basic photoreceptors; ciliary and rhabdomeric. They share genes, even between distantly related groups like molluscs and planarians.What you need to understand is that the last common ancestor of all these groups would have had very primitive light-sensing abilities, likely without anything recognisable as a modern eye. After the various lineages split off, they independently took these building blocks and developed them, but each group took a slightly different path with them, leading to the diverse forms observable today. This is all entirely consistent with an evolutionary model. When we point to the eyes of a scallop and a squid and a human, and compare them, we are not suggesting that one evolved from the other. Rather, such comparisons are intended to show that each individual stage of the putative route of vertebrate eye evolution is, by itself, possible.One thing I can't help but notice is that you still haven't made it any clearer what you meant by this; I would be grateful if you could elaborate on this. What evidence exactly would you expect to see if evolution were true? What kind of "process" would you expect to see and over what kind of time-scale?I'm sorry to harp on at you, but this is an important question. How can you tell us that there's no evidence for evolution if you can't tell us what evidence we should expect evolution to leave?Mutate and SurviveEdited by Granny Magda, : No reason given.

I'm getting the sense that they really do expect for us to providing evidence of the scallop eye evolving into the squid eye and the squid eye evolving into the human eye, as if that's what the ToE suggests.I think they really are that clueless...

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It also doesnt make sense to observe different types of eyes in nature and claim that they present an evolutionary sequence.

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the different types of eyes, in an evolutionary sequence The stupid, it burns.

Hi CS,I think I might make the question "What evidence exactly would you expect to see if evolution were true?" my go to question for creationist posters and I'll tell you for why. I reckon that you'll usually see three basic responses to that question. 1) Unreasonable Demands I want to see the fossils! All of them! I want to see fossils for every single generation, for every imaginable iteration of each and every evolutionary lineage going back to the dawn of time. And I want them all to have perfectly fossilised eyes demonstrating every tiny change that took place throughout their history. I would also like the moon on a stick, served to me by a flying pig.Essentially, the creationist will demand far more evidence than we might ever hope to find. Usually they will place much less stringent requirements upon their own arguments. 2) Strawman Intermediate forms? Well then, just show me a crocoduck! Or a half-man-half-monkey!! Show me a scallop turning into a squid!!!Show me life springing from my peanut butter jar!!!! Or any number of other crazy things!!!!!!!!!!Here, the creationist demands evidence for a version of evolution that no sane biologist would recognise. These kind of demands seem to spring from severe misconceptions about what the ToE actually says. Quite often, if we were to provide this kind of evidence, we would falsify the ToE, not prove it. 3) Reasonable Demands With this one the creationist asks for reasonable evidence, that is something that is both compatible with the real ToE and is something that we might reasonably expect to be able to observe.I can't think of any illustrative examples off hand, because we so rarely get asked this kind of question on these forums. In theory though, should this happen, you could just show them the evidence.I'm not saying that this will work any better than any other approach, but it's got to be worth a shot. And if that fails, I'll just call them dumbasses and say rude things about Jesus.Mutate and Survive

I think the 'whale evolution' thread would probably count. (Sorry, CBA to find a link to it.)
But it was a notably unique thread.

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The stupid, it burns.

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The condescending attitude and insults is pathetic.

Responding to Granny Magda's Message 230 would have been far more constructive.

Hi Portillo,Moderators try to discourage insults, but in this case they seem to be born out of frustration. You posted Message 220 two weeks ago, received 5 responses, answered none. You posted Message 226 a week ago, received 4 responses, answered none. If you're going to post provocative claims like there's no such thing as a simple eye and then not respond, you've got to expect some frustration. I think the other participants are beginning to wonder if you've slipped into drive-by mode (i.e., just pass through from time to time and occasionally posting with no intention of following up).Panda's suggestion seems sound, just respond to Message 230, or at least some messages so that there can be actual discussion, and so that people understand why you would say things that, at least on the surface, seem clearly wrong.

I responded to Granny Magda twice didnt I?

So your response to a moderator message noting your lack of response to recent posts and requesting that you respond to at least some of them is to respond with a message notable for it unresponsiveness? Interesting.To repeat, Panda's suggestion seems sound, just respond to Message 230, or at least some messages so that there can be actual discussion, and so that people understand why you would say things that, at least on the surface, seem clearly wrong.Please, no replies to this message.Edited by Admin, : Minor cleanup.

I dunno bout eyes but I'm here testing my new iPad. Hope I can post stuff.

New member here, a bit of background about me before I start posting, I am a biologist that went to graduate school, all the way, and now teach in a University.Anyhow, back on topic, it seems like someone has been reading "Darwin's Blackbox". The entire argument of this book can be deconstructed if we go back in time just a little bit. Today the blackbox is the eye, 50 years ago it was the genetic code (nobody knew DNA existed), and 50 years from now we will know how the eye evolved, but there will be another blackbox.It may be true that we are missing some steps on eye evolution (or a few other things), but this by no means invalidates the Theory of Evolution. Just like missing fossils does not invalidate it. If the entire human civilization was wiped out and all that was left was a religious text from the 1500's and an iPad, extra-terrestrial creationists would certainly conclude there were two civilizations on earth.