[_ Old Earth _] The Eye: Darwin's Dilemma

[lordkalvan]

double speak.gotta love it.

laws of nature dont have a clue of what they act on. gravity doesnt think hey jason is falling lets make him fall. they just do what they do.

And yet they guide you towards the ground.....

 

[jasoncran]

And yet they guide you towards the ground.....

by that thinking then somewhere in the universe given enough time these machines typing will overpower men as we are guiding them to our own destruction.

guiding. eh.

i should do a thread in here on engineers that use cads based on the toe and the often poorly designed or placed parts on cars.

ie rubber near heat. this same rubber is vital for the suspension to work. but hey what do i expect for unguided evolution.

 

[Asyncritus]

LK

Ihave been re-reading your posts looking for 'reasoned explanations' of the phenomena I want explaining.

I must have missed them.

So to simplify matters for those of us with smaller IQs, let me ask for an explanation of one thing at a time, as opposed to two.

Here's the first.

As you rightly say, I place great store in the existence of instinct, because in my opinion, instinct is like the software in a computer. Without it, the machinery may exist, but is useless.

Unless the instincts required to power flight exist (the software), then the best wings on the planet (the hardware) are useless. The creature (bird, bat, pterosaur, insect) simply doesn't know what to with the wing now on its back or wherever.

We will assume that A doesn't have wings and that in the course of zillions of years, it 'evolves' into B which does. However many interim steps there may be (you choose), we arrive at B which can fly.

I must remind you that learned behaviour cannot be inherited. That is the roundly discredited Lamarckism.

You now have 2 problems at least, and I will trouble you for an answer to number 1.

How did the flight instincts in B arise - because arise they did - when they did not exist in A?

Thank you.

 

[lordkalvan]

LK

Ihave been re-reading your posts looking for 'reasoned explanations' of the phenomena I want explaining.

I must have missed them.

So to simplify matters for those of us with smaller IQs, let me ask for an explanation of one thing at a time, as opposed to two.

Here's the first.

As you rightly say, I place great store in the existence of instinct, because in my opinion, instinct is like the software in a computer. Without it, the machinery may exist, but is useless.

Unless the instincts required to power flight exist (the software), then the best wings on the planet (the hardware) are useless. The creature (bird, bat, pterosaur, insect) simply doesn't know what to with the wing now on its back or wherever.

We will assume that A doesn't have wings and that in the course of zillions of years, it 'evolves' into B which does. However many interim steps there may be (you choose), we arrive at B which can fly.

I must remind you that learned behaviour cannot be inherited. That is the roundly discredited Lamarckism.

You now have 2 problems at least, and I will trouble you for an answer to number 1.

How did the flight instincts in B arise - because arise they did - when they did not exist in A?

Thank you.

You seem to be labouring under the delusion that a discussion is a one-way street and that you can request answers to what you seem to regard as your pivotal, evolution-falsifying questions while blithely ignoring or handwaving away every comment, point, question and argument that relates to your various assertions and assumptions (as well as the aforesaid questions - which are themselves driven by and founded upon these assertions and assumptions) as if they are wholly irrelevant and unimportant. Perhaps you would like to review your post in the light of these observations.

 

[Asyncritus]

You seem to be labouring under the delusion that a discussion is a one-way street and that you can request answers to what you seem to regard as your pivotal, evolution-falsifying questions while blithely ignoring or handwaving away every comment, point, question and argument that relates to your various assertions and assumptions (as well as the aforesaid questions - which are themselves driven by and founded upon these assertions and assumptions) as if they are wholly irrelevant and unimportant. Perhaps you would like to review your post in the light of these observations.

Having reviewed it, I find nothing unclear, non-factual or even pure assertion. (If you do find some, please point them out).

We have B(at) that flies, and A(ancestor of bat) that doesn't. Facts.

There must be (according to evolution theory), some intermediate steps. Fact.

I am not too concerned here about the evolution of the equipment (the wings), big enough a problem though that may undoubtedly be.

I am deeply concerned about the intangibles - the flight instincts. They do exist (fact), or the bat couldn't fly. I do hope you agree with that point.

Now the question before us is, how did that instinct arise in the first place?

We will ignore part b. (how did it get into the genome?) for the moment too.

Again I remind you that Lamarckism is as dead as the proverbial doornail. A hopping or leaping or gliding ancestor also had to acquire its instincts to do so from somewhere, and cannot transmit anything it has learned about flight to its offspring.

Over to you.

 

[lordkalvan]

Having reviewed it, I find nothing unclear, non-factual or even pure assertion. (If you do find some, please point them out).

Really? you have reviewed all my comments on your posts in this thread and you find no point, question or argument that relates to any assertions and assumptions or assumptions on your part?

Well, try this one:

'...those mutations, as many studies have shown, are all neutral or deleterious.'

You have not shown this, you have simply asserted it.

Here's another:

'...intelligent design is demonstrated by the existence of 3 elements.

Again, you have simply asserted this to be so, but failed to show why these '3 elements' demostrate intelligent design at all. And one more:

'The Designer knew about light scattering, and specifically prevented it. He knew about lenses, their required curvature, and the aberrations that such lenses produced.'

This assertion is based solely on personal incredulity that naturalistic processes could lead to anything as potentially complex as they eye,

We have B(at) that flies, and A(ancestor of bat) that doesn't. Facts.

There must be (according to evolution theory), some intermediate steps. Fact.

I am not too concerned here about the evolution of the equipment (the wings), big enough a problem though that may undoubtedly be.

Why is this a big problem?

I am deeply concerned about the intangibles - the flight instincts. They do exist (fact), or the bat couldn't fly. I do hope you agree with that point.

Now the question before us is, how did that instinct arise in the first place?

Instincts reside in the genes. An organism is a whole, not a series of discrete bits that function independently of each other. Why do you suppose that behaviour/instinct and physical traits do not interact?

We will ignore part b. (how did it get into the genome?) for the moment too.

Again I remind you that Lamarckism is as dead as the proverbial doornail. A hopping or leaping or gliding ancestor also had to acquire its instincts to do so from somewhere, and cannot transmit anything it has learned about flight to its offspring.

Over to you.

And I remind you again that this is not a one-way street. Do you have any response at all to any of the points, arguments, comments and questions I have made, or do you simply intend to continue ignoring them?

 

[Asyncritus]

Really? you have reviewed all my comments on your posts in this thread and you find no point, question or argument that relates to any assertions and assumptions or assumptions on your part?

Well, try this one:

'...those mutations, as many studies have shown, are all neutral or deleterious.'

You have not shown this, you have simply asserted it.

Try google on 'mutations'. Find a few beneficial ones if you dispute my 'assertions'.

“But mutations are found to be of a random nature, so
far as their utility is concerned. Accordingly, the great
majority of mutations, certainly well over 99%, are harmful in some way, as is to be expected of the effects of
accidental occurrences.”—*H.J. Muller, “Radiation
Damage to the Genetic Material,” in American Scientist,
January 1950, p. 35.

Here's another:

'...intelligent design is demonstrated by the existence of 3 elements.

Again, you have simply asserted this to be so, but failed to show why these '3 elements' demostrate intelligent design at all. And one more:

You need to read Dembski on the point. Try Intelligent Design pub IVP.

'The Designer knew about light scattering, and specifically prevented it. He knew about lenses, their required curvature, and the aberrations that such lenses produced.'

This assertion is based solely on personal incredulity that naturalistic processes could lead to anything as potentially complex as they eye,

Is this the extent of your 'proof'/ evidence? Tut, man.

Why is this a big problem?

Why is this a big problem? Because there is no evdence for any such organ 'evolving' in the bats. If you know of any, please let us know.

But they must have come from somewhere. What does evolution say about that?

Instincts reside in the genes. An organism is a whole, not a series of discrete bits that function independently of each other. Why do you suppose that behaviour/instinct and physical traits do not interact?

And here you beg the question totally.

Instinct may reside in the genes. That is a moot point. But assuming it does. The question which you ignore, is still here, and I will not let it go away.

Using flight in the bat as our example, how did those instincts arise, and how did they get into the genome?

And I remind you again that this is not a one-way street. Do you have any response at all to any of the points, arguments, comments and questions I have made, or do you simply intend to continue ignoring them?

And I remind you that I started this thread, posed the questions you now know so well, and am still awaiting some answers. I claim precedence and priority by virtue of being first in the field.

So please don't ignore the questions which we started off with. Remember, 'I don't know' is an acceptable response, but as I say, it opens a huge can of worms which will devour evolution.

 

[EricTheBaptist]

Darwin claims that the eye is too complicated to have evolved but also remember that we have gained more knowledge from Darwin's time. He didn't have DNA or any other resource available to him.

 

[Asyncritus]

Darwin claims that the eye is too complicated to have evolved but also remember that we have gained more knowledge from Darwin's time. He didn't have DNA or any other resource available to him.

Perfectly true Eric.

And the more we know and find out, the bigger the problems for evolution become!

You mentioned DNA. Have you ever had a look at how it's made up and how it works? If that doesn't shut down any evolution theory, I don't know what does.

I remember a mathematician writing words to the effect that the day that the structure of DNA was announced, was the day that all arguments about evolution were finished.

Of course, nothing will kill this theory. It's too convenient a bolt hole for those who have no inclinations to worship God, or who are opposed to doing so.

 

[lordkalvan]

Try google on 'mutations'. Find a few beneficial ones if you dispute my 'assertions'.

You are supposed to support your own assertions, not expect others to refute them. But since you ask, here's one:

'Although most mutations that change protein sequences are neutral or harmful, some mutations have a positive effect on an organism. In this case, the mutation may enable the mutant organism to withstand particular environmental stresses better....

For example, a specific 32 base pair deletion in human CCR5 (CCR5-Δ32) confers HIV resistance to homozygotes and delays AIDS onset in heterozygotes.[44] The CCR5 mutation is more common in those of European descent.'

Source: en. wikipedia.org/wiki/Mutation

You may also want to consider whether antibiotic resistance in bacteria is a beneficial mutation (for bacteria) or not.

“But mutations are found to be of a random nature, so
far as their utility is concerned. Accordingly, the great
majority of mutations, certainly well over 99%, are harmful in some way, as is to be expected of the effects of
accidental occurrences.”—*H.J. Muller, “Radiation
Damage to the Genetic Material,” in American Scientist,
January 1950, p. 35.

Do you have a reference a little more recent that six decades old and that does not so obviously seem to be addressing damaging agents introduced into the environment by ourselves, in this case ionizing radiation? Radiation-caused mutations may be overwhelmingly harmful, but this does not show that in general all mutations are overwhelmingly harmful. Did you source this reference from a creationist website, just out of interest?

You need to read Dembski on the point. Try Intelligent Design pub IVP.

So that's no, you can't tell us why these '3 elements' demonstrate intelligent design at all.

Is this the extent of your 'proof'/ evidence? Tut, man.

Umm, it's your evidence we're addressing here; I am pointing out that you have simply asserted that 'The Designer knew about light scattering, and specifically prevented it. He knew about lenses, their required curvature, and the aberrations that such lenses produced' while offering nothing but personal incredulity that naturalistic processes could lead to anything as potentially complex as they eye.

Why is this a big problem? Because there is no evdence for any such organ 'evolving' in the bats. If you know of any, please let us know.

Again you seem to be laboring under the misapprehension that, because the fossil record for bats is at present fragmentary, the absence of this fossil evidence constitutes a major hurdle for evolutionary theory. It doesn't, simply because the robustness of evolutionary theory is not dependent upon whether or not we have a complete account of how bat wings evolved. Regardless of this, however, we can look at the existence and utility (or otherwise) of wings in birds that cannot fly to determine whether or not wing-like structures have any function that is not associated with flying. If this is the case, and it is, it is a reasonable inference to make that exaptation can lead to these structures gaining other functions. From this inference it is a simple step to hypothesizing the development of bat-flight from a non-flying or gliding ancestor, to look for molecular genetic evidence that places bats amongst the group of animals with which it shared a common ancestral species and to search for fossil evidence that may support our hypothesis.

But they must have come from somewhere. What does evolution say about that?

The same that it says about the development of any trait or suite of traits.

And here you beg the question totally.

Instinct may reside in the genes. That is a moot point.

Why is it moot? What evidence do you have that instinct does not reside in the genes? From your comments, you appear to believe that instincts like these are inherited; the only mechanism for inheritance that we are aware of is the genes. Therefore instincts are transmitted genetically. The Sanger Institute, for example, studies mice to determine 'the genes and pathways that underpin instinctive behaviour' (www. sanger.ac.uk/research/projects/geneticsofinstinctivebehaviour/).

But assuming it does. The question which you ignore, is still here, and I will not let it go away.

Using flight in the bat as our example, how did those instincts arise, and how did they get into the genome?

By positive feedback. Protowings are useful for at least two things: they can regulate temperature and they can aid balance. If you want to know what instinct 'powers' wings, you need to keep stepping back: what instinct 'powers' your arms and, if you lose your balance (or fall), why do you flap your arms? Ultimately, you will have to address the question of what led to the development of motility in single-celled organisms.

And I remind you that I started this thread, posed the questions you now know so well, and am still awaiting some answers. I claim precedence and priority by virtue of being first in the field.

And I have addressed your questions and arguments with relevant points, comments, counter-arguments and questions which you have largely ignored or handwaved away. Simply because you provided the OP does not excuse you from the obligation, if you wish to seriously discuss the subject (which seems to be increasingly doubtful), of responding to those points arising from your own posts.

So please don't ignore the questions which we started off with.

And I have not ignored those questions, I have endeavoured to open up the conversation around the very limited perspective and understanding that those questions imply.

Remember, 'I don't know' is an acceptable response, but as I say, it opens a huge can of worms which will devour evolution.

And you need to understand that 'I don't know' does no such thing. The only thing that 'will devour evolution' is evidence that will falsify it. I would have thought that, with your scientific background, you would have known this already.

 

[EricTheBaptist]

Perfectly true Eric.

And the more we know and find out, the bigger the problems for evolution become!

You mentioned DNA. Have you ever had a look at how it's made up and how it works? If that doesn't shut down any evolution theory, I don't know what does.

I remember a mathematician writing words to the effect that the day that the structure of DNA was announced, was the day that all arguments about evolution were finished.

Of course, nothing will kill this theory. It's too convenient a bolt hole for those who have no inclinations to worship God, or who are opposed to doing so.

How would DNA shut the theory down? That would boost how well of a standing it is.

 

[Asyncritus]

How would DNA shut the theory down? That would boost how well of a standing it is.

Pretty simply.

Such a device could not have evolved. There is no possibility that it could either.

Therefore, right at the bottom of the evolutionary heap, is something (DNA) that could not have evolved. If the foundation is gone, then the building collapses in a heap.

Have a look too, at my post on mitosis. Think how that could not have evolved - and then ask, what are they talking about?

I'm putting up one about meiosis next. That's even more startling and amazing. Get LK to account for that if he can.

 

[lordkalvan]

Pretty simply.

Such a device could not have evolved.

And your evidence is what? A misunderstanding of chemical reactions and the consequences of countless millions of events occurring almost simultaneously?

There is no possibility that it could either.

Can you actually demonstrate this with something other than pseudomaths?

Therefore, right at the bottom of the evolutionary heap, is something (DNA) that could not have evolved.

You have not established this, you have simply asserted it on the back of some rather large assumptions.

If the foundation is gone, then the building collapses in a heap.

Well, no. Just for the purposes of argument, some supernatural intelligence (aka God) could have created the first single-celled life-form within which was the primordial DNA. From this single-celled life-form all other organisms with which we are familiar have evolved.

Have a look too, at my post on mitosis. Think how that could not have evolved - and then ask, what are they talking about?

Looks like another helping of pseudomaths, a misunderstanding of evolutionary theory as a theory of chance (it isn't) and a few more unsupported assumptions.

I'm putting up one about meiosis next. That's even more startling and amazing. Get LK to account for that if he can.

Well, if it's like the other one, I would imagine it will be based on the same shaky ideas and misunderstandings.

 

[Barbarian]

Such a device could not have evolved. There is no possibility that it could either.

Turns out, it did. The first known trilobites lacked eyes. Later ones had relatively simple holochroal eye, consisting of many lenses packed in a hexagonal array with a single membrane.

The schizochroal eye, with relatively few, more complex lenses, was easily evolved from the holochroal eye by paedomorphosis.

All early trilobites (Cambrian), had holochroal eyes and it would seem hard to evolve the distinctive phacopid schizochroal eye from this form. The answer is thought to lie in ontogenetic (developmental) processes on an evolutionary time scale. Paedomorphosis is the retention of ancestral juvenile characteristics into adulthood in the descendent. Paedomorphosis can occur three ways: Progenesis (early sexual maturation in an otherwise juvenile body), Neoteny (reduced rate of morphological development), and Post-displacement (delayed growth of certain structures relative to others). The development of schizochroal eyes in phacopid trilobites is a good example of post-displacement paedomorphosis. The eyes of immature holochroal Cambrian trilobites were basically miniature schizochroal eyes. In Phacopida, these were retained, via delayed growth of these immature structures (post-displacement), into the adult form.
The Trilobite Eye

Therefore, right at the bottom of the evolutionary heap, is something (DNA) that could not have evolved. If the foundation is gone, then the building collapses in a heap.

Not this time, at least. Ignorance is the enemy. Knowledge will lead you to the truth.

Have a look too, at my post on mitosis. Think how that could not have evolved - and then ask, what are they talking about?

The evolution of mitosis and the eukaryotic condition.
J Pickett-Heaps - Bio Systems, 1974 - ncbi.nlm.nih.gov
1. Biosystems. 1974 Jul;6(1):37-48. The evolution of mitosis and the eukaryotic condition.

I'm putting up one about meiosis next. That's even more startling and amazing. Get LK to account for that if he can.

Turns out that one isn't that hard to see, either:

Origins of Life and Evolution of Biospheres
Volume 13, Numbers 3-4, 183-193, DOI: 10.1007/BF00927170
From proto-mitosis to mitosis — An alternative hypothesis on the origin and evolution of the mitotic spindle

U. -P. Roos


Based on the assumption that the ancestral proto-eukaryote evolved from an ameboid prokarybte I propose the hypothesis that nuclear division of the proto-eukaryote was effected by the same system of contractile filaments it used for ameboid movement and cytosis. When the nuclear membranes evolved from the cell membrane, contractile filaments remained associated with them. The attachment site of the genome in the nuclear envelope was linked to the cell membrane by specialized contractile filaments. During protomitosis, i.e., nuclear and cell division of the proto-eukaryote, these filaments performed segregation of the chromosomes, whereas others constricted and cleaved the nucleus and the mother cell. When microtubules (MTs) had evolved in the cytoplasm, they also became engaged in nuclear division. Initially, an extranuolear bundle of MTs assisted chromosome segregation by establishing a defined axis. The evolutionary tendency then was towards an increasingly important role for MTs. Spindle pole bodies (SPBs) developed from the chromosomal attachment sites in the nuclear envelope and organized an extranuclear central spindle. The chromosomes remained attached to the SPBs during nuclear division. In a subsequent step the spindle became permanently lodged inside the nucleus. Chromosomes detached from the SPBs and acquired kinetochores and kinetochore-MTs. At first, this spindle segregated chromosomes by elongation, the kinetochore-MTs playing the role of static anchors. Later, spindle elongation was supplemented by poleward movement of the chromosomes. When dissolution of the nuclear envelope at the beginning of mitosis became a permanent feature, the open spindle of higher eukaryotes was born.

 

[Asyncritus]

Turns out, it did. The first known trilobites lacked eyes. Later ones had relatively simple holochroal eye, consisting of many lenses packed in a hexagonal array with a single membrane.

Hold it right there pal. So the eyes, of whatever sort, just 'appeared' did they? Of course they did! Just wave the happy wand of imaginativeness, and anything is possible, isn't it? Yes, of course it is.

The schizochroal eye, with relatively few, more complex lenses, was easily evolved from the holochroal eye by paedomorphosis.

Let's wave the wand again, shall we? 'Easily evolved' indeed. Of course. What else can we expect? That deity, evolution, can do all things, can't it?

All early trilobites (Cambrian), had holochroal eyes and it would seem hard to evolve [No, no pal. I've got news for you. It IS hard - no, impossible]the distinctive phacopid schizochroal eye from this form. The answer is thought to lie in ontogenetic (developmental) processes on an evolutionary time scale.

Yes, of course. Given enough billion years, anything's possible, isn't it?Like hell it is.

Paedomorphosis is the retention of ancestral juvenile characteristics into adulthood in the descendent.


Paedomorphosis can occur three ways: Progenesis (early sexual maturation in an otherwise juvenile body), Neoteny (reduced rate of morphological development), and Post-displacement (delayed growth of certain structures relative to others).

If you want a good laugh, go read the wiki article on paedomorphosis. Bet you didn't know that Betty Boop is a great example of it? Neoteny - Wikipedia, the free encyclopedia

The development of schizochroal eyes in phacopid trilobites is a good example of post-displacement paedomorphosis. The eyes of immature holochroal Cambrian trilobites were basically miniature schizochroal eyes.

Oh yeah. So the IMMATURE, simpler beasts had these wonderful eyes, did they? Does it ever occur to you to ask some questions round about here, B? Like, um, where did these immature critters get such remarkable things?

It sounds as if the EARLIER creatures were more highly 'evolved'. Do you agree? And are we on the verge of some stunning nonsense? Again?

In Phacopida, these were retained, via delayed growth of these immature structures (post-displacement), into the adult form.

You really should read these articles you quote with a bit more thoughtfulness, B. See the word RETAINED? Know what it means? I'm sure you do.

But just in case it may have slipped your mind, let me remind you: it ALREADY EXISTED, and was NOT LOST.

See (heh heh!) the problem?
The Trilobite Eye

Not this time, at least. Ignorance is the enemy. Knowledge will lead you to the truth.

I'm afraid this article you've quoted demonstrates stupidity, rather than ignorance. Maybe a combination of both.

The evolution of mitosis and the eukaryotic condition.
J Pickett-Heaps - Bio Systems, 1974 - ncbi.nlm.nih.gov
1. Biosystems. 1974 Jul;6(1):37-48. The evolution of mitosis and the eukaryotic condition.


Turns out that one isn't that hard to see, either:

Origins of Life and Evolution of Biospheres
Volume 13, Numbers 3-4, 183-193, DOI: 10.1007/BF00927170
From proto-mitosis to mitosis — An alternative hypothesis on the origin and evolution of the mitotic spindle

U. -P. Roos


Based on the assumption that the ancestral proto-eukaryote evolved from an ameboid prokarybte I propose the hypothesis that nuclear division of the proto-eukaryote was effected by the same system of contractile filaments it used for ameboid movement and cytosis.

Excuse me, but don't I hear a loud piece of question begging here?

When the nuclear membranes evolved [QB, QB, QB!!!] from the cell membrane,

Such nonsense! Doesn't this guy know, and don't you either, about such material as this:"One of the great mysteries in biology is the origin of cell membranes, the protective layers that completely surround the complex chemical soup in which many of life's most delicate processes take place."I think Monod and Chain said pretty much the same thing, but I can't lay my hands on the quotations offhand. I will if you like, look them up.

contractile filaments remained associated with them. The attachment site of the genome in the nuclear envelope was linked to the cell membrane by specialized contractile filaments.

Since we have no real idea of how cell mambranes were produced/evolved, don't you think this is another pece of rank question-begging? He has not asked fundamental questions, and you ought to be asking them too, instead of merely swallowing this guff.

During protomitosis, i.e., nuclear and cell division of the proto-eukaryote, these filaments performed segregation of the chromosomes, whereas others constricted and cleaved the nucleus and the mother cell.

There, isn't that marvellous? Anybody can see that that is exactly how it happened! Like hell!You got any idea WHY it happened? Where the necessary information/instincts came from? No? I didn't think so.

When microtubules (MTs) had evolved in the cytoplasm,

Heh heh heh!

they also became engaged in nuclear division. Initially, an extranuolear bundle of MTs assisted chromosome segregation by establishing a defined axis. The evolutionary tendency then was towards an increasingly important role for MTs. Spindle pole bodies (SPBs) developed from the chromosomal attachment sites in the nuclear envelope and organized an extranuclear central spindle. The chromosomes remained attached to the SPBs during nuclear division. In a subsequent step the spindle became permanently lodged inside the nucleus. Chromosomes detached from the SPBs and acquired kinetochores and kinetochore-MTs. At first, this spindle segregated chromosomes by elongation, the kinetochore-MTs playing the role of static anchors.

Wowee!

Later, spindle elongation was supplemented by poleward movement of the chromosomes. When dissolution of the nuclear envelope at the beginning of mitosis became a permanent feature, the open spindle of higher eukaryotes was born.

You don't say!

Yadda yadda yadda. Shall I comment further, or have I made the point that this is really polysyllabic garbage?

You really ought, as I've said, to read with some thought, and cite more carefully - after considering some of the questionable assumptions and implications of what is being said.

Because it's in a PAPER (wahey!) in some journal somewhere, doesn't mean that it isn't nonsense, you know.

 

[Barbarian]

Barbarian observes:
Turns out, it did. The first known trilobites lacked eyes. Later ones had relatively simple holochroal eye, consisting of many lenses packed in a hexagonal array with a single membrane.

Hold it right there pal. So the eyes, of whatever sort, just 'appeared' did they?

No. The first trilobites we know about had no eyes, and then very simple ones. Most likely, given what we know about eyeless creatures today, they were light sensitive on their bodies (as we are) so the concentration of nerves in localized areas to sense light would be a modification of existing things.

Barbarian observes:
The schizochroal eye, with relatively few, more complex lenses, was easily evolved from the holochroal eye by paedomorphosis.

'Easily evolved' indeed. Of course.

Yep. Could be a single mutation. The timing of development in eyes merely had to slow down to produce the more evolved trilobite eye.

All early trilobites (Cambrian), had holochroal eyes and it would seem hard to evolve the distinctive phacopid schizochroal eye from this form. The answer is thought to lie in ontogenetic (developmental) processes on an evolutionary time scale.

Yes, of course. Given enough billion years, anything's possible, isn't it?Like hell it is.

This is a moderated Christian board. Try to conduct yourself appropriately. All that's necessary for the evolution of the primitive trilobite eye to the more evolved eye, is retention of juvenile traits in the adult. A single mutation, changing the timing of eye development would do it.

Paedomorphosis is the retention of ancestral juvenile characteristics into adulthood in the descendent.

Paedomorphosis can occur three ways: Progenesis (early sexual maturation in an otherwise juvenile body), Neoteny (reduced rate of morphological development), and Post-displacement (delayed growth of certain structures relative to others).

If you want a good laugh, go read the wiki article on paedomorphosis. Bet you didn't know that Betty Boop is a great example of it?

Cartoonists copy paedomorphosis, because retention of juvenile traits in mammals is taken as cute. Adult mammals are attracted to such traits and are stimulated to protect animals with such traits.

The development of schizochroal eyes in phacopid trilobites is a good example of post-displacement paedomorphosis. The eyes of immature holochroal Cambrian trilobites were basically miniature schizochroal eyes.

Oh yeah. So the IMMATURE, simpler beasts had these wonderful eyes, did they?

Yep. We have fossils of immature ones. And that's what they have. The schizochroal eyes in adults were the result of paedomorphosis.

Does it ever occur to you to ask some questions round about here, B?

That's what scientists do.

Like, um, where did these immature critters get such remarkable things?

Simpler eyes:

Naraoia
Had no eyes.

Kuamaia
Had simple, ocelli-like eyes

Redlichia
Had two simple compound eyes, and apparently one ocellus.

And so on.

It sounds as if the EARLIER creatures were more highly 'evolved'.

No. See above.

In Phacopida, these were retained, via delayed growth of these immature structures (post-displacement), into the adult form.

You really should read these articles you quote with a bit more thoughtfulness, B. See the word RETAINED? Know what it means?

For example, humans retain the infantile proportions of primate hands and skull as adults. This gives us a huge advantage over other primates, since it allows a larger brain, and better manual dexterity.

But just in case it may have slipped your mind, let me remind you: it ALREADY EXISTED, and was NOT LOST.

Just as paedomorphosis meant a huge advantage for humans. Many evoluitionary advances are caused by retention of juvenile traits.

Not this time, at least. Ignorance is the enemy. Knowledge will lead you to the truth.

The evolution of mitosis and the eukaryotic condition.
J Pickett-Heaps - Bio Systems, 1974 - ncbi.nlm.nih.gov
1. Biosystems. 1974 Jul;6(1):37-48. The evolution of mitosis and the eukaryotic condition.


Turns out that one isn't that hard to see, either:

Origins of Life and Evolution of Biospheres
Volume 13, Numbers 3-4, 183-193, DOI: 10.1007/BF00927170
From proto-mitosis to mitosis — An alternative hypothesis on the origin and evolution of the mitotic spindle

U. -P. Roos


Based on the assumption that the ancestral proto-eukaryote evolved from an ameboid prokarybte I propose the hypothesis that nuclear division of the proto-eukaryote was effected by the same system of contractile filaments it used for ameboid movement and cytosis.

Excuse me, but don't I hear a loud piece of question begging here?

Don't see how.

When the nuclear membranes evolved [QB, QB, QB!!!] from the cell membrane,

Such nonsense! Doesn't this guy know, and don't you either, about such material as this:"One of the great mysteries in biology is the origin of cell membranes, the protective layers that completely surround the complex chemical soup in which many of life's most delicate processes take place."

It's a clue that the first thing absolutely required for the sort of life we know, is the simplest of all, composed of materials that can occur abiotically, and self-assembles. Had to be so. And it hasn't changed over billions of years; the cell membrane remains a simple phospholipid bilayer. Seems clear why; no conceivable mutation could replace it without destroying the cell, and apparently, no modification was possible. There are lots of molecules that are in the cell membrane, but none of them are actually part of it.

Since we have no real idea of how cell mambranes were produced/evolved,

You've been misled about that:

Trends Biochem Sci. 2004 Sep;29(9):469-77.
Ancestral lipid biosynthesis and early membrane evolution.
Peretó J, López-García P, Moreira D.
Source

Unité d'Ecologie, Systématique et Evolution, UMR CNRS 8079, Université Paris-Sud, 91405 Orsay Cedex, France.
Abstract

Archaea possess unique membrane phospholipids that generally comprise isoprenoid ethers built on sn-glycerol-1-phosphate (G1P). By contrast, bacterial and eukaryal membrane phospholipids are fatty acid esters linked to sn-glycerol-3-phosphate (G3P). The two key dehydrogenase enzymes that produce G1P and G3P, G1PDH and G3PDH, respectively, are not homologous. Various models propose that these enzymes originated during the speciation of the two prokaryotic domains, and the nature (and even the very existence) of lipid membranes in the last universal common ancestor (cenancestor) is subject to debate. G1PDH and G3PDH belong to two separate superfamilies that are universally distributed, suggesting that members of both superfamilies existed in the cenancestor. Furthermore, archaea possess homologues to known bacterial genes involved in fatty acid metabolism and synthesize fatty acid phospholipids. The cenancestor seems likely to have been endowed with membrane lipids whose synthesis was enzymatic but probably non-stereospecific.

don't you think this is another pece of rank question-begging?

Technically, it's an inference from evidence.

He has not asked fundamental questions, and you ought to be asking them too, instead of merely swallowing this guff.

It's a lot more interesting and complex than you were led to believe.

There, isn't that marvellous? Anybody can see that that is exactly how it happened! Like hell!You got any idea WHY it happened?

See above. Modification of existing things. If you want to persuasively argue for something else, you'll need to find some evidence to support your beliefs.

 

[Asyncritus]

Comment by New Scientist:

"One of evolution's most astonishing CREATIONS!!!"

HEH HEH HEH!!!

http://www.newscientist.com/article/dn9951-top-10-lifes-greatest-inventions.html

Somebody's a little confused here...

 

[Asyncritus]

Isn't this just pathetic?
http://www.newscientist.com/article/dn9951-top-10-lifes-greatest-inventions.html Emphasis and comments mine.

The first eyes appeared about 543 million years ago - the very beginning of the Cambrian period - in a group of trilobites called the Redlichia.

Their eyes were compound, similar to those of modern insects, and probably evolved from light-sensitive pits.

And their appearance in the fossil record is strikingly sudden - [Heh heh heh! Creation anybody?] trilobite ancestors from 544 million years ago don't have eyes.

So what happened in that magic million years?

Surely eyes are just too complex to appear all of a sudden? [You don't say!]

Not so, according to Dan-Eric Nilsson of Lund University in Sweden. He has calculated that it would take only half a million years [why half a million? Why not just 2 or 3 days?] for a patch of light-sensitive cells to evolve into a compound eye. [Where did you say this joker came from?]

"Eyes sparked an evolutionary arms race that transformed the planet". That's not to say the difference was trivial. [You're darned tootin' it wasnt!]

Patches of photosensitive cells were probably common long before the Cambrian, allowing early animals to detect light and sense what direction it was coming from. Such rudimentary sense organs are still used by jellyfish, flatworms and other obscure and primitive groups, and are clearly better than nothing. But they are not eyes. [Hmmmm!]

A true eye needs something extra - a lens that can focus light to form an image. "If you suddenly obtain a lens, the effectiveness goes from about 1 per cent to 100 per cent," says Andrew Parker, a zoologist at the University of Oxford. [Woweeee! No kidding! They handing out degrees at Oxford for this kind of junk?]

Trilobites weren't the only animals to stumble across this invention.

[Stumble? Shtumble? Oh yeah, Leeuwenhoek only managed to stumble on how to make a microscope. But the ol' trilobite didn't have a brain - but a pair of very big feet!] Are these people nuts or what?

Biologists believe that eyes could have evolved independently on many occasions [and perhaps pigs, giraffes and hippopotamuses may have wings too], though genetic evidence suggests one ancestor for all eyes
[Genetic evidence? What genetic evidence? Doesn't a nonsensical statement like that cast doubt on the whole of this 'genetic evidence' nonsense?]. But either way, trilobites were the first.

[Oh dear. They never learn, do they. The most complex eyes on the planet just happened to appear first. First! FIRST! Very odd thing, this evolution business. Works back to front most of the time.]

 

[Barbarian]

Somebody's a little confused here...

Indeed. From your link:

A true eye needs something extra - a lens that can focus light to form an image.

Turns out, it doesn't need a lens. Nautilids, for example, form an image on a retina, and have no lens at all.
The soft parts of Nautilus differ from those of coleoid cephalopods in numerous ways; one of the most obvious is that there is an array of tens of tentacles in place of the eight or ten arms of octopuses or squids. The eyes, although large, have no lens; rather, each has a small “pinhole” opening to allow the entry of light.
http://www.springerlink.com/content/g2770u1w089v1819/

Cutting and pasting things you know nothing about, is a continuous source of embarrassment for you, and a source of amusement for the rest of us. Just saying...

In fact, there is a continuous range of eyes from a simple light-sensitive tissue in a depression, to a fully functional nautilus eye. And there are organisms with a simple light-sensitive tissue in a cupped depression, capable of forming an image. Want to learn about it?

I would think that an organ capable of forming a optical image could be nothing but an eye, unless you want to redefine "eye" to mean only organs with lenses.

 

[Asyncritus]

Cutting and pasting things you know nothing about, is a continuous source of embarrassment for you, and a source of amusement for the rest of us. Just saying...

You're 'just saying' nonsense. Here's Parker (from wiki). Go argue with him:

Andrew Parker (born 1967) (Ph.D. Macquarie University) is a visiting member of the University of Oxford Department of Zoology since 1999. He is a Royal Society University Research Fellow, an Ernest Cook Research Fellow, and a Research Associate of the Australian Museum and University of Sydney. He was characterised by The Times as "one of the three most important young scientists in the world for his work in investigating and answering the great riddle of the Cambrian explosion."[1] Since 2003 he has lived in Oxfordshire, in the United Kingdom.

Can you match that?

In fact, there is a continuous range of eyes from a simple light-sensitive tissue in a depression, to a fully functional nautilus eye. And there are organisms with a simple light-sensitive tissue in a cupped depression, capable of forming an image. Want to learn about it?

Not really. Your continuous series requires continuous question-begging explanations as to how and why they arose.

Can you account for how the compound eye arose in the Cambrian? NO question begging, please, and do answer the question.

I would think that an organ capable of forming a optical image could be nothing but an eye, unless you want to redefine "eye" to mean only organs with lenses.

You can think what you like. You need to provide, in this instance at least, some evidence as to how the compound eye arose in the Cambrian, and why it has remained virtually unchanged till today in, for example, the dragonflies.

Have fun.