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The Visual System (was The Eye)

Administrator2

New Member
EXCREATIONIST

Consider this picture: http://www.visiontests.com/Illusions/scingrid/
The picture involves a grid with white dots and the problem is to count the
black dots. There actually aren't any black dots there, but there appear to
be.
If our visual system evolved to allow us to hunt and gather, I wouldn't
wouldn't be surprised if it didn't work properly for unnatural scenes like
this one.
But if our visual system was designed by an all-knowing creator, I thought
it would be capable of seeing things fairly accurately. It appears that
there is a bug in our visual system. And since everyone seems to have this
bug, Adam and Eve would have had it too. So did Adam and Eve have this bug
when they were created? Or did the same bug just appear in both of them when
they were cursed?
If God was all-knowing, he would have known that humans would eventually
stop living naked in the Garden of Eden, gathering food, and go out and
create things such as pictures like the one this thread is about. Or did God
design humans to be suited to a primitive lifestyle?

[ May 10, 2002, 01:14 AM: Message edited by: Administrator ]
 

Administrator2

New Member
THE GALATIAN

It turns out that our vision is not quite perfect in another way. Because
our retina is "backwards", with the nerves on the outside, and the rods and
cones behind them, we have a blind spot. Cephalopods have theirs right side
out, and don't have this defect.
If "design" was part of creation, one would have to conclude that God did a
better job on squid than on humans. This seems absurd.
 

Administrator2

New Member
HELEN
The following is from a friend of mine, Stephen Jones, in Australia. I
would also like to add before I quote it that the idea of a human
judging God where anything God has done is concerned is bizarre and
arrogant in the extreme.

Here is Steve’s email:

It is a commonplace in Darwinist anti-design polemics that the vertebrate eye is badly designed, being allegedly `wired backwards' with optic nerve ganglions getting in the way of incoming light to the retina. For example,
Dawkins writes:

"Any engineer would naturally assume that the photocells would point towards the light, with their wires leading backwards towards the brain.
He would laugh at any suggestion that the photocells might point away from the light, with their wires departing on the side nearest the light. Yet this is exactly what happens in all vertebrate retinas. Each photocell is, in effect,
wired in backwards, with its wire sticking out on the side nearest the light.
The wire has to travel over the surface of the retina, to a point where it dives through a hole in the retina (the so-called 'blind spot') to join the optic nerve. This means that the light, instead of being granted an unrestricted passage to the photocells, has to pass through a forest of connecting wires, presumably suffering at least some attenuation and distortion (actually probably not much but, still, it is the principle
of the thing that would offend any tidy-minded engineer!)." (Dawkins R., "The Blind Watchmaker," 1991, reprint, p93).

In fact leading Darwinist theoretician George C. Williams says that the vertebrate eye is "stupidly designed" ("Natural Selection: Domains, Levels, and Challenges," 1992, pp72-73), because of this inversion, and anthropologist Jared Diamond claims that "A camera designer who
committed such a blunder would be fired immediately." ("Voyage of the Overloaded Ark," Discover, June 1985, pp82-92).

This "God-wouldn't-do-it-that-way" argument has been answered satisfactorily by design theorists, for example see George Ayoub's "On the
Design of the Vertebrate Retina," Origins & Design 17:1, Winter 1996, at:

http://www.arn.org/docs/odesign/od171/retina171.htm

(click on Figure 2 for a nice diagram of these ganglions), and Paul Nelson's "Jettison the Arguments, or the Rule?: The Place of Darwinian
Theological Themata in Evolutionary Reasoning," at:

http://www.arn.org/docs/nelson/pn_jettison.htm

But here is a BBC Sci-Tech article that cites a recent Harvard study which found that those self-same ganglions are part of an early-warning system that enables the human eye to detect and "calculate the future position of a
moving object" and then to "fire off an alert message to the brain thousandths of a second before the object actually arrives in that
place":

http://news.bbc.co.uk/hi/english/sci/tech/newsid_305000/305411.stm

This enables "tennis players and cricketers..[to]... routinely react to balls travelling at up to 100mph, when technically their brains should not be able to register them before they are gone."

So it seems that this alleged `bug' is actually a feature! If this holds up, then not only has the human eye the normal visual circuitry, but it even has additional pre-processing circuitry, the like of which has only become possible in human computer technology in the mid-20th century! As
Denton points out, it is only as our technology develops that we can begin to appreciate the incredible ingenuity of the advanced technology in the living world:

"But it is not just the complexity of living systems which is so profoundly challenging, there is also the incredible ingenuity that is so often
manifest in their design. Ingenuity in biological design is particularly striking when it is manifest in solutions to problems analogous to those met in our own technology. Without the existence of the camera and the telescope, much
of the ingenuity in the design of the eye would not have been perceived.

Although the anatomical components of the eye were well known by scientists in the fifteenth century, the ingenuity of its design was not
appreciated until the seventeenth century when the basic optics of image formation were first clearly expressed by Kepler and later by Descartes.

However, it was only in the eighteenth and nineteenth centuries, as the construction of optical instruments became more complicated, utilizing a movable iris, a focusing device, and corrections for spherical and chromatic
aberration, all features which have their analogue in the eye, that the ingenuity of the optical system could at last be appreciated fully by Darwin and his contemporaries." (Denton M.J., "Evolution: A Theory in Crisis,"
1985, p332).

If the human eye indeed has additional pre-processing visual circuitry then it is even better designed than design theorists had imagined. And the Darwinist problem of explaining away the ingenious design of the eye has just become even *more* "absurd in the highest degree":

"To suppose that the eye with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of
light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest degree." (Darwin C., "The Origin of Species," 6th Edition, 1928, reprint, p167).
 

Administrator2

New Member
EXCREATIONIST

So far no-one has commented on my original post.

Here are some better examples of the scintillating grid effect: http://members.ozemail.com.au/~wenke/illusions/scint.htm http://members.ozemail.com.au/~wenke/illusions/black_dots.jpg http://members.ozemail.com.au/~wenke/illusions/white_dots.JPG

When you stare at a dot, it stays the correct colour, which shows that this
isn't just simple computer animation. You can even see the effect if you
print out these pictures but it helps to make the blacks and whites as
intense as possible - by using dark inks and looking at it in the sunlight.

The Hermann grid involves a similar effect but it is much less dramatic: http://dragon.uml.edu/psych/hg1.jpg

If you focus on white parts of the picture you see the true whiteness, but
areas that are only in your gaze can look darker.

By the way, in the "Eye Design Book"'s table of figures, http://www.eyedesignbook.com/ch1/figuresch1.html
there doesn't seem to be any optical illusion pictures so it isn't relevant
to my original post. (Though it would be relevant to the Galatian's post)
 

Administrator2

New Member
JOHN PAUL

Excreationist:
Consider this picture: http://www.visiontests.com/Illusions/scingrid/
The picture involves a grid with white dots and the problem is to count the
black dots. There actually aren't any black dots there, but there appear to
be.


John Paul:
I “saw” what appeared to be gray dots.

Excreationist:
If our visual system evolved to allow us to hunt and gather, I wouldn't be surprised if it didn't work properly for unnatural scenes like this one.


John Paul:
Evolved from what? Do all organisms with visual systems “see” black or gray dots when presented with your example? And which part of the visual system “…didn’t work properly for unnatural scenes like this one”? Is it something in the eye, something in the brain, something in-between or a collection of out-of-tolerance components?

So if I took millions of these pictures and put them on every tree in every forest, do you think it would affect hunters? I guess I don’t get your point. That picture doesn’t appear in nature, thus the unnatural label. Seeing that it doesn’t appear in nature it wouldn’t affect our ability to hunt & gather, unless we hunted & gathered in man-made fields of optical confusion.

Excreationist:
But if our visual system was designed by an all-knowing creator, I thought it would be capable of seeing things fairly accurately.


John Paul:
Just because a Creator is “all-knowing” doesn’t mean the creation has to be perfect, as we perceive perfect. Then you have to realize that the originally Created visual system has been subjected to millennia of mutations acted upon by natural selection. IOW, even if the visual system were Created perfectly doesn’t mean it had to remain so.

Excreationist:
It appears that there is a bug in our visual system.


John Paul:
Or a bug in this line of thought.

Excreationist:
And since everyone seems to have this bug, Adam and Eve would have had it too.


John Paul:
What type of logic is that? Why couldn’t the alleged bug be the result of evolution on a once very good Special Creation?

Excreationist:
So did Adam and Eve have this bug when they were created?


John Paul:
Wait, you just said they would have had it. First we have to determine if a bug actually exists. Then we have to determine what part of the visual system is causing this bug.

Excreationist:
Or did the same bug just appear in both of them when they were cursed?


John Paul:
I’ll stick with the alleged bug being due to evolutionary processes. Adam & Eve didn’t have to have this alleged bug, just the genetic algorithm acting with an evolutionary algorithm acted upon by natural selection, that produced it.

Excreationist:
If God was all-knowing, he would have known that humans would eventually stop living naked in the Garden of Eden, gathering food, and go out and create things such as pictures like the one this thread is about.


John Paul:
But God, being all knowing, knew that unnatural scenarios like you have presented do not exist in nature and would not affect our ability to hunt & gather.

Excreationist:
Or did God design humans to be suited to a primitive lifestyle?


John Paul:
God, being all knowing, knew humans would require the ability to learn. So far it has worked out although we still have much to learn. But that is what science is for.

Here’s an experiment- Take a small population of humans. Put them in a large “bio-dome” type structure. In place of natural backdrops put unnatural man-made optically confusing backdrops. Then we could see if that population’s visual system evolves to compensate and at what cost.

God Bless,

John Paul
 

Administrator2

New Member
PAUL OF EUGENE

Helen's quote from Darwin, listed above, might lead some to think Darwin felt the eye didn't, after all, evolve. In the interests of accuracy, here is a more extended quote from the same passage, which makes some headway into explaining how the eye could, in fact, come about through evolution (The rest is directly from Darwin)
To suppose that the eye with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest degree. When it was first said that the sun stood still and the world turned round, the common sense of mankind declared the doctrine false; but the old saying of Vox populi, vox Dei, as every philosopher knows, cannot be trusted in science. Reason tells me, that if numerous gradations from a simple and imperfect eye to one complex and perfect can be shown to exist, each grade being useful to its possessor, as is certainly the case; if further, the eye ever varies and the variations be inherited, as is likewise certainly the case and if such variations should be useful to any animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, should not be considered as subversive of the theory. How a nerve comes to be sensitive to light, hardly concerns us more than how life itself originated; but I may remark that, as some of the lowest organisms, in which nerves cannot be detected, are capable of perceiving light, it does not seem impossible that certain sensitive elements in their sarcode should become aggregated and developed into nerves, endowed with this special sensibility.

In searching for the gradations through which an orgain in any species has been perfected, we ought to look exclusively to its lineal progenitors; but this is scarcely ever possible, and we are forced to look to other species and genera of the same group, that is to the collateral descendants from the same parent-form, in order to see what gradations are possible, and for the chance of some gradations having been transmitted in an unaltered or little altered condition. But the state of the same organ in distinct classes may incidentally throw light on the steps by which it has been perfected.

The simplest organ which can be called an eye consists of an optic nerve, surrounded by pigment-cells, and covered by translucent skin, but without any lens or other refractive body. We may, however, according to M. Jourdain, descend even a step lower and find aggregates of pigment-cells, apparently serving as organs of vision, without any nerves, and resting merely on sarcodic tissue. Eyes of the above simple nature are not capable of distinct vision, and serve only to distinguish light from darkness. In certain star-fishes, small depressions in the layer of pigment which surrounds the nerve are filled, as described by the author just quoted, with transparent gelatinous matter, projecting with a convex surface, like the cornea in the higher animals. He suggests that this serves not to form an image, but only to concentrate the luminous rays and render their perception more easy. In this concentration of the rays we gain the first and by far the most important step towards the formation of a true, picture-forming eye; for we have only to place the naked extremity of the optic nerve, which in some of the lower animals lies deeply buried in the body, and in some near the surface, at the right distance from the concentrating apparatus, and an image will be formed on it.

In the great class of the Articulata, we may start from an optic nerve simply coated with pigment, the latter sometimes forming a sort of pupil, but destitute of a lens or other optical contrivance. With insects it is now known that the numerous facets on the cornea of their great compound eyes form true lenses, and that the cones include curiously modified nervous filaments. But these organs in the Articulata are so much diversified that Muller formerly made three main classes with seven subdivisions, besides a fourth main class of aggregated simple eyes.

When we reflect on these facts, here given much too briefly, with respect to the wide, diversified, and graduated range of structure in the eyes of the lower animals; and when we bear in mind how small the number of all living forms must be in comparison with those which have become extinct, the difficulty ceases to be very great in believing that natural selection may have converted the simple apparatus of an optic nerve, coated with pigment and invested by transparent membrane, into an optical instrument as perfect as is possessed by any member of the articulate class.

[ May 04, 2002, 12:29 AM: Message edited by: Administrator ]
 

Administrator2

New Member
EXCREATIONIST

John Paul:
I'm assuming that you are a creationist that believes that the world is
about 6000 years old.

I "saw" what appeared to be gray dots.
Actually that was a very poor example of the scintillating grid effect. In
my later post I gave links to much better examples, such as these:
http://members.ozemail.com.au/~wenke/illusions/scint.htm
http://members.ozemail.com.au/~wenke/illusions/black_dots.jpg

Anyway, even though you saw gray dots rather than black dots, there actually
weren't any gray dots there! If you stare at a single dot rather than move
your eyes around, you'll see that it is completely white. This works much
better in my later examples.

Evolved from what?
That's irrelevant. "Intelligent Design" is on trial here.

Do all organisms with visual systems "see" black or gray dots when
presented with your example?


Maybe. At the moment the only way to find out if someone sees it is to ask
them and it is hard to talk to animals. But that is irrelevant. I'm talking
about the creature that was supposedly created in God's image - humans.

And which part of the visual system ".didn't work properly for unnatural
scenes like this one"? Is it something in the eye, something in the brain,
something in-between or a collection of out-of-tolerance components?


That is irrelevant. I'm just pointing out that a problem exists. I mean it
isn't necessary to know how a car works to recognize that it isn't working
properly.

So if I took millions of these pictures and put them on every tree in
every forest, do you think it would affect hunters? I guess I don't get your
point. That picture doesn't appear in nature, thus the unnatural label.
Seeing that it doesn't appear in nature it wouldn't affect our ability to
hunt & gather, unless we hunted & gathered in man-made fields of optical
confusion.


Basically we didn't have a reason to see these kinds of pictures properly if
we evolved from primitive hunter-gatherers - but *if* we were perfectly
designed then we shouldn't have major flaws like that. In my later examples
(see earlier in this post) I showed this effect more dramatically.

Just because a Creator is "all-knowing" doesn't mean the creation has to
be perfect, as we perceive perfect.


In Genesis 1:31 it says that everything God made was "very good" (i.e.
perfect). But I agree that he could have different standards than we do -
e.g. he thinks eternal punishment for making some mistakes is perfectly
just, etc. But anyway, creationists normally go on about how things are so
perfectly designed - that infinite intelligence must have been involved. If
our inability to see that simple picture somewhat accurately is perfect
design then the word "perfect" isn't being used how I'd normally use it - I
thought "perfect" means that it is impossible to improve on it.

Then you have to realize that the originally Created visual system has
been subjected to millennia of mutations acted upon by natural selection.
IOW, even if the visual system were Created perfectly doesn't mean it had to
remain so.


But look at the other mutations people have - like short-sightedness or
obesity or acne, etc - there are always people who escape these mutations.
I've posted this these pictures on four different messageboards and no-one
has ever claimed to be able to see this picture without having major
problems. I've also looked over the internet about it and there is no
mention of anyone ever being immune to problems seeing those pictures. There
are about 3 billion pairs of bases in human DNA... let's assume that the
mutation of any one or more of 3000 particular bases results in problems
seeing that picture. Well there is still a one in a million chance of a
non-affected person giving birth to someone who has the problem. It is
extremely unlikely that this mutation would be present in all of us by
chance. And maybe someone is immune to the problem - they'd be like 1 in
1000 or 1 in 10,000. It would still be a virtually universal mutation. It is
much more likely that this 1 in a million mutation happened to all of Adam
and Eve's children than for it to happen later. If it happened later then it
this 1 in a million mutation would have to happen to every family line which
could involve thousands or millions of babies.
http://members.ozemail.com.au/~wenke/bible/genealogies.htm
This is a webpage I made which talks about the genealogies in the Bible. As
you can see, there were about ten generations before the world-wide flood.
http://www.answersingenesis.org/docs/3563.asp
According to that Answers in Genesis article, the flood happened about 4300
years ago. If we assume that the time for each generation is 20 years on
average, then we each had about 200 generations before us. There is a
0.000001 chance for a generation to get that mutation and a 0.999999 chance
not to get it. Now to be generous, let's say we were the millionth
generation after Adam and Eve. Each ancestor before us had a 99.9999% chance
of escaping the 1 in a million mutation. So that's 0.999999 to the power of
1,000,000. That is about 0.36787925723164509428579812527037 or 36.8%.
There's a 36.8% chance that for any given person in the one millionth
generation after Adam and Eve, that every single one of their ancestors
didn't get the mutation. So they didn't inherit the one in a million
mutation and they didn't develop the mutation either. Now say there were
only 200 generations after Adam and Eve. 0.999999^200 =
0.99980001989868666468241443236634 so virtually all people today wouldn't
have inherited that mutation from their ancestors - only 0.02% would have -
or 1 in 5000. (It would be a fairly rare thing)
So it seems unlikely that this was just another mutation - like
short-sightedness. Unless it is so widespread (or universal) due to chance.

"It appears that there is a bug in our visual system."
Or a bug in this line of thought.


Even you said that you saw gray dots. Well there were only white dots there.
If our eyes were designed to let us see the world accurately - with some
limitations such as the amount of detail we can see then this looks like our
visual system isn't working properly.

"And since everyone seems to have this bug, Adam and Eve would have had
it
too."
What type of logic is that? Why couldn't the alleged bug be the result of
evolution on a once very good Special Creation?


Earlier in this post I talked about the extremely low chances of this
problem being present in virtually everyone (that I know of at least). Some
might see gray dots rather than black, but that is still a problem.

"So did Adam and Eve have this bug when they were created?"
Wait, you just said they would have had it.


If Adam and Eve had it then you don't have to worry about these probability
problems. Or maybe you think that an extraordinarily improbable thing has
happened with these mutations spreading to (virtually?) everyone.

First we have to determine if a bug actually exists.

You said you saw gray dots but if you study them closely they should appear
their true colour - white. I would say that this could easily be improved
upon by us seeing white dots in the first place. So it appears less than
perfect. And you yourself think that a mutation is involved. By "bug" I mean
flaw or mutation anyway.

Then we have to determine what part of the visual system is causing this
bug.


It would either be our eyes or our brain. I don't think it makes any
difference which it is.

"Or did the same bug just appear in both of them when they were cursed?"
I'll stick with the alleged bug being due to evolutionary processes. Adam &
Eve didn't have to have this alleged bug, just the genetic algorithm acting
with an evolutionary algorithm acted upon by natural selection, that
produced it.


Well as I said earlier, it is extremely unlikely that this mutation would be
so universal today. And could you decide whether what you saw was a result
of a mutation or if it is how God intended humans to see the world? (And
therefore Adam and Eve would see that picture in the same way)

But God, being all knowing, knew that unnatural scenarios like you have
presented do not exist in nature and would not affect our ability to hunt &
gather.


In the Bible humans were originally naked gardeners, then they were farmers
and animal herders. It is in the evolutionary story that people were
originally hunter-gatherers. And then Cain built a city - God should have
forseen that humans would be civilized.

"Or did God design humans to be suited to a primitive lifestyle?"
God, being all knowing, knew humans would require the ability to learn. So
far it has worked out although we still have much to learn. But that is what
science is for.


Well in the first few chapters of Genesis, people discover things like
iron-working and build cities. So they were very innovative back then. What
my question meant was whether God would want us to see non-primitive
pictures accurately or not or if he designed us to be naked gardeners.
(Which is similar to evolution's story about ape-men)

Here's an experiment- Take a small population of humans. Put them in a
large "bio-dome" type structure. In place of natural backdrops put unnatural
man-made optically confusing backdrops. Then we could see if that
population's visual system evolves to compensate and at what cost.


Well our brains can naturally adapt to different environments - e.g. after a
month of wearing "inverting goggles" which made everything look upside-down,
a person could ride a bicycle around.
http://www.newscientist.com/lastword/answers/795body.jsp?tp=body1
It mightn't be possible to stop having problems seeing those white dots - a
change in the person's genes would be required. And there would need to be a
selecting mechanism. e.g. those that had the problem could be sterilized and
those that could see the white dots easily could be bred. The problem is to
find someone that doesn't have the problem. Maybe after hundreds of
thousands of generations there could be one person that doesn't have
problem. Then eventually you'd have a population of people that don't have
it.
 

Administrator2

New Member
PAUL OF EUGENE

Excreationist above makes the argument that having the eye susceptible to illusions is a design flaw.

This might not necessarily be the case. It could be that being immune to illusions would impose other handicaps, such as slowing down the visual processing, which would in themselves present a hazard to our lives. Leaving in place susceptibility to a few illusions, then, could be construed as a kind of optimization for our visual system.
 

Administrator2

New Member
HELEN

Excreationist, you are involving yourself in a number of fallacious
arguments here.

1. You are not discussing the eye, you are discussing the brain’s
interpretation of what we are seeing. That is very different. We can
train our brains to interpret things differently, but the eye cannot
‘help’ seeing what it sees. This is why, on an optical illusion, you
can make yourself ‘switch’ the ways you are seeing it. It has nothing
to do with the eyes at all. The eyes simply gather the light and
associated images and send them back to the brain. Whether or not the
brain has been trained by its owner to interpret one way or the other is
no business of the eye’s.

2. Therefore it has nothing to do with the intelligent design of the
eye.

3. What makes you think that a perfect, or even a very good, design is
that way because you, with your finite knowledge and understanding, have
chosen to define it that way? Conversely, how can you know if something
is NOT intelligently designed or very good with your finite knowledge
and understanding. I think you are being a bit presumptuous in making
judgments like that!

4. “Perfect” as used in the Bible does NOT mean ‘unable to improve upon
it.’ It means “complete, lacking nothing.”

5. Your figuring of generations and heritability is not taking into
account genetic bottlenecks, such as the Flood, when a mutation by one
person could have drastic effects on all generations coming from him
which, after a bottleneck, would be a significant proportion of the
ensuing population.

6. You have NO evidence that any mutation is involved in the ‘problem’
you are stating, which actually has nothing to do with the eye at all.
 

Administrator2

New Member
EXCREATIONIST

Paul of Eugene:
Well I've been experimenting with pictures like the scintillating grid and I think I'm beginning to understand how it works. I've got to do some more research about this...

Helen:
1. You are not discussing the eye, you are discussing the brain’s interpretation of what we are seeing. That is very different....

Well I originally wanted this thread to be called "Is our visual system perfectly designed?". For some reason this admins called the thread "The Eye". I agree with what you said.


...2. Therefore it has nothing to do with the intelligent design of the eye.

As I said, I didn't choose to call this topic "The Eye". I might have started talking about the eye in the wrong way in some places because the new topic title threw me off.


3. What makes you think that a perfect, or even a very good, design is that way because you, with your finite knowledge and understanding, have chosen to define it that way? Conversely, how can you know if something is NOT intelligently designed or very good with your finite knowledge and understanding. I think you are being a bit presumptuous in making judgments like that!

I said it appears to me that there is a problem with our visual system when looking at those pictures. I've studied an image processing subject and subjects about neural networks at university so I know quite a lot about image processing. (This is what would be involved here). And in my opinion, it could be improved with a bit of tweaking. I realize that some Christians might think that this isn't a flaw and could still be an example of perfect design. I thought I.D. theory would be refutable but from your last two sentences, it is impossible to refute.


4. “Perfect” as used in the Bible does NOT mean ‘unable to improve upon it.’ It means “complete, lacking nothing.”

What about the term "perfect visual system"? If it was complete and lacked nothing then it would be able to handle special inputs such as that scintillating grid picture. Or maybe "complete" means that it is complete as far as ordinary cases go.


5. Your figuring of generations and heritability is not taking into account genetic bottlenecks, such as the Flood, when a mutation by one person could have drastic effects on all generations coming from him which, after a bottleneck, would be a significant proportion of the ensuing population.

Ok, I'll do that then. So there's 8 on the ark and let's assume that the mutation has a one in a million chance. For all of them to be born with that mutation it is about a 1,000,000^8 chance = 1 in 10^48. I haven't formally studied biology but I was under the impression that mutations involve two alleles. So both of their alleles would need to be mutated otherwise there could be an allele that is ok (but recessive). So that would be a 1,000,000^2^8 chance = 1 in 10^96. They may have inherited some mutations before the flood which would reduce those odds, but creationists usually would say that there were hardly any mutations before the flood - which explains the long life-spans.


6. You have NO evidence that any mutation is involved in the ‘problem’ you are stating, which actually has nothing to do with the eye at all.

I didn't mean to say that the eye was involved - sometimes I wasn't very precise - like when people say "your eyes are fooling you!". I didn't say that I think a mutation was involved. I just offered that as an explanation that creationists might want to use. It was kind of a set-up.
 

Administrator2

New Member
HELEN

Thought this article might be of interest here, as it seems to address
the topic perhaps a little more closely regarding what the eye picks up:

=========

Imperfect optics may be the eye's defence against chromatic blur
James S. McLellan, Susana Marcos, Pedro M. Prieto, & Stephen A. Burns
Nature, 417, 174 - 176 (9 May 2002)

The optics of the eye cause different wavelengths of light to be
differentially focused at the retina. This phenomenon is due to
longitudinal chromatic aberration, a wavelength-dependent change in
refractive power. Retinal image quality may consequently vary for the
different classes of cone photoreceptors, cells tuned to absorb bands of

different wavelengths. For instance, it has been assumed that when the
eye is focused for mid-spectral wavelengths near the peak sensitivities
of
long- (L) and middle- (M) wavelength-sensitive cones, short-wavelength
(bluish) light is so blurred that it cannot contribute to and may even
impair spatial vision. These optical effects have been proposed to
explain
the function of the macular pigment, which selectively absorbs short-
wavelength light, and the sparsity of short-wavelength-sensitive (S)
cones. However, such explanations have ignored the effect of
monochromatic wave aberrations present in real eyes. Here we show
that, when these effects are taken into account, short wavelengths are
not as blurred as previously thought, that the potential image quality
for
S cones is comparable to that for L and M cones, and that macular
pigment has no significant function in improving the retinal image.

From the conclusion:
It has been widely assumed that chromatic defocus from the eye's optics
degrades the retinal image of short-wavelength light. But this
assumption has not previously been tested in a manner that takes into
account all of the eye's optical aberrations, measured at multiple
wavelengths. We have shown that there is actually little variability in
the
eye's image quality, as quantified by MTF, across the visible spectrum.
Wave aberrations cause the visual system to sacrifice resolution at a
single wavelength but allow it to gain approximate constancy in spatial
sensitivity across the spectrum. This constancy might provide an even
more effective solution to the problems of chromatic blur than could be
attained by attenuation and sparse sampling of short-wavelength light in
an eye with perfect optics.
 
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