DARWIN AND THE EYE

Slide 1:

CHARLES DARWIN AND THE EYE Courtesy Corel DISCUSSION 5 Ariel A. Roth

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NEW SLIDES TO BE INSERTED IN THIS DISCUSSION

REVISED DISCUSSION:

REVISED DISCUSSION Three problems about the distribution of eyes in the animal kingdom: 1. We find simple eyes in advanced organisms and advanced eyes in simple organisms: Ex. Poychaete eye and Amphioxus. 2. We find very different kinds of eyes in closely related organisms. Ex. Chambered nautilus and squid 3. Organisms that are evolutionarily isolated have similar eyes. Ex: Vertebrate and squid. Can use giraffe and squid.

OUTLINE 1. Introduction: The question 2. Variety of eyes: They do not fit an evolutionary pattern 3. Complexity of eyes: Special and interdependent parts 4. Evolution’s incomplete eye 5. The reversed retina: It works very well 6. Conclusions 7. Review questions:

OUTLINE 1. Introduction: The question 2. Variety of eyes: They do not fit an evolutionary pattern 3. Complexity of eyes: Special and interdependent parts 4. Evolution’s incomplete eye 5. The reversed retina: It works very well 6. Conclusions 7. Review questions

1. THE QUESTION:

1. THE QUESTION

INTRODUCTION THE PROBLEM :

INTRODUCTION THE PROBLEM When we look at more advanced structures of organisms such as the eye, the ear or the brain, we see deep problems for evolution. Evolutionists keep on suggesting that the eye could evolve all by itself as the eye gradually adapts itself to more advanced stages. The evolutionist Douglas Futuyma of the University of Michigan (and SUNYSB) in his book Evolutionary Biology (3 rd edition, p. 683), which has been the most popular textbook on evolution in the United States, writes “ The evolution of eyes is apparently not so improbable! Each of the many grades of photoreceptors [eyes], from the simplest to the most complex, serves an adaptive function .” What he is inferring is that the great variety of eyes that we find work and thus represent adaptations through an evolutionary process.

THE PROBLEM (Continued):

THE PROBLEM (Continued) On the other hand, the Bible gives a very different view of how the eye and the ear came to be. In Proverbs 20:12 we are told “ The hearing ear, and the seeing eye, the Lord hath made even both of them .” Which is true: the evolutionists’ viewpoint that eyes gradually formed by themselves, or the Bible that states that God made them? The question of how complex organs came to be is one of the more important problems for evolution. Over the past two centuries there has been a persistent intellectual conflagration between creationists and evolutionists about the origin of the eye. It makes a fascinating story. As can be seen in the next two slides, the general evolutionary argument is that since simple to complex eyes work, they must have evolutionary survival value, and if they have survival value they would evolve from each other. As we will illustrate below, in several ways, this latter assumption does not work.

Charles Darwin, in his famous book, (1859) The Origin of Species, p 168-171, states in a section titled “ORGANS OF EXTREME PERFECTION AND COMPLICATION” “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.” He then points out that throughout the animal kingdom there are all kinds of varieties of eyes, from a simple light sensitive spot on up to the eye of an eagle. He further argues that it is not unreasonable to think that “natural selection or the survival of the fittest” operating for millions of years in millions of individuals, might produce living optical instruments “superior to one of glass.” [Darwin’s reference to “one of glass” is probably to a telescope.] Other leading evolutionists follow Darwin: :

Charles Darwin, in his famous book, ( 1859) The Origin of Species , p 168-171, states in a section titled “ORGANS OF EXTREME PERFECTION AND COMPLICATION” “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.” He then points out that throughout the animal kingdom there are all kinds of varieties of eyes, from a simple light sensitive spot on up to the eye of an eagle. He further argues that it is not unreasonable to think that “natural selection or the survival of the fittest” operating for millions of years in millions of individuals, might produce living optical instruments “superior to one of glass.” [Darwin’s reference to “one of glass” is probably to a telescope.] Other leading evolutionists follow Darwin:

George Simpson, from Harvard University, in the 1967 book: The Meaning of Evolution, p 168-175. Argues, as Darwin does, that since all eyes from simple to complex are functional, they all have survival value. Richard Dawkins, Oxford University, 1986, in The Blind Watchmaker, p 77-87. Suggests that all eyes are useful and provide survival value. Douglas Futuyma, University of Michigan. 1998. Evolutionary Biology, 3rd Edition, p 682-684. Proposes that various eyes have survival value, and advanced features like the lens would evolve starting as a vitreous mass. :

George Simpson, from Harvard University, in the 1967 book: The Meaning of Evolution, p 168-175. Argues, as Darwin does, that since all eyes from simple to complex are functional, they all have survival value. Richard Dawkins, Oxford University, 1986, in The Blind Watchmaker, p 77-87. Suggests that all eyes are useful and provide survival value. Douglas Futuyma, University of Michigan. 1998. Evolutionary Biology, 3rd Edition, p 682-684. Proposes that various eyes have survival value, and advanced features like the lens would evolve starting as a vitreous mass.

2. THE VARIETY OF EYES :

2. THE VARIETY OF EYES

THE VARIETY OF EYES:

THE VARIETY OF EYES 1. Some eyes are very simple. They just tell if it is dark or if there is some light present or how bright the light might be. We call these light detecting eyes. 2. More advanced eyes detect a picture of the shape of things looked at. We call these image forming eyes. There are several kinds of image forming eyes. The four main ones are: A. Compound eye of trilobites and insects. These have many tiny tubes called ommatidia , each aimed in a slightly different direction. An image is put together by combining what each tube sees. B. Simple (camera) eye of many animals. This is found in a variety of animals such as vertebrates like you and also squids and octopuses. This eye is characterized by having a single lens that focuses the light rays on a light sensitive retina that lines a cavity. C. Pinhole eye of chambered nautilus. This eye is somewhat like the simple camera eye, but it does not have a lens. Instead it lets the light in through a tiny pin-size hole, the light from slightly different directions landing on different parts of the retina. It works like an old fashioned pinhole camera that had no lens. D. Scanning eye of the tiny crustacean (crab-like) Copilia and possibly some other animals. This eye forms an image by scanning across the region being looked at, somewhat like a television camera does.

LIGHT DETECTING EYES:

LIGHT DETECTING EYES On the next frame are three examples of simple light detecting “eyes.” They just tell if, or possibly how much, light is present. They do not make a picture. The associated pigment absorbs or reflects light. The dinoflgellate illustrated is a tiny one celled protozoan. In the two worms illustrated, the light sensitive organs (photoreceptors) are near the outer surface (skin) of the organisms (cuticle, epithelium). That surface is illustrated at the top of the diagrams. The light comes from above. In earthworms the many light sensitive organs they have tend to be concentrated near the ends of the worm.

EYES OF SNAILS:

EYES OF SNAILS Snails have a variety of kinds of eyes from a simple cup to an eye with a lens. Whether these eyes can detect direction or form any kind of an image is a debatable point. Their structure indicates that they cannot provide anything beyond the crudest kind of image. The varieties of the eyes of snails, as seen as you go from left to right in the next figure, are often presented by evolutionists as an example of how the eye can evolve from simpler to more complex. This seems to be their best example. This is limited change in the same basic kind of animal. In nature, however, various eyes can be very different in basic structure and function from each other. Because of these great differences in other animals, it is difficult to imagine how they might evolve from each other.

COMPOUND EYES:

COMPOUND EYES The compound eye is illustrated on the next slide. It forms a good image. It is found in many insects and some crab-like organisms. The eye is called “ compound ” because it is made up of a very large number of tiny tubes called ommatidia (one ommatidium), each with its own lens and each aimed in a slightly different direction than the surrounding ommatidia. By combining the input from each ommatidium, the organism puts together a picture of what is out there. A familiar example of compound eyes is the huge bulging eyes on either side of the head of a dragonfly. Those eyes may contain as many as 28,000 ommatidia.

Slide 32:

COMPOUND EYE After: Raven and Johnson 1992, BIOLOGY, p 831

SIMPLE EYE OR CAMERA EYE :

SIMPLE EYE OR CAMERA EYE The vertebrates , which include our most familiar animals such as fishes, amphibians, reptiles, birds, and mammals, have what is called a simple or camera eye. It is so designated because it has a single lens like an ordinary camera does. That single lens focuses the light rays entering the eye onto the retina that lines a large essentially empty spherical cavity, as illustrated in the next slide. Your retina has some one hundred million light sensitive cells (i.e. photoreceptors , also called rods and cones ). It has a small special area that lies opposite to the lens called the fovea . This area consists of some 30,000 light sensitive cells where your vision is especially acute. You are using your foveas to read these words. Some of the other different kinds of eyes will be discussed later, when we make further comparisons.

FOCUSING:

FOCUSING To form a sharp image the light rays coming from various views must focus ( converge ) on the retina. If the focus is behind or in front of the retina the image on the retina itself will be blurred. The next slide illustrates this. It is critical for viewing details that the lens of the eye focus the light rays right on the retina. In many vertebrates, including you, focusing is done by muscles in the eye that change the shape of the lens so the rays converge right on the surface of the retina. A complex system detects that the image is out of focus and directs the muscles that change the shape of the lens untill a sharp image is formed on the retina.

FOCUSING (Continued):

FOCUSING (Continued) . Fish use a different system for focusing than you do. As illustrated in the next slide, they have a spherical lens that under ordinary circumstances would not be able to focus on the retina. However, by using a gradational index of refraction , light focuses on the retina (red arrow). The index of refraction is the amount of bending of the light rays that takes place as light changes from one part to another. Fish have this unusual gradational index of refraction in the lens that focuses the light on the retina. Our manufactured lenses do not have this sophisticated kind of variable index of refraction. When a fish looks at a close object, it changes focus by using muscles in the eye that move its spherical lens forward. The school of fish in the following slide is from Enewetak Atoll. Note that the eyes are much larger than the little dark pupils. Of trivial interest is the odd fish just right of center that is swimming in the opposite direction from the rest of the school. Independence! Just an interesting sidelight of our fascinating world.

THE VARIETY OF EYES (Continued) :

THE VARIETY OF EYES (Continued) The CONVERGENT EVOLUTION problem. The basic structure of the eye of some invertebrates like the squid, and octopus is basically like that of vertebrates such as reptiles and us . How could random mutations trying to evolve eyes produce such similar structures in such varied animals? Evolutionists try to explain this by suggesting what they call parallel or convergent evolution . This means that these similar structures evolved independently by themselves. But this requires an unreasonable amount of fortuitous happenstance to produce the same kind of eye. Furthermore, to transfer the thousands of genes necessary to produce an advanced eye between advanced organisms is likewise unrealistic.

CONVEERGENT EVOLUTION (Continued) :

CONVEERGENT EVOLUTION (Continued) The case is especially difficult for evolutionists because according to their theory, the two groups: Deuterostomes, which include vertebrates and echinoderms (sea urchins), and Protostomes, which are most other animal phyla including squids, are assumed to have evolved apart from each other from a hypothetical common ancestor some 630 million years ago, long before we find their fossils or eyes. Yet the general anatomy of some of the eyes from the two groups is incredibly similar. How did that happen if they evolved from each other at such a primitive stage?

CONVERGENT EVOLUTION (Continued):

CONVERGENT EVOLUTION (Continued) The next slide illustrates a squid. Many squids are in the one meter (3 feet) size range, however some giant squids are among the largest animals we know of, reaching to 20 meters (60-70 feet) including their long tentacles. Squids also have the largest eyes we know of. They live in the deep ocean where there is hardly any light and they need large eyes to collect as much light as possible so as to see anything. The eye of a giant squid can be bigger than a basketball and reach 40 centimeters (16 inches) in diameter. These giant eyes can harbor one billion light sensitive cells (photoreceptors).

CONVERGENT EVOLUTION (Continued):

CONVERGENT EVOLUTION (Continued) The structure of the eye of the squid (a cephalopod) is illustrated in the next slide. Its basic arrangement is identical to that of a vertebrate eye. On a microscopic scale, the light sensitive cells of the retina in the two groups are different and, as we will discuss later, this results in a different internal arrangement for the retina. The second slide is a picture of an octopus, and the octopus (a cephalopod) has an advanced kind of eye similar to that of a squid.

CONVERGENT EVOLUTION (Continued):

CONVERGENT EVOLUTION (Continued) The next slide compares the squid eye with the vertebrate eye showing their identical general anatomy. The convergent evolution problem is significant also because the squid and related octopus and cuttlefish (not a fish, it is a little like a flat squid, it is called Sepia ) are such different animals from vertebrates. They are mollusks, grouped in the class Cephalopoda. They have no vertebral column (backbone) as vertebrates do, and they have all kinds of fleshy arms around their head region. They move mainly by directing a jet of water in diverse directions. Vertebrates belong to the phylum Chordata and include our well known fish, amphibians, reptiles (some evolutionists no longer consider reptiles a valid class), birds and mammals. They have a well- developed vertebral column. These different kinds of animals have very similar eyes. Could random evolutionary mutations produce such similar eyes in these two groups? This seems very unlikely. The similarity would seem to indicate a common Designer.

THE VARIETY OF EYES (Continued):

THE VARIETY OF EYES (Continued) THE DEGREE OF ADVANCEMENT IN EYES DOES NOT FOLLOW AN EVOLUTIONARY PATTERN There are many surprises when we compare the degree of advancement of eyes to the degree of advancement in various animals. Some simple animals have advanced eyes and some more advanced animals have simple eyes, and similar kinds of animals have very different kinds of eyes. There is a small marine worm (polychaete type), illustrated in the next slide, that has advanced eyes that focus by adjusting the volume of the distal vitreous compartment. These are image forming eyes. Furthermore, since this worm has muscles that move its eyes around in different directions, it appears that this simple worm is doing more with its eyes than just detecting light. It is looking at different things.

ADVANCEMENT IN EYES (CONTINUED):

ADVANCEMENT IN EYES (CONTINUED) On the other hand, spiders that are more advanced than worms, usually have only a few simple cup like eyes called ocelli (there might be some rare exceptions). In some cases it may be that these simple light detecting cups can be used to identify the direction of light, but these simple ocelli do not have the structure of image forming eyes. Furthermore advanced organisms like the lancets that belong to our own phylum (Cordata), which is considered the most advanced phylum, don’t have any kind of real eyes at all. An ocellus is illustrated in the next slide, and a lancet in the following.

ADVANCEMENT IN EYES (CONTINUED):

ADVANCEMENT IN EYES (CONTINUED) Earlier we referred to the similarity of the cephalopod (squid, octopus, and Sepia ) eye to the vertebrate eye. Strangely, in the squid group (Class Cephalopoda) we find the chambered nautilus that has an entirely different kind of eye. The chambered nautilus has the basic anatomy of a squid, with lots of short arms around its head region. It has the additional accoutrement of a coiled shell that is built one chamber at a time. As it builds its shell and grows, it lives in the last chamber built, which is the largest one. In the next slide, note the many arms and especially the peculiar eye of the chambered nautilus.

ADVANCEMENT IN EYES (CONTINUED):

ADVANCEMENT IN EYES (CONTINUED) The eye of the chambered nautilus is really extremely simple. It consists of a chamber (pocket) lined in its back part with a light sensitive retina and a little hole at the front. That is all. There is no cornea, lens or iris. The hole, designated as “pupil” in the next figure, is around one millimeter in diameter, hence this kind of eye is called a pinhole eye . This is an image forming eye. Because the pupil is so small, light coming into the eye from a small object will only strike a small area of the retina, and thus will be seen as a small object; and a whole picture of what is being looked at is put together in this same fashion. The chambered nautilus lives in the ocean and thus its eyes are filled with seawater.

ADVANCEMENT IN EYES (CONTINUED):

ADVANCEMENT IN EYES (CONTINUED) It seems strange that the chambered nautilus that is so similar to the squid, octopus, and cuttlefish should have such a different kind of eye. These organisms are all mollusks and are members of even the same class Cephalopoda, and evolutionists would assume that they all had one common evolutionary ancestor. If that is the case, it raises the question of why the chambered nautilus evolved a different kind of eye than its close relatives and ancestors? Instead, could these just be different kinds of created cephalopods? The next slide is a review of the usual cephalopod (squid) eye, for comparison with the chambered nautilus eye shown on the previous slide.

A PROBLEM FOR EVOLUTION We find similar animals, like the squid and chambered nautilus, with very different kinds of eyes. We find simple eyes in advanced animals, like the ocellus of spiders; and complex eyes in simple animals, like the eyes of some polychaete worms. The advancement of the complexity of the eye does not follow proposed animal evolution advancement in complexity. THE EVOLUTIONARY SOLUTION: Evolutionists recognize these incongruities. To resolve this, many propose that the eye evolved independently many times, perhaps 16, 20, 40, or even 65 times! They did not evolve from each other. This tends to greatly weaken the argument for evolution that we presented earlier, that simple to complex eyes work and have survival value and they could evolve from each other. Can evolutionists use the different kinds of eyes to support both the general evolution of the eye from simple to complex, and then propose separate evolution for different kinds of eyes when general evolution seems implausible? :

A PROBLEM FOR EVOLUTION We find similar animals, like the squid and chambered nautilus, with very different kinds of eyes. We find simple eyes in advanced animals, like the ocellus of spiders; and complex eyes in simple animals, like the eyes of some polychaete worms. The advancement of the complexity of the eye does not follow proposed animal evolution advancement in complexity . THE EVOLUTIONARY SOLUTION: Evolutionists recognize these incongruities. To resolve this, many propose that the eye evolved independently many times, perhaps 16, 20, 40, or even 65 times! They did not evolve from each other. This tends to greatly weaken the argument for evolution that we presented earlier, that simple to complex eyes work and have survival value and they could evolve from each other. Can evolutionists use the different kinds of eyes to support both the general evolution of the eye from simple to complex, and then propose separate evolution for different kinds of eyes when general evolution seems implausible?

A PROBLEM FOR EVOLUTION (Continued):

A PROBLEM FOR EVOLUTION (Continued) The classic scientific study on the proposed resolution to the great variety of eyes is: L. Salvini-Plawen (Univ. Vienna), Ernst Mayr, (Harvard). 1977. On the Evolution of Photoreceptors and Eyes. Evolutionary Biology 10:207-263. In this paper, these authors conclude that the eye evolved many times and state: “The results of our analysis completely substantiate Darwin’s claims, but also reveal numerous still unsolved problems.” Unfortunately the first part of this conclusion appears invalid. Their thesis that various kinds of eyes evolved independently mitigates Darwin’s argument that natural selection, operating over millions of years, would produce an eye “ superior to one of glass .”

CONCLUSIONS ABOUT THE VARIETY OF EYES – 1 As we look at the great variety of eyes in different kinds of animals we can summarize the problem they pose for evolution under two main headings: 1. The convergent evolution problem. The eyes of some invertebrates, like those of the squid, are very similar in basic structure to the eyes of vertebrates. Evolutionists often suggest a lot of parallel (convergent) evolution. But how could random evolutionary changes produce such complicated similarities? It would require a tremendous number of random but similar mutations to produce such similar structures. Besides that, most of these mutations would have no survival value because they are part of complex interdependent structures that can’t function until all necessary parts are present. :

CONCLUSIONS ABOUT THE VARIETY OF EYES – 1 As we look at the great variety of eyes in different kinds of animals we can summarize the problem they pose for evolution under two main headings: 1. The convergent evolution problem. The eyes of some invertebrates, like those of the squid, are very similar in basic structure to the eyes of vertebrates. Evolutionists often suggest a lot of parallel (convergent) evolution. But how could random evolutionary changes produce such complicated similarities? It would require a tremendous number of random but similar mutations to produce such similar structures. Besides that, most of these mutations would have no survival value because they are part of complex interdependent structures that can’t function until all necessary parts are present.

CONCLUSIONS ABOUT THE VARIETY OF EYES– 2 2. Evolutionists usually claim in a broad sense that complex eyes evolved from simple ones. At the same time, because simple eyes are found in complex animals and complex eyes are found in simple animals, and because evolutionary “cousins” like the squid and chambered nautilus have very different kinds of eyes, they agree that the eye does not follow an evolutionary sequence through the animal kingdom and they propose that the eye must have evolved independently many times for different kinds of eyes and animals. They still propose a few limited continuous evolutionary lines, such as for some mollusks, like snails, but not for mollusks like Cephalopods. However, can they still freely use the survival argument in a broad sense for the general evolution of the eye, but when the details don’t apply, claim the eye evolved independently many times? Can they use the survival argument only when the details are overlooked? Besides that, it needs to be kept in mind that survival by itself does not demonstrate evolution. Eyes would be expected to survive whether they evolved or were created by God! :

CONCLUSIONS ABOUT THE VARIETY OF EYES– 2 2. Evolutionists usually claim in a broad sense that complex eyes evolved from simple ones . At the same time, because simple eyes are found in complex animals and complex eyes are found in simple animals, and because evolutionary “cousins” like the squid and chambered nautilus have very different kinds of eyes, they agree that the eye does not follow an evolutionary sequence through the animal kingdom and they propose that the eye must have evolved independently many times for different kinds of eyes and animals. They still propose a few limited continuous evolutionary lines, such as for some mollusks, like snails, but not for mollusks like Cephalopods. However, can they still freely use the survival argument in a broad sense for the general evolution of the eye, but when the details don’t apply, claim the eye evolved independently many times? Can they use the survival argument only when the details are overlooked? Besides that, it needs to be kept in mind that survival by itself does not demonstrate evolution. Eyes would be expected to survive whether they evolved or were created by God!

It looks like you need to add two points about the varieties of eyes summary and that is (1) Complex eye in simple organisms, (2) very different eyes in closely related organisms. Point 2 on slide just above could fit with either of these. Could revise to follow: 1. Convergence, 2. complex eyes in simple organisms, 3 different eyes in similar animals. Then discussion 2 in above slide :

It looks like you need to add two points about the varieties of eyes summary and that is (1) Complex eye in simple organisms, (2) very different eyes in closely related organisms. Point 2 on slide just above could fit with either of these. Could revise to follow: 1. Convergence, 2. complex eyes in simple organisms, 3 different eyes in similar animals. Then discussion 2 in above slide

3. THE COMPLEXITY OF THE EYE:

3. THE COMPLEXITY OF THE EYE

COMPLEXITY:

COMPLEXITY When you look at the details of the eye, it turns out that the eye is much more complicated than first surmised. The next figure gives a few more details about our eyes that are basically the simple one lens vertebrate eye. In diagram A, note all the special parts to the right associated with the lens, iris and pupil . These parts are composed of many smaller interdependent parts that are necessary for proper function. Hence, they raise the question of how could these gradually evolving parts provide any survival value until all the necessary ones were present so the system could work. There are three main coats to the wall of the eye: The tough outer whitish sclera ; the middle choroid , that is rich in blood vessels; and the complicated inner retina that is nearly transparent. We will discuss these later when considering the inverted retina. The retina harbors many nerve cells and also the light-detecting cells (photoreceptors) known as the rods and cones . The rods function in detecting dim light while the cones detect bright and colored light.

DETECTION OF LIGHT:

DETECTION OF LIGHT One rod may contain 40,000,000 protein molecules called rhodopsin . When light strikes a rhodopsin molecule it bends it. That response is passed on to many more of several different kinds of molecules in an avalanche type of chemical reaction that increases the negative charge of the outside of the rod or cone. The change in electrical charge sends an impulse to other nerve cells. In the rod or cone the whole process is reversed in preparation to receive more light. At least a dozen different protein molecules are involved. Strangely, the eye of the scallop ( Pecten ) has a double retina, and the distal retina cells become electrically more negative, as is the case for man, when stimulated; while in the deeper retina the cells become more positive. This all adds to the picture we see of a strange great variety of kinds of eyes in animals.

THE TRILOBITE EYE:

THE TRILOBITE EYE You may recall that earlier we mentioned Charles Darwin’s concern about complicated eyes, including their ability to correct for spherical aberration . In spherical aberration you do not get a sharp image because parallel light rays coming into the eye do not converge on the same plane. See the two red arrows in the next slide. The even curvature of an ordinary lens is such that light coming in around the outside of the lens focuses on a different plane than light coming through the center, so the image is blurred. There are several ways to correct for spherical aberration. Trilobites do it by using a different shape of lens.

THE TRILOBITE EYE (Continued):

THE TRILOBITE EYE (Continued) The trilobite eye is of special interest because it appears to be the first image forming eye we find in the fossil record as we go up through the geologic layers. We find it in the Cambrian which is at the bottom of the fossil- rich Phanerozoic part of the geologic column. The next slide is a photograph of Mount Stevens in the Canadian Rockies. The darker layers on the hillside are deep Cambrian rocks that have been obviously pushed up. They contain an abundance of trilobites. The slide following the next slide is a sample of one of these trilobites. The arrow points to the eye region. Note the Canadian coin for scale.

THE TRILOBITE EYE (Continued):

THE TRILOBITE EYE (Continued) The trilobite eye, like the eye of an insect, is a compound eye. It has many ommatidia (tubes) each pointing in a slightly different direction, and each ommatidium has its own lens so as to give a precise image of what lies in the direction it is pointing. A general diagram of the compound eye used earlier is provided in the next slide for review.

Slide 75:

COMPOUND EYE After: Raven and Johnson 1992, BIOLOGY, p 831

THE TRILOBITE EYE (Continued):

THE TRILOBITE EYE (Continued) In order to get around the problem of spherical aberration, researchers in Europe, such as Descartes and Huygens, working several centuries ago, had invented lenses that corrected for spherical aberration. An example is provided in the next slide. Note that the incoming light rays all converge on the same plane. Amazingly, when the eyes of some trilobites were closely examined it was discovered that their lenses were of the same type as those invented by Descartes. These lenses corrected for spherical aberration and thus provided the trilobite with a sharp image of what it was looking at.

THE TRILOBITE EYE (Continued):

THE TRILOBITE EYE (Continued) This sophisticated feat of optical function found in trilobite lenses poses problems for evolution because we don’t find in the fossil record the evolutionary ancestors of these advanced eyes. As evolution would be expected to proceed by random mutations trying one kind of lens shape after another, the number of ineffective shapes tried would be enormous. Yet none have been found. Furthermore, the lenses of trilobites are made of crystals of the mineral calcite (calcium carbonate, CaCO 3 ). Calcite is a complicated mineral that bends the light rays entering or leaving it (index of refraction) at different angles (degree of bending) depending on the orientation of the crystal. In trilobite eyes the calcite of the lenses is oriented in just the proper direction so as to give the right focus. Thus one can wonder about how many random tries it would take before the trilobite would have learned how to orient calcite minerals in the right direction. And we haven't found the fossils expected for this extended evolutionary process. In several ways the trilobite eye strongly favors the creation concept.

A COMMON GENE FOR THE EYE:

A COMMON GENE FOR THE EYE Evolutionist have perceived some evidence for their theory of eye development from the genetic makeup of various organisms. It has been found that there is one of those master genes (i.e. Pax 6 , a homeobox gene found in many animals) that is associated with the development of the eye in different animals. Some complicated genetic engineering experiments conducted in Switzerland have succeeded in taking this eye-inducing gene from a mouse, which has a simple eye, and putting it in the DNA of a fruit fly, that has a compound eye, and that gene caused the development of an extra compound eye on the leg of the fly. An illustration of this extra eye is shown on the next slide. Each of the many bumps on the surface of the white eye is the end of an ommatidium of this compound eye. The ommatidia of this extra eye responded to light by generating a nerve impulse when stimulated by light. So the ommatidia were functional.

A COMMON GENE FOR THE EYE (Continued):

A COMMON GENE FOR THE EYE (Continued) Evolutionists consider the action of this master gene that causes eye development in different kinds of animals to be strong evidence of a common evolutionary origin . But this need be the case only if you assume evolution. On the creation side, it could also mean that one Designer had planned the same kind of basic developmental process in various animals. Why not use the same system of master genes that work in different animals, instead of inventing a different system for each kind of animal? This would seem like the efficient thing to do. Evolutionists also need to keep in mind that several thousand genes are involved in the development of the eye of the fly that is very different from that of a mouse eye , and evolution needs to account for all these new genes . So one similar master gene does not at all solve the problem of the great variety of eyes that we find.

THE COMPLEXITY OF THE EYE (Continued) THE SCANNING EYE OF COPILIA:

THE COMPLEXITY OF THE EYE (Continued) THE SCANNING EYE OF COPILIA One tiny animal has an unbelievably intriguing eye system. It is found in a crablike copepod called Copilia. The animal lives in the Mediterranean Sea and is only about one millimeter wide, yet it uses a scanning system that goes back and forth to form an image, somewhat like a television camera does. The system is illustrated in the next slide. The animal uses four lenses, two in front for viewing and two behind to scan the image captured by the viewing lenses. Muscles cause the scanning lenses to swing back and forth about once per second as it views the image seen by the viewing lenses.

THE SCANNING EYE OF COPILIA (Continued):

THE SCANNING EYE OF COPILIA (Continued) Such an eye provides another example of the great variety of different basic kinds of eyes we find. It does not seem possible that these very different visual systems would evolve from each other. This eye also well illustrates the difficulty of evolving complex systems. For instance in evolving this kind of eye, what use would the muscle that vibrates the scanning lens have without the evolution of the scanning lens, and of what use would the scanning lens be without a special complicated system in the brain to interpret the scans? Here, as usual, there seem to be way too many interdependent parts that are necessary to provide evolutionary survival value until all are present. Random mutations would not be expected to suddenly provide all the parts of complex working systems so that there could be some survival value.

CONCLUSIONS AND REVIEW ABOUT THE COMPLEXITY OF THE EYE 1. The very complex eyes of trilobites with sophisticated optics appear very early (Cambrian) in the fossil record of animals. How could such complexity gradually evolve without leaving any fossil record? 2. The major problem about the evolution of the eye is ignored. Complex systems with interdependent parts like the the visual system of Copilia, have no evolutionary survival value until all essential parts are present so as to be able to provide any survival value. Until then, excess useless non- functioning parts are only cumbersome impediments. This is the irreducible complexity problem. :

CONCLUSIONS AND REVIEW ABOUT THE COMPLEXITY OF THE EYE 1. The very complex eyes of trilobites with sophisticated optics appear very early (Cambrian) in the fossil record of animals. How could such complexity gradually evolve without leaving any fossil record? 2. The major problem about the evolution of the eye is ignored. Complex systems with interdependent parts like the the visual system of Copilia, have no evolutionary survival value until all essential parts are present so as to be able to provide any survival value. Until then, excess useless non- functioning parts are only cumbersome impediments. This is the irreducible complexity problem .

CONCLUSIONS AND REVIEW ABOUT THE COMPLEXITY OF THE EYE (Continued) :

CONCLUSIONS AND REVIEW ABOUT THE COMPLEXITY OF THE EYE (Continued) OTHER EXAMPLES OF INTERDEPENDENT PARTS: (a) For instance, the mechanism that adjusts the focus of the lens is useless without special muscles that change the shape of the lens and a mechanism that determines that the eye is out of focus. (b) The mechanism that adjusts the size of the pupil is useless without a mechanism that detects how much light is present. (c) An eye is useless without a part of a brain to interpret what is seen. (d) Many specialized protein molecules are dependent on each other in order to produce the complex light detection system. On the next slide is the picture of an eye. While it looks quite simple, behind what you see are intricate systems, like automatic focusing and automatic exposure features. Like a camera with the same features, it has many parts that will not work unless other parts are also present. These interdependent parts challenge any gradual evolutionary process where only one part is added at a time. There is no survival value to parts that don’t work.

Slide 87:

Courtesy Corel Professional Library

CONCLUSIONS AND REVIEW ABOUT THE COMPLEXITY OF THE EYE (Continued) Charles Darwin, in 1859, in his famous book, The Origin of Species, (p 219, Penguin Edition, 1968) obviously did not consider the problem of interdependent parts. He states: “If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down. But I can find out no such case.” Darwin tries to protect his view by using the “just prove it is impossible” type of argument when he says “not possibly.” But his “numerous, successive, slight modifications” that would not have any survival value until something worked, indicates that, in his own words, his theory has “absolutely” broken down many times.:

CONCLUSIONS AND REVIEW ABOUT THE COMPLEXITY OF THE EYE (Continued) Charles Darwin, in 1859, in his famous book, The Origin of Species , (p 219, Penguin Edition, 1968) obviously did not consider the problem of interdependent parts. He states: “If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications , my theory would absolutely break down. But I can find out no such case.” Darwin tries to protect his view by using the “just prove it is impossible” type of argument when he says “not possibly.” But his “numerous, successive, slight modifications” that would not have any survival value until something worked, indicates that, in his own words, his theory has “absolutely” broken down many times.

4. EVOLUTION’S INCOMPLETE EYE:

4. EVOLUTION’S INCOMPLETE EYE

EVOLUTION’S INCOMPLETE EYE Some evolutionists in Sweden have tried to suggest that the eye could evolve very fast. The reference for their study is: Dan-E Nilsson, Susanne Pelger (Lund University) 1994. A Pessimistic Estimate of the time required for an eye to evolve. Proceedings Royal Society of London, B 256:53-58. These authors conclude that the eye could have evolved in just 1829 steps of arbitrary 1% improvements. Furthermore, they suggest that it would take less than 364,000 years for a camera eye to evolve from a light sensitive patch. They conclude that there is enough geologic time since the Cambrian for “eyes to evolve more than 1500 times.” The main steps in their proposed model are illustrated in the next picture. :

EVOLUTION’S INCOMPLETE EYE Some evolutionists in Sweden have tried to suggest that the eye could evolve very fast. The reference for their study is: Dan-E Nilsson, Susanne Pelger ( Lund University) 1994. A Pessimistic Estimate of the time required for an eye to evolve. Proceedings Royal Society of London, B 256:53-58. These authors conclude that the eye could have evolved in just 1829 steps of arbitrary 1% improvements. Furthermore, they suggest that it would take less than 364,000 years for a camera eye to evolve from a light sensitive patch. They conclude that there is enough geologic time since the Cambrian for “eyes to evolve more than 1500 times.” The main steps in their proposed model are illustrated in the next picture.

EVOLUTION’S INCOMPLETE EYE (Continued) Their proposed model cannot be taken seriously because many important parts of the eye are not considered. Their approach is what is sometimes called “fact-free science.” Their model does serve to illustrate the great weakness of some evolutionary arguments. MISSING PARTS: 1. Retina (the most important and most complex part of the eye) 2. Brain parts to interpret what the eye sees 3. Nerve connection between eye and brain 4. Lens focusing mechanism 5. Pupil size adjusting mechanism 6. A functional lens (they make a vague suggestion) 7. New embryological process needed for vertebrates where the eye originates from the brain, not the skin as they propose 8. Muscles that move the eye:

EVOLUTION’S INCOMPLETE EYE (Continued) Their proposed model cannot be taken seriously because many important parts of the eye are not considered. Their approach is what is sometimes called “ fact-free science .” Their model does serve to illustrate the great weakness of some evolutionary arguments. MISSING PARTS: 1. Retina (the most important and most complex part of the eye) 2. Brain parts to interpret what the eye sees 3. Nerve connection between eye and brain 4. Lens focusing mechanism 5. Pupil size adjusting mechanism 6. A functional lens (they make a vague suggestion) 7. New embryological process needed for vertebrates where the eye originates from the brain, not the skin as they propose 8. Muscles that move the eye

EVOLUTION’S INCOMPLETE EYE (Continued) Despite these major omissions, some evolutionists were excited about the model. Some of their endorsing comments follow: Richard Dawkins, Oxford University. 1994. The Eye in a Twinkling. Nature 368:690-691. Results were “swift and decisive” and the time required for the evolution of the “eye is a geological blink.” Daniel Osorio, Sussex University. 1994. Eye evolution: Darwin’s Shudder Stilled. Trends in Ecology & Evolution 9:241-242. The eye has been such a problem for evolution that it is sometimes referred to as “Darwin’s shudder” INTERNET: “The eye has turned out to be the BEST PROOF of evolution.” (This overstatement has since been removed from its web page!) To a significant degree these comments, that are all highly inaccurate, likely reflect over-reactions by evolutionists to the problem the eye has posed for them for two centuries. :

EVOLUTION’S INCOMPLETE EYE (Continued) Despite these major omissions, some evolutionists were excited about the model. Some of their endorsing comments follow: Richard Dawkins, Oxford University. 1994. The Eye in a Twinkling . Nature 368:690-691. Results were “swift and decisive” and the time required for the evolution of the “eye is a geological blink.” Daniel Osorio, Sussex University. 1994. Eye evolution: Darwin’s Shudder Stilled. Trends in Ecology & Evolution 9:241-242. The eye has been such a problem for evolution that it is sometimes referred to as “Darwin’s shudder” INTERNET: “The eye has turned out to be the BEST PROOF of evolution.” (This overstatement has since been removed from its web page!) To a significant degree these comments, that are all highly inaccurate, likely reflect over-reactions by evolutionists to the problem the eye has posed for them for two centuries.

5. THE INVERTED RETINA:

5. THE INVERTED RETINA

THE INVERTED RETINA:

THE INVERTED RETINA Evolutionists claim that the eye is badly designed! They claim that the retina of vertebrates (fish, amphibians, reptiles, birds and mammals) is inverted from the way it should be. In most other animals they consider it to be verted or properly arranged. The claim of inversion is based on the fact that in vertebrates the light sensitive part ( discs ) of the photoreceptors (rods and cones) is turned away from the light instead of towards it. The next slide illustrates the two kinds of arrangements. Note the direction the light travels, and note the location of the light sensitive area of the photoreceptors. The upper figure is the verted arrangement as found in squids, spiders and many snails, etc. The lower figure is the inverted arrangement as found in vertebrates like you. Here, not only does the light have to first go through part of the rod and cone cells to reach the light sensitive discs, it has to also go through layers of neurons; and many evolutionists consider this to be a very bad design.

THE INVERTED RETINA (Continued):

THE INVERTED RETINA (Continued) In the next slide, you have examples of eyes with these two kinds of retinas. The left is that of a squid that is verted, and the right is that of a vertebrate that is inverted. At this scale, you can barely notice the difference in the thin retinas. The two kinds of retinas are quite different in microscopic details. The cephalopod retina has numerous elongated villi that contain the light sensitive molecules, while in vertebrates the pigment is stored in discs that are constantly being replaced. In the slide after the next one, there are some details of the inverted vertebrate retina. Note especially parts C and D. Light comes in from the right.

THE INVERTED RETINA (Continued) Note the derogatory comments here and on the next slide from some leading evolutionists about the inverted retina: George Williams. NY University, Stony Brook “There would be no blind spot if the vertebrate eye were really intelligently designed.” Jared Diamond. University of California at Los Angels “However the vessels and nerves aren’t located behind the photoreceptors, where any sensible engineer would have placed them, but out in front of them, where they screen some of the incoming light. A camera designer who committed such a blunder would be fired immediately. … By contrast, the eyes of the lowly squid, with the nerves artfully hidden behind the photoreceptors are an example of design perfection. If the Creator had indeed lavished his best design on the creature he shaped in his own image, creationists would surely have to conclude that God is really a squid.” :

THE INVERTED RETINA (Continued) Note the derogatory comments here and on the next slide from some leading evolutionists about the inverted retina: George Williams. NY University, Stony Brook “There would be no blind spot if the vertebrate eye were really intelligently designed.” Jared Diamond. University of California at Los Angels “However the vessels and nerves aren’t located behind the photoreceptors, where any sensible engineer would have placed them, but out in front of them, where they screen some of the incoming light. A camera designer who committed such a blunder would be fired immediately. … By contrast, the eyes of the lowly squid, with the nerves artfully hidden behind the photoreceptors are an example of design perfection. If the Creator had indeed lavished his best design on the creature he shaped in his own image, creationists would surely have to conclude that God is really a squid.”

COMMENTS FROM EVOLUTIONISTS (CONTINUED) Douglas Futuyma. University of Michigan and NYUSB “The human eye has a ‘blind spot,’…. It is caused by the functionally nonsensical arrangement of the axons of the retinal cells which run forward into the eye.” William Thwaites. San Diego State University “Vertebrates are cursed with an inside-out retina in the eye…. Did God at the time of the ‘Fall’ turn the vertebrate retina inside-out…?” Richard Dawkins. Oxford University “Any engineer…. would laugh at any suggestion that the photocells might point away from the light, with their wires departing on the side nearest to the light,…. Each photocell is, in effect, wired backwards.” :

COMMENTS FROM EVOLUTIONISTS (CONTINUED) Douglas Futuyma. University of Michigan and NYUSB “The human eye has a ‘blind spot,’…. It is caused by the functionally nonsensical arrangement of the axons of the retinal cells which run forward into the eye.” William Thwaites. San Diego State University “Vertebrates are cursed with an inside-out retina in the eye…. Did God at the time of the ‘Fall’ turn the vertebrate retina inside-out…?” Richard Dawkins. Oxford University “Any engineer…. would laugh at any suggestion that the photocells might point away from the light, with their wires departing on the side nearest to the light,…. Each photocell is, in effect, wired backwards.”

COMMENTS FROM EVOLUTIONISTS (CONTINUED) The conclusion is that the eye is so badly designed, that no intelligent designer would commit such a blunder. The implication is that there is no God. THE ALLEGED PROBLEMS OF THE REVERSED OR INVERTED RETINA ARE: 1. The light sensitive ends (discs) of the rods and cones are located (headed) away from the light. 2. The nerve processing cells in the retina are between the incoming light and the rods and cones. 3. This necessitates a blind spot where the nerve fibers leave the eye (optic disc, optic nerve). You can note all these assumed problems on the image of the vertebrate eye in the next slide.:

COMMENTS FROM EVOLUTIONISTS (CONTINUED) The conclusion is that the eye is so badly designed, that no intelligent designer would commit such a blunder. The implication is that there is no God. THE ALLEGED PROBLEMS OF THE REVERSED OR INVERTED RETINA ARE: 1. The light sensitive ends (discs) of the rods and cones are located (headed) away from the light. 2. The nerve processing cells in the retina are between the incoming light and the rods and cones. 3. This necessitates a blind spot where the nerve fibers leave the eye (optic disc, optic nerve). You can note all these assumed problems on the image of the vertebrate eye in the next slide.

THE MAIN CRITICISMS ABOUT THE INVERTED RETINA ARE NOT VALID:

THE MAIN CRITICISMS ABOUT THE INVERTED RETINA ARE NOT VALID 1. The blind spot is to the side and in our eyes we have a hard time finding it. Besides that one eye compensates for the blind spot in the other. 2. The area of acute vision (fovea) does not have thick layers of neurons between it and the incoming light that is found in other areas; hence, acute vision is hardly affected. See part B in the previous slide. 3. There appear to be very good reasons why the disc ends of the rods and cones are turned toward the back of the eye. The discs are constantly being replaced , probably to provide a fresh supply of molecules for the all important light detecting function of the eye. Each rod or cone replaces 80-90 new discs each day out of a total of some 1000 per rod or cone. Only a few discs are illustrated in part D of the previous slide. There the new discs are produced in the region labeled “Connecting stalk”; they travel towards the left and the old ones are extruded at the far end (left end) towards the back (outside) of the eye. (a) The old discs need to be removed , and this is done by the pigment epithelium. (b) The active rods and cones need to be near the choroid blood supply of the wall of the eye that provides nutrients for making new discs.

CRITICISMS NOT VALID (Continued):

CRITICISMS NOT VALID (Continued) 4. M üller cells transmit light directly through the retina. Recently ( 2007, Franze K et al. Procedings of the National Academy of Sciences 104:8287-8292 ) it has been discovered that special cells called M üller cells , that span through the retina, have a refractive index that is higher than that of the surrounding tissue and thus serve as conduits to transmit light directly through the layer of nerve cells of the retina that lie between the incoming light and the rods and cones. As illustrated in the next slide, the blue light coming in from the right is transmitted to the rods and cones by the elongated Müller cells in the retina. Hence, all the terrible problems that the inverted retina is supposed to cause, do not appear to be significant.

REVERSING THE INVERTED RETINA:

REVERSING THE INVERTED RETINA Should we reverse the retina as some evolutionists suggest that God should have done, it seems likely that we would have a visual disaster. The discs of the rods and cones would face into the light, but what would perform the essential function of the pigment epithelium in absorbing the old discs? Rods and cones are constantly at work and produce some ten billion discs per day in each of our eyes. These would accumulate in the transparent vitreous humor of the eye (see part A in the figure of the details of the vertebrate eye, four slides back), and their great numbers would soon impair our ability to see. Also, the rods and cones would be without the necessary pigment epithelium and blood supply of the choroid layer needed to absorb and replace the discs, so the disc replacing system would not work well or not at all.

REVERSING THE INVERTED RETINA (Continued):

REVERSING THE INVERTED RETINA (Continued) If under this reversal of the inverted retina we should then try to provide the disc ends of the rods and cones, pointed toward the light, as evolutionists suggest they should be, with their necessary pigment epithelium and choroid blood supply layer, these layers would have to lie on the inside of the layer of rods and cones. In other words, they would lie closer to the middle of the eye and the source of light than the rest of the retina. As a result the light coming into the eye would first have to try and get through the blood supplying choroid layer and pigment epithelium before reaching the light sensitive discs. A blood hemorrhage in the retina is extremely debilitating and illustrates how disruptive blood can be to the visual process. The pigment in the pigment epithelium that absorbs light would also be in the way and would contribute further to complete blindness. Like trying to play tennis with ripe tomatoes instead of tennis balls, this is not a great idea! The next slide illustrates this.

Slide 109:

REVERSING THE “INVERTED” RETINA NORMAL REVERSED REVERSED RETINA EYE RETINA AND CHOROID Disc Light Light sensitive retina Blood supplying choroid Fibrous sclera Light goes through transparent nerve cells. It works very well. There are fewer nerve cells in central fovea. Discs pointed towards light, but what would absorb the billions produced each day. They would eventually fill the eye. If pigment epithelium and choroid were placed on the inside to absorb discs, light could not get through to the light sensitive discs. Rod cell Some evolutionists suggest that the eye was not designed, because the light sensitive disc ends of the rods and cones point away from the light. The retina is said to be “inverted.” However if these light sensitive cells were reversed towards the light it appears that we would have a visual disaster.

CONCLUSIONS ABOUT THE INVERTED RETINA 1. While leading evolutionist propose that the inverted retina is a terrible design a few evolutionist think it is a good design. 2. The blind spot is way to the side and barely noticeable. One eye compensates for the other. 3. In the area of acute vision (fovea), the nerve cells are small and radiate away from the region, resulting in a thin nerve cell layer. Rare small blood vessels in the retina avoid this area. 4. Except for the pigment epithelium, the retina is a very transparent organ allowing light to reach the rods and cones. Also Müller cells transmit light directly through the retina. 5. The inverted retina seems necessary to provide the attention that the very active rods and cones require from the choroid’s blood supply. Reversal would be disastrous to the ability to see. 6. If, as some evolutionists claim, the eye is so badly designed, and if as some other evolutionists claim, the eye can evolve “in a twinkling”; why didn’t natural selection produce a better eye for vertebrates a long time ago! 7. The inverted retina works very well. If it didn’t you would not be able to read all this. It is hard to argue against success.:

CONCLUSIONS ABOUT THE INVERTED RETINA 1. While leading evolutionist propose that the inverted retina is a terrible design a few evolutionist think it is a good design. 2. The blind spot is way to the side and barely noticeable. One eye compensates for the other. 3. In the area of acute vision (fovea), the nerve cells are small and radiate away from the region, resulting in a thin nerve cell layer. Rare small blood vessels in the retina avoid this area. 4. Except for the pigment epithelium, the retina is a very transparent organ allowing light to reach the rods and cones. Also M ü ller cells transmit light directly through the retina. 5. The inverted retina seems necessary to provide the attention that the very active rods and cones require from the choroid’s blood supply. Reversal would be disastrous to the ability to see. 6. If, as some evolutionists claim, the eye is so badly designed, and if as some other evolutionists claim, the eye can evolve “in a twinkling”; why didn’t natural selection produce a better eye for vertebrates a long time ago! 7. The inverted retina works very well. If it didn’t you would not be able to read all this. It is hard to argue against success.

CONCLUSIONS ABOUT THE INVERTED RETINA (Continued) 8. Inversion does not follow an evolutionary pattern. Vertebrates have an inverted retina, while in general invertebrates have a verted retina. But several invertebrates have an inverted retina. Examples include a snail, a cockle (bivalve mollusk), and several spiders and scorpions. It would be a complicated process to change from one type to another, involving reorientation of light sensitive cells and nerve fibers, and then reconnection. Sudden change of several parts is implausible, and gradual change, while parts are not functional, would not be favored by survival of the fittest. Design of the various kinds of eyes seems a more plausible origin.:

CONCLUSIONS ABOUT THE INVERTED RETINA (Continued) 8. Inversion does not follow an evolutionary pattern. Vertebrates have an inverted retina, while in general invertebrates have a verted retina. But several invertebrates have an inverted retina. Examples include a snail, a cockle (bivalve mollusk), and several spiders and scorpions. It would be a complicated process to change from one type to another, involving reorientation of light sensitive cells and nerve fibers, and then reconnection. Sudden change of several parts is implausible, and gradual change, while parts are not functional, would not be favored by survival of the fittest. Design of the various kinds of eyes seems a more plausible origin.

6. SUMMARY AND CONCLUSIONS ABOUT THE EYE:

6. SUMMARY AND CONCLUSIONS ABOUT THE EYE

DARWIN AND THE EYE: SUMMARY AND CONCLUSIONS 1. Advanced eyes appear at the beginning of the animal fossil record. 2. Evolution has to invoke a lot of fortuitous parallel (convergent) random mutations to explain similar eyes in very different kinds of animals. 3. The variety and pattern of eye distribution in the animal kingdom confounds a general evolutionary scenario for the eye progressing from simple to complex. The increase in complexity of the various eyes does not fit the pattern for the advancing evolution of animals. Hence, many evolutionists suggest that when a new kind of eye appears it represents a new evolutionary process. Yet evolutionists still suggest eyes evolved from simple to complex. Can they have their explanations going both ways? 4. The problem of the evolution of complex systems in the eye, with interdependent parts that have no evolutionary survival value until all necessary parts are there so they can function, is not seriously considered by evolutionists. 5. The Nilsson-Pelger model for eye evolution is extremely incomplete. 6. The inverted retina appears to be a very good design for the needs of the vertebrate eye. :

DARWIN AND THE EYE: SUMMARY AND CONCLUSIONS 1. Advanced eyes appear at the beginning of the animal fossil record . 2. Evolution has to invoke a lot of fortuitous parallel ( convergent ) random mutations to explain similar eyes in very different kinds of animals. 3. The variety and pattern of eye distribution in the animal kingdom confounds a general evolutionary scenario for the eye progressing from simple to complex. The increase in complexity of the various eyes does not fit the pattern for the advancing evolution of animals . Hence, many evolutionists suggest that when a new kind of eye appears it represents a new evolutionary process. Yet evolutionists still suggest eyes evolved from simple to complex. Can they have their explanations going both ways? 4. The problem of the evolution of complex systems in the eye , with interdependent parts that have no evolutionary survival value until all necessary parts are there so they can function, is not seriously considered by evolutionists. 5. The Nilsson-Pelger model for eye evolution is extremely incomplete. 6. The inverted retina appears to be a very good design for the needs of the vertebrate eye.

Slide 114:

THE EYE WAS DESIGNED BY GOD Courtesy Corel Professional Library

REVIEW QUESTIONS – 1 (Answers given later below):

REVIEW QUESTIONS – 1 (Answers given later below) 1. What are the implications for creation and for evolution of the fact that the general anatomy of vertebrate and squid eyes are essentially identical. 2. Evolutionist claim that simple eyes could gradually evolve into advanced ones because all these eyes have survival value. At the same time, because very different kinds of eyes are found in animals assumed to be evolutionarily closely related and because advance eyes are found in simple animals and vice versa, they assume that eyes evolved many times independently. What are the implications of these different lines of reasoning.

REVIEW QUESTIONS – 2 (Answers given later below):

REVIEW QUESTIONS – 2 (Answers given later below) 3. When you examine the fossil record you find trilobite eyes that have sophisticated aplanatic lenses that correct for spherical aberration. What is the significance of the fact that these trilobite eyes are among the very lowest eyes found as we examine the fossil record. 4. The optical system of the copepod Copilia consists of several lenses; the focusing system of the vertebrate eye consists of a number of parts; the same is the case for the system that controls the amount of light that enters the eye. What problem do these complex systems pose for a suggested evolutionary origin?

REVIEW QUESTIONS – 3 (Answers given later below):

REVIEW QUESTIONS – 3 (Answers given later below) 5. Some evolutionists (i.e. Nilsson and Pelger, 1994) have proposed a model of how the eye could evolve very fast. In fact they suggest that the eye could have evolved 1500 times since the Cambrian. They propose 1% arbitrary steps in improvement, especially changes in the shape of the eye. What is the main problem with their model? Give details. 6. A number of leading evolutionists point out that the retina of the vertebrate eye is very badly designed because the light sensitive parts of the rods and cones are directed away from the incoming light. What appears to be the purpose of the inverted retina? What would happen if it weren’t inverted?

REVIEW QUESTIONS AND ANSWERS - 1:

REVIEW QUESTIONS AND ANSWERS - 1 1. What are the implications for creation and for evolution of the fact that the general anatomy of vertebrate and squid eyes are essentially identical. The similarity of these eyes in such different kinds of animals suggest that the same creator designed both of these eyes. Squids and vertebrates are very different kinds of animals that evolutionists assume evolved from a common ancestor long before we can find any of their kinds of fossils. It seems essentially impossible that that random mutations over millions of years could end up producing such similar eyes. Eyes don’t have to be similar, we find many very different kinds of eyes in all kinds of animals.

REVIEW QUESTIONS AND ANSWERS - 2:

REVIEW QUESTIONS AND ANSWERS - 2 2. Evolutionist claim that simple eyes could gradually evolve into advanced ones because all these eyes have survival value. At the same time, because very different kinds of eyes are found in animals assumed to be evolutionarily closely related and because advance eyes are found in simple animals and vice versa, they assume that eyes evolved many times independently. What are the implications of these different lines of reasoning. This is an example of the great breadth of evolutionary explanations used to explain different kinds of data. Evolutionists should be more cautious in using the increasing degree of complexity of various eyes to explain eye evolution when convenient and when it does not fit the data assume eyes evolved independently. At times evolution has several suggested conflicting explanations and it becomes difficult to determine which one is suppose to be the correct one.

REVIEW QUESTIONS AND ANSWERS - 3:

REVIEW QUESTIONS AND ANSWERS - 3 3. When you examine the fossil record you find trilobite eyes that have sophisticated aplanatic lenses that correct for spherical aberration. What is the significance of the fact that these trilobite eyes are among the very lowest eyes found as we examine the fossil record. It would take a lot of random evolutionary trials of mostly detrimental mutations to finally produce a sophisticated aplanatic lens that corrects for spherical aberation. These extended evolutionary trials would be expected to leave lots of fossils in the process of evolving aplanatic lenses, but they are not found, and it looks like the trilobite eye did not evolve.

REVIEW QUESTIONS AND ANSWERS - 4:

REVIEW QUESTIONS AND ANSWERS - 4 4. The optical system of the copepod Copilia consists of several lenses; the focusing system of the vertebrate eye consists of a number of parts; the same is the case for the system that controls the amount of light that enters the eye. What problem do these complex systems pose for a suggested evolutionary origin? It does not seem possible that a process of random mutations could gradually evolve these systems with so many interdependent parts that would be mostly useless until all the parts were present so as to provide some evolutionary survival value. The evolutionary process of natural selection would have been expected to favor those organisms that did not have the extra encumbrance of parts of developing systems that would have been useless until the systems were complete and functional.

REVIEW QUESTIONS AND ANSWERS - 5:

REVIEW QUESTIONS AND ANSWERS - 5 5. Some evolutionists (i.e. Nilsson and Pelger, 1994) have proposed a model of how the eye could evolve very fast. In fact they suggest that the eye could have evolved 1500 times since the Cambrian. They propose 1% arbitrary steps in improvement, especially changes in the shape of the eye. What is the main problem with their model? Give details. The main problem is that they did not include most of the essential parts of the eye in their estimates of the time required for an eye to evolve. Parts omitted include: 1. The retina (the most important and most complex part of the eye). 2. Brain parts needed to interpret what the eye sees. 3. Nerve connection between eye and brain. 4. Lens focusing mechanism. 5. Pupil size adjusting mechanism. 6. A functional lens (they make a vague suggestion). 7. New embryological process needed for vertebrates where the eye originates from the brain, not the skin, as they propose. 8. Muscles that move the eye.

REVIEW QUESTIONS AND ANSWERS - 6:

REVIEW QUESTIONS AND ANSWERS - 6 6. A number of leading evolutionists point out that the retina of the vertebrate eye is very badly designed because the light sensitive parts of the rods and cones are directed away from the incoming light. What appears to be the purpose of the inverted retina? What would happen if it weren’t inverted? The inverted retina permits the absorption of the light sensitive discs that the rods and cones are constantly producing. Furthermore it places the active disc producing ends of the rods and cones close to the blood supply of the choroid layer. If the retina were not inverted, and the light sensitive ends of the rods and cones were turned towards the light, what would perform the essential function of absorbing the discarded discs. These discs would eventually fill the eye and interfere with our ability to see.

ADDITIONAL REFERENCES:

ADDITIONAL REFERENCES Further discussion and many additional references for these topics can be found in the following publications by the author, Ariel A. Roth, Ph.D. 1. ORIGINS: LINKING SCIENCE AND SCRIPTURE . Hagerstown, MD. Review and Herald Publishing Association. 2. SCIENCE DISCOVERS GOD : Seven Convincing Lines of Evidence for His Existence. Hagerstown, MD. Autumn House Publishing, an imprint of Review and Herald Publishing Association. 3. Several articles published by the author can be found in the journal ORIGINS which the author edited for 23 years. For access see the Web Page of the Geoscience Research Institute www.grisda.org. 4. Other recommended URLs are: Earth History Research Center http://origins.swau.edu Theological Crossroads www.theox.org Sean Pitman www.detectingdesign.com Scientific Theology www.scientifictheology.com

USE PERMIT:

USE PERMIT Free personal use and non-commercial distribution of this material in its original publication medium is granted and encouraged. Permission for multiple printing for classroom use or presentations at public meetings is also freely allowed. In using any of this material appropriate attribution should be given especially for illustrations where credit is designated in the present discussions. Most illustrations are by the author and free use is granted for all media. However when credit to another source is given permission might be necessary for certain different kinds of communication entities.