Posted by jlwile on May 11, 2010
Many evolutionists have claimed that the human eye (actually the vertebrate eye in general) is wired “backwards.” According to evolutionists, this is such a terrible way to make an eye that it clearly shows the eye has no Designer. What is so “terrible” about the way the eye is wired? Well, light that enters the eye is detected by specialized cells called rods and cones. Those rods and cones convert the light that they detect into signals that travel through association neurons and into nerve fibers that carry the signals to the brain. As shown in the illustration above, however, the neurons and nerves that carry those signals are in front of the rods and cones. Thus, light must travel through the nerves and association neurons before it can hit the rods and cones.
According to evolutionists, this is a terrible design. After all, if anyone with any sense were to design an eye, the rods and cones would be the first thing the light hits. That way, the rods and cones would get an unobstructed view of the light. Since the vertebrate eye is not designed the way these evolutionists think should be “obvious,” it is clear (to them) that the eye was not designed. Indeed, in his book The Blind Watchmaker (probably his best work), Richard Dawkins says:
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.1
Of course, like most evolutionary nonsense, the more science we learn, the more we see how wrong this argument is.
As far back as 2007, evidence emerged that showed there was something wrong with the evolutionists’ argument. Franze and his colleagues discovered that certain cells in the retina (Muller cells) act as optical fibers, funneling light right to the rods and cones.2 Now Labin and Ribak have modeled the dynamics of this system, and they conclude:
The retina is revealed as an optimal structure designed for improving the sharpness of images.3
Why is this an “optimal” design for the eye? It’s actually quite amazing. There are two kinds of light that the rods and cones detect: light coming into the eye from the scene of interest, and light that has been scattered within the eye itself. Obviously, the sharpest image will be formed if the light from the scene is the only light allowed to reach the rods and cones. In other words, to form the best image possible, the scattered light (think of it as “noise”) must be filtered out. Well, that’s exactly what the Muller cells do, according to Labin and Ribak!
So despite what evolutionists have claimed, the vertebrate eye is, in fact, designed incredibly well. It is designed to provide the sharpest images possible. As an article in New Scientist says:
IT LOOKS wrong, but the strange, “backwards” structure of the vertebrate retina actually improves vision.
If the eye were designed according to what many evolutionists have said is the obviously superior design (with light hitting the rods and cones first), we would not see things as sharply as we do now.
Now, of course, this is what creationists have maintained for a long, long time. As Dr. George Marshall, creationist and Sir Jules Thorn Lecturer in Ophthalmic Science at the University of Glasgow, said back in 1996:
The idea that the eye is wired backward comes from a lack of knowledge of eye function and anatomy.
Indeed, that turns out to be exactly right. Since science was ignorant of what Muller cells do in the retina, evolutionary scientists jumped to the erroneous conclusion that the vertebrate eye was poorly designed. Creationists consistently argued against such a silly notion, and as usual, the creationist position has been confirmed by the data.
So will evolutionists give up on this erroneous argument? Of course not, because their preconceived notions are more important to them than the scientific data. For example, Dr. Kenneth Miller has already said:
The shape, orientation and structure of the Müller cells help the retina to overcome one of the principal shortcomings of its inside-out wiring
In other words, despite the evidence, he still wants to believe that the vertebrate eye is wired in the wrong way. However, through the awesome power of mutation acted on by natural selection, he believes that evolution has developed a “workaround” for the problem. In addition, this “workaround” just happens to produce superior vision compared to what would be achieved by the design Miller thinks is more reasonable!
Of course, the more scientific position to take would be to follow the data and conclude that the vertebrate eye has been specifically designed to provide the best vision possible. Don’t expect most evolutionists to suddenly adopt the more scientific position, however. After all, if they made a habit of that, they would no longer be evolutionists!
1. Richard Dawkins, The Blind Watchmaker: Why the Evidence of Evolution Reveals a Universe Without Design, W. W. Norton & Company, p. 93, 1996
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2. Franze K, Grosche J, Skatchkov SN, Schinkinger S, Foja C, Schild D, Uckermann O, Travis K, Reichenbach A, Guck J, “Muller cells are living optical fibers in the vertebrate retina,” Proc Natl Acad Sci USA 104:8287-92, 2007
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3. A. M. Labin and E. N. Ribak, “Retinal Glial Cells Enhance Human Vision Acuity” Phys. Rev. Lett. 104:158102, 2010
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