In his book The Making of the Fittest: DNA and the Ultimate Forensic Record of Evolution, evolutionist Sean Carroll makes the usual claims about how we can know evolution is true. According to Carroll, there is no doubt, evolution is decisively confirmed, it is beyond any doubt, and so forth. As if to prove these high claims Carroll presents a variety of genetic evidences and arguments. But his examples routinely fail and indeed raise profound problems for evolution. The evolution genre is a sort of modern day version of the Emperor's New Clothes. It is a fascinating study in contrasts, for it reveals a well educated, intelligentsia gone awry.
One of Carroll's evidences involves vision, and a particular gene that determines the color of the light that is detected. [see pages 103-107] This gene encodes a protein that is found in the hundreds of millions of photocells in our retina. The photocells shaped like a cone come in three types, depending on which color they detect: red, green or blue. By combining the signals from these different photocells, our brain can assemble a full color image. The whole system is phenomenally complex, and might seem to be an unlikely subject to use as compelling evidence for evolution.
Carroll's point is that it is easy for him to envision how we came to have our particular color coding genes. For instance, two of them are adjacent in the genome. Isn't this evidence that one arose from the other via gene duplication? After the duplication event only a few mutations would be needed to settle on their respective color codings. Is this not compelling evidence for evolution by natural selection?
The story continues, but it doesn't get any better, and it is remarkable that Carroll thinks this example helps make evolution compelling. First, there is no compelling reason why one should accept Carroll's evolutionary interpretation of the data. Evolutionists are ensconsed in their theory, and often have difficulty understanding why others do not understand that all life simply evolved. Carroll is convinced of this evidence, but in fact he has not provided good reasons to be so swayed, for those who do not already believe in evolution.
Beyond this, his evidence raises profound problems for evolution. Most obviously, Carroll takes for granted the pre existence of the color-coding gene, the photocells, the retina, and the remainder of the vision system and brain. From where did this incredible system come? Are we to believe that it too is simply the result of evolution because Carroll thinks a gene duplication event added more color resolution?
Another problem is that Carroll vastly underestimates the complexity of the supposed evolutionary change he proposes. A new color-coding gene followed by a few mutations does not instantly provide enhanced color resolution as Carroll suggests. That is only the beginning of what would be required. The product of the new color-coding gene would need to be used in certain photocells. The quantity and locations of these photocells are important.
And on the receiving end, downstream cells would need to be reprogrammed, to interpret properly the new color information. This is because the photocells do not signal their color. The output of the photocell is merely a nerve impulse (action potential), and its interpretation is an extremely complex process. Modifying a color-coding gene without concomitant downstream reprogramming just confuses things.
With evolution all this complexity is irrelevant. Evolution presents a just-add-water view of biology that does not do justice to the science or the scientists. It is a fascinating study in contrasts.