origin of light-sensitivity (The atheist delusion)

by George Jelliss , Crewe, Sunday, January 27, 2008, 16:13 (5932 days ago) @ dhw

You write: "I'm afraid I shall need to eat a lot more carrots before I can cope with the other article!" But there is very little to "cope" with there but basic chemistry. You cannot possibly hope to understand modern biology without at least a basic understanding of chemistry. - In chapter 3, on Evolution, you have "In this context of physical change, natural selection explains nothing, because although it tells us why beneficial changes survive and are perpetuated, and indeed why organs will improve over time, it does not explain the mechanism that enables such changes to take place." and: "The miracle lies in the original, primitive, light-sensitive "nerve", which if it did not already provide some degree of advantage ... even 0.0001% of human vision ... would not have survived. This may have been "simple" by comparison with later eyes, but it remains inexplicable." - But it is not a miracle nor is it inexplicable. It is explained by an understanding of the biochemistry within cells. This is of course something that we have developed since Darwin's day. Darwin, as you have shown in several quotes, was not able to say exactly how a light-sensitive spot might develop, and confined his theory to how natural selection would act to preserve such an advantageous variation. But now we can say how such a change could occur. - Most biochemistry only involves the elements H, C, N, O (with others occasionally) and mostly involves chains of carbon atoms (C) with hydrogen atoms (H) attached to the unused bonds. That's what the lines of bonds in the diagrams are a shorthand for. It's not that difficult to comprehend.