Darwin on Eye Evolution
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[edit] Introduction
Creationists often assert that Darwin's quote on eye evolution shows that evolution is false. The following excerpt can be found many creationist websites:
- "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 possible degree." - Charles Darwin, Origin of Species, 1st Ed., p. 186.
[edit] Refutation 1: Darwin only raises this point to smack it down
This excerpt is quote-mined, or in other words selectively taken out of context to express a remark contrary to what the author had intended.
The quote continues with the following:
- 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 ["the voice of the people is the voice of God "], 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 certain 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, should not be considered as subversive of the theory.
Darwin then goes on for several more pages describing how the eye could have formed in successive small steps from a small light-sensitive cell to the fully developed human eye, documenting many examples animals with eyes in these successive states [1].
As AnswersInGenesis euphemistically puts it, the quote is "subtly out of context" [2]. It is clear that Darwin himself did not believe that the evolution of the eye was absurd. His remark is characteristic of a fairly common writing style where, when presenting a theory, an author describes a possible criticism to his theory, followed immediately by a refutation of said criticism.
[edit] Refutation 2: Darwin who?
Behind this simple factual error, there lies a deep conceptual error characteristic of Creationists, who have the deepest difficulty in telling the difference between religion and science. If evolution was a religion of which Darwin was Supreme Prophet and UltraPope, and the Origin of Species was the Sacred Holy Text, then if Darwin had written that the eye couldn't evolve, that would be an end of the discussion.
However, evolution is science, and so Darwin had the first word on evolution, not the last. If he is respected by biologists, it is because he was the first person to really grasp and explain the theory of evolution --- but by that same token, since he was first, he was the evolutionary biologist who knew least about evolutionary biology; certainly less than biologists know today. If Darwin had found the evolution of the eye inexplicable (which, as we've seen, he didn't) that would not have prevented scientists over the past 150 years from coming up with a perfectly valid explanation.
[edit] Refutation 3: The evolution of the eye is easily explained
See our main article on Eye Evolution for details.
