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Darwin and Evolution of the Eye

QUESTION: What did Darwin say about the Evolution of the Eye?

ANSWER:

When it comes to the evolution of the eye, Charles Darwin made the following declaration:

“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.”

This is a profound statement that stands on its own when we view the human eye with the latest in scientific and technological tools.

What else did Darwin say about the Evolution of the Eye?
However, to be fair, Charles Darwin continued his statement regarding the improbable evolution of the eye:

“Yet reason tells me, that if numerous gradations from a perfect and complex eye to one very imperfect and simple, each grade being useful to its possessor, can be shown to exist; if further, the eye does vary ever so slightly, and the variations be inherited, which is certainly the case; and if any variation or modification in the organ be ever useful to an animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, can hardly be considered real.”

In context, Darwin maintains that the evolution of the complex eye is possible (although highly improbable) if science later establishes numerous, connected gradations from simple to complex in the fossil record. Read this section of Darwin’s theory for yourself and see where you land on the issue. Has the fossil record made the case? With our current understanding of the codependent complexity of the human eye, optic nerve, and visual cortex, is it really possible for the optic nub on the end of an earth worm to become the human eye?

NOTE:
Charles Darwin, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life, 1859 (Bantam Classic edition, 1999), pp. 155-56.

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