The most commonly used argument against Darwinism and for Intelligent Design is the human eye and it’s complexity. How did the human eye evolve? How does this change the strength of the argument of Intelligent Design as a scientific theory?
There are currently two competing theories as to how life on Earth came about, Darwinism, evolution and natural selection, and Intelligent Design, some great architect creating life. The most promising evidence for Intelligent Design had been the human eye and the argument that the independent pieces (the retina, lens…) had to have come about all at once for organisms to see. However, scientists have a theory as to how the eye evolved, creating a disturbance in the most prominent argument of Intelligent Design.
Diagram of Evolution of the Human Eye
Here’s the theory for the evolution of the eye: the original “eye” was a collection of cells on the skin (that curved inward like an eye socket) that helped organisms to “see” light, helping it to “see” if any other organism was in that direction because of the break in the light that the organism saw. Eventually the amount of light that the cells could detect was narrowed to give organisms better direction. And from this the cells became a retina, which helped the organism see even more clearly. Finally, the eye grew a lens that helped the organism to see even more clearly. We can even see these different stages of eye development in living species today.
And so, due to evidence of the evolution of the human eye, Intelligent Design loses its most promising argument. If there had been any disagreements as to whether Intelligent Design was a scientific theory, we now see that by ripping apart it's best argument it leaves us with a new term for creationism.
For more information on the argument against Intelligent Design see:
For more information on Evolution pick up Your Inner Fish: A Journey Into the 3.5 Billion Year History of the Human Body- Neil Shuban.