I still remember the first time I read the allegation that our biological world was not merely clumsily cobbled together by evolutionary forces, but modern engineers could have designed better living systems. The assertion struck at the heart of the worldview asserting, “God saw all that he had made, and it was very good” (Genesis 1:31).
One such attack comes from Kenneth Miller and Richard Dawkins, who contend that the vertebrate eye contains a functional flaw.
Since the optic nerve in vertebrates extends over the retina instead of protruding out from the back of the eye, Miller has claimed that its “visual quality is degraded because light scatters as it passes through several layers of cellular wiring before reaching the retina.”/1 In Dawkin’s words, the retina is “wired in backwards” because light sensitive cells face away from incoming light thus revealing “the design of a complete idiot.”/2
In contrast to their derisive analysis, further examination of the eye’s organizational design reveals optimization for visual acuity. If retinal cells were turned around to aim directly at the incoming light as Miller and Dawkins propose, this design would interfere with the blood supply needed for high-quality vision. Solving this problem would then require capillaries to lie over these light sensitive cells resulting in even greater blockage of light than the optic nerve!
Sometimes it just takes time to discover our ignorance. As of 2010, it was discovered that special “glial cells” cover the retina. These cells channel light through the optic nerve wiring directly onto photoreceptor cells keeping images clear.
This is hardly a clumsy cobbled together biological system. Rather, the vertebrate eye produces the highest degree of vision quality revealing the work of a Master Craftsman.
1/ Kenneth Miller, “Life’s Grand Design,” Technology Review (February/March 1994), pp. 25-32.
2/ Richard Dawkins, The Greatest Show on Earth: The Evidence for Evolution (Free Press, 2009), p. 354.