The Creation Wiki is made available by the NW Creation Network
Watch monthly live webcast - Like us on Facebook - Subscribe on YouTube

The eye is too complex to have evolved (Talk.Origins)

From CreationWiki, the encyclopedia of creation science
Jump to: navigation, search
Response Article
This article (The eye is too complex to have evolved (Talk.Origins)) is a response to a rebuttal of a creationist claim published by Talk.Origins Archive under the title Index to Creationist Claims.

Claim CB301:

The eye is too complex to have evolved.


CreationWiki response:

(Talk.Origins quotes in blue)

1. This is the quintessential example of the argument from incredulity. The source making the claim usually quotes Darwin saying that the evolution of the eye seems "absurd in the highest degree". However, Darwin follows that statement with a three-and-a-half-page proposal of intermediate stages through which eyes might have evolved via gradual steps (Darwin 1872).

  • photosensitive cell
  • aggregates of pigment cells without a nerve
  • an optic nerve surrounded by pigment cells and covered by translucent skin
  • pigment cells forming a small depression
  • pigment cells forming a deeper depression
  • the skin over the depression taking a lens shape
  • muscles allowing the lens to adjust

All of these steps are known to be viable because all exist in animals living today. The increments between these steps are slight and may be broken down into even smaller increments. Natural selection should, under many circumstances, favor the increments. Since eyes do not fossilize well, we do not know that the development of the eye followed exactly that path, but we certainly cannot claim that no path exists.

While it is true that Brown refers to Darwin’s famous quote, he also makes reference to Darwin’s proposed scenario. That said, it is clear that Talk Origins does not understand the argument. It is not that no one can invent a plausible sounding scenario, but that natural processes cannot produce organized complex systems. This is supported by Thermodynamics which, when studied statistically, shows a tendency towards randomness and disorder, particularly when energy is applied randomly.

The invention of a plausible sounding scenario, even with events based on an existing state, does not change this. Any talented science fiction writer can make impossible events sound plausible. As an example here is a description of how a fork can evolve from a round metal rod.

  • Round metal rod.
  • Flattened metal rod.
  • Metal rod flattened more at one end than the other.
  • A knife.
  • A spatula
  • A spatula with a curved up end
  • A spatula with a slightly rounded and curved up end.
  • A spoon.
  • A spork.
  • A fork.

Now all of these objects actually exist, and are useful, so based on Talk Origins’ rationale it has just been proved that a fork could have naturally evolved from a round metal rod.

Evidence for one step in the evolution of the vertebrate eye comes from comparative anatomy and genetics. The vertebrate βγ-crystallin genes, which code for several proteins crucial for the lens, are very similar to the Ciona βγ-crystallin gene. Ciona is an urochordate, a distant relative of vertebrates. Ciona's single βγ-crystallin gene is expressed in its otolith, a pigmented sister cell of the light-sensing ocellus. The origin of the lens appears to be based on co-optation of previously existing elements in a lensless system.

Were these genes named before or after the factions of both genes were known? If just one was named after the functions of both genes were known, then evolution was assumed in the naming process and thus it is not evidence of anything.

Even if they were named on the basis of nuclide and/or location similarity, functional similarity would be sufficient to explain the similarity of genes, but it would also be consistent with common decent.

Nilsson and Pelger (1994) calculated that if each step were a 1 percent change, the evolution of the eye would take 1,829 steps, which could happen in 364,000 generations.

The Geoscience Research Institute has commented on this article[1]:

"What is one to make of all this? First, comparing the evolution of the eye to shape changes on a computer screen seems rather far-fetched. The entire project seems closer to an exercise in geometry than in biology. Second, the exercise assumes a functional starting point. Thus it has nothing to do with the origin of the biochemical systems of vision or the requisite neural network. Third, Nilsson and Pelger's computer exercise operates as if each 1% change in morphology can be accounted for by a single gene mutation. They do not consider the effects of pleiotropy, genetic background, or developmental processes. Fourth, an important part of the model relies on the special circumstance of a layer of clear cells covering the "retina." This layer somehow assumes the proper shape of a lens. Fifth, as noted by the authors, several features of the eye remain unaccounted for, such as the iris. Basically, the only result achieved was to show that two light-sensitive surfaces that differ in shape by 1% will have different efficiencies in photoreception, and that an uninterrupted series of 1% improvements is possible. The failure of scientists to produce new structures in selection experiments illustrates the implausibility of Nilsson and Pelger's "just so" story."

And if you walked at a rate of one step per second, you could walk to the Moon in just 42 years.

The point is that such calculations do not make something possible.

This estimate not only assumes that all of the steps are viable, but that none are reversed or made in a different direction. It does not seem to consider the number of genetic changes needed for each step, since it is clear that a 1% change in genetic information at any step would require many bits of ‘new'’' genetic information. When genetic information is considered it becomes clear that this estimate is extremely low.

Furthermore it does not matter how many steps there are or even how small those steps are; the notion that the information needed to make an eye could result from random mutations violates both Thermodynamics and Information theory.

The problem of evolving an eye or any other complex organ where none existed cannot be solved by inventing plausible sounding scenarios. To make their case Evolutionists need to show that the information needed to make such structures can come form random mutations and a selection process that does not contain the information in any form.

Finally, one thing Talk Origins totally ignores is that for an eye to work it has to be able to send the images to a brain that is capable of accurately interpreting the signals from the eyes so as to form an image in the mind. Furthermore, for any of the eye’s alleged ancestral forms to have any benefit they too need to be plugged into a brain capable of receiving and properly processing the signals. So the entire process is not just getting a camera to see through but the ability to use that camera as well.