Weasel Program - Criticism

Criticism

Dawkins's "weasel program" has been the subject of much debate. Intelligent Design proponent William A. Dembski has criticized its assumption that the intermittent stages of such a progression will be selected by evolutionary principles, and asserts that many genes that are useful in tandem would not have arisen independently. It is often suggested that the program works by "locking" a correct letter when it is found. Robert C. Newman, for example, misunderstands the basic algorithm:

For Dawkins, once the computer gets a particular character right, it never allows mutation to work on that character again.

(Mere Creation, p 437)

This misunderstanding has been frequently repeated in the creationist and ID community. Creation Ministries claims that "Once a letter falls into place, Dawkin's program ensures it won't mutate away". While this is not strictly correct, as the 8th iteration of the sample run to the right shows, the conservation of overall similarity to a target of a kind that Dawkins himself acknowledges is foreign to the evolutionary process seems to be a valid caution against accepting the model as a proof, rather than an interesting demonstration of the way characters could be preserved from generation to generation given an appropriate selection mechanism.

Dawkins broached several of these issues himself in The Blind Watchmaker, and has also responded to these criticisms by pointing out that the program was never intended to model biological evolution accurately, and that he very specifically described it as an artificial selection process from the outset, as the citation above shows. It was only meant to demonstrate the power of cumulative selection as compared to random selection, and show the complete unrealism of the popular notion of natural selection as "monkeys pounding on typewriters". These cautions need to be borne in mind as a qualification of Dawkins' enthusiastic rhetorical use of the model in The Blind Watchmaker.

The answer to this criticism is that it is the environment and favorable conditions as well as the higher number of mating events compared to mutation events in a given period of time that "lock" traits of a given species into place. Once a species has evolved a core set of traits that optimize it for an environment, it is unlikely to drift much for millions of years unless there is a drastic change in environmental conditions that prevent the traits from being useful, and even random mutations will be over-ruled by the larger number of instances of mating (where mutated genes will be more likely set back to the status of fellow species without the mutated trait) than the number of mutations in a given period of time. Only large numbers of mutations or a drastically changed environment for a long enough period of time can over-rule the stability of a species gene pool that is always shuffled slightly back to its norm by breeding events. In the case of the weasel program, it is the readability of the evolved sentence and its recognition as a quote from Shakespeare by humans that simulate this process.