> From: "Dunn Christopher" <CD295@psy.soton.ac.uk>
> Date: Thu, 23 May 1996 14:48:56 GMT
>
> The "Blind Watchmaker" is a metaphor for evolution insofar as the
> process of evolution and natural selection are "Blind" .Members of a
> species which possess a characteristic which increases their chance of
> survival over other members who do not possess this characteristic will
> have a better chance of surviving and passing on there genotype (their
> genetic code including the characteristic which aided their survival )
> to the next generation .This process is blind because it is random
> depending on a combination of many variables, including the
> environmental changes in temperature ,availability of food , predators
> to prey ratio ,shifting land masses and countless other factors .
>
> If members have a characteristic which enables them to adapt to changes
> in the environment successfully then they will survive and the gene
> that helped them survive will become dominant in successive generations
> , just as members who could not adapt due to their genotype will die
> without passing on there genotype .
Of course, this all onyl works if the trait that promoted survival and
successful reproduction was a genetically coded one, rather than a
chance variation in the growth process or the learning experience of the
organism.
> An example of the random factors of
> evolution can be seen in the case of the peppered moth which was a
> speckled white color as this characteristic camouflaged it as it rested
> on the bark of trees . During the industrial revolution a mutant form
> emerged which was much darker, and the white form of the moth began to
> declined .The reason for this decline and the dominance of the mutant
> form was smoke and soot from the many new factories darkened the bark
> of the trees ,making the previously camouflaged white moths stand out
> and easily predated by birds and the darker moths camouflaged against
> the darker bark thus much harder to spot by birds .So by changes in
> the environment the darker moths possessed a characteristic which
> enabled them to adapt and survive in the new environment. This is the
> "Blind Watchmaker" or evolution at work.
For an A, you need to relate this to other themes in the course, such as
free will or Universal Grammar.
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