The Blind Watchmaker is Dawkins' attempt to spell out the complexities
of evolution to those who remain convinced that human, and indeed all,
life was created by a mystical power with a specific design in mind.
The "Blind Watchmaker" is evolution, and as the analogy suggests, a
highly complex and intricate piece of equipment (ourselves) has been
"assembled" with no plan or purpose in mind. We are what we are because
over millions of years our bodies have gradually adapted to be able to
survive in whatever environment we find ourselves, that we are here is
tribute to the success of this process.
Variations which are incompatible with our environment generally signal
an early demise and little chance of the variation being passed on. All
variations are caused by mutations in the genes, with the mutating
process being directly influenced by factors such as radio activity,
X-rays or chemicals.
One of the reasons we find it so hard to understand the evolutionary
process is the timescale required for the minute changes to occur. The
changes are never radical, but infinitesimally small, taking millions
of generations to complete, to a society who has come to appreciate
fast food, same-day dry cleaning, electronic mail and the like, this
can be difficult to grasp.
To get over this timescale problem, Dawkins programmed a computer to
simulate cell division of plants and animals, with the influence of 9
genes causing variations in development. His "trees" grew symmetrically
to minimise the number of "genes" required, the trees developed in
different ways depending on which one of 9 "genes" influenced it.
By merging two programs, Development and Reproduction, a third larger
program is formed - Evolution. Repetitions (Evolution) of a tree are
passed down the generations with minor random errors (Reproduction),
the tree becomes less tree-like as it evolves. A programmer then
selects which of the offspring is most like the desired model, and
this is used for further reproduction, so this is not exactly natural
selection, more like selective breeding, but the programmer is doing
what the environment does in true evolution. This can explain how, for
instance, an eye developed, a mutation of cells produced some which
were sensitive to light, having these cells proved in some way
advantageous in that animals with them survived over animals without,
variations in the degree of photosensitivity led to greater
advantages.
The creationist argument against Darwin's explanation of how we
acquired this highly specialised organ suggests that if it gradually
developed over many millions of years, at some time it cannot have been
very good at seeing. If it was not very good at its job, then what was
the point of it? This argument fails to take account of two facts,
firstly, although we may think we have perfect vision, we are not the
end article, we are still evolving as are all other plants and animals.
If at some stage in the future it becomes necessary for us to have
infra red or ultra violet vision or to see radio waves (for
example!!), then we may go on to develop in this way, because those
members of the species which show the merest hint of these abilities
will survive over those who do not, and the traits will be passed on.
Secondly, if for arguments sake, we have 100% vision now, at some early
stage of development we had less, perhaps only 25% of what we have now,
but we would not have considered it deficient for we would not have
known it could be better. If we develop infra red visual ability in the
future, it will not diminish our visual ability now. The
characteristics we have now, have evolved because of their
compatibility with our environment, when that changes, so will we.
What is important is that the random variations caused by mutating
genes only become part of our genetic make-up through natural
selection, there may be a component of mate preference for some
characteristics whereby a female finds the characteristic attractive,
chooses the mate with that characteristic, and increases the population
having it by doing so. Dawkins further suggests that the preference for
a characteristic may be genetically programmed, passed down by the
father who has the characteristic, and the mother who selected her mate
because of it. We are what our genes make us.
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