PLEASE NOTE: for "a few million years" read "an unknown period of
time which may only have been about an hour and a half if lady luck
was feeling particularly clever that day"
chapter 1
he gives a few examples of altruism in animals, such as worker
bees stinging intruders to their hives and thereby dying
themselves and birds giving alarm calls which draw attention
to themselves but mean a greater chance of survival to the
rest of the flock, and says that the traditional view of these acts
was that they were done "for the good of the species." the rest of
the book is dedicated to the argument that they are in fact done for
the good of the genes.
chapter 2
the argument (strangely enough) began at the beginning (of life).
in the primordial soup the molecules were swilling about stealing
bits off each other with their ionic charges for a few million years
when all of a sudden a molecule came into existence that had its
ionic charges arranged in such a way that the pieces of other
molecules that it attracted happened to be the same as the things it
was made up of itself. it was therefor able to make exact copies of
itself. this type of molecule is called a "replicator." this molecule
became increasingly common as it continued to replicate itself.
however it didnt always make an exact copy of itself, sometimes one
of the bits it attracted to itself was the wrong way round or maybe
even the wrong thing altogether. this process is called mutation. the
resulting molecule may be unable to replicate itself but it may in
fact be a better replicator than the original. this led to
competition between the different replicators for the building block
molecules. the replicators which were most stable and/or were
quickest and/or most accurate at replicating are would have become
more common which is a measure of how successful they were as
replicators. those which were also strong enough to pull the bits
they wanted out of other replicators would have been even more
successful as they would have been decreasing the number of
competitors at the same time as increasing the numbers of its own
kind. this is an early example of selfishness on a biochemical level.
after a few million years of mutation a replicator evolved that was
protected within a wall of protein to stop other replicators from
pulling it apart. these walls would however still have to be able to
allow some molecules in with which the replicator could replicate
itself. it would of course only want certain types of molecules with
which to do this.the more successful replicators would then be the
ones whose walls would let in only those molecules which it needed in
order to replicate and even let out the waste products that it no
longer needed.
these then were the first cells, little "survival machines" which the
replicators sat in and replicated all day. from these cells developed
the first animals, and, consequently, all life on earth.
chapter 3
an important point to remember is that even at this early stage the
replicator contained a code which was like a recipe for how the
survival machines were made. that is to say the structure of
the survival machines depended entirely upon the structure of the
replicator. each small length of a replicator strand which changes a
certain trait of the survival machine can be called a gene.
after a few million more years of mutation some replicators' survival
machines had developed the ability to sense the chemical composition
of the soup around them and within a few million years they were able
to sense the movements within the soup and a few million years later,
what the soup actually looked like. by this time the survival
machines were made up of many hundreds of cells, each with its own
specialized task and each containing a copy of the replicator which
made it.
at some point around this time (give or take a few million
years) a certain gene, on a certain mutated coded replicator strand
told its survival machine (actually i think ill start calling them
animals at this point (cos its quicker to type)) that it was no
longer going to reproduce itself exactly, it was going to combine
its replicator strand with that of another survival machine and
thereby the resultant animal would have some traits from each of the
parents. this turned out to be (in the words of mr dawkins himself) a
"notable triumph of survival machine technology," as it meant that
the successful traits of animals could be combined in animals with
new unique combinations which may be, and often have been, more
successful than either of the parents.
it was however not only a triumph for the future of the animal
population in general but also for the particular gene in question,
as it meant that in all successive animals would split their
replicator strands up thus causing the death of many individual
genes, which are effectively the enemies of the so called "sexual
reproduction gene." this is one of few examples of a gene being
selfish towards other genes within the same body as itself.
im afraid thats all youre getting. sorry most of its too detailed and
the end is a bit rushed but thats the way i(t) goes.
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