Re: "The Selfish Gene"

From: Liz Lee (
Date: Mon Oct 13 1997 - 21:39:06 BST

The Selfish Gene.

That we exist at all is the result of chance conditions (lightning) acting
with existing compounds (water, ammonia etc) to produce more complex
molecules such as amino acids (C,H,O,N and sometimes S and P) from which
proteins are formed. These protein molecules become concentrated in areas
such as at the water's edge, and under the influence of UV light combine to
become larger. At some point, a particular type of molecule was formed, by
chance, which had the ability to make copies of itself, this ability was in
turn passed to each of the identical copies. These replicating molecules
rapidly spread, increasing their proportion through the population. With
time, and the vast number of replicas all reproducing, a chance mistake led
to variations in the molecules, and these variations led to greater and more
diverse variations in their turn. Some of the variations were less likely to
break up than others, because they were more stable they had longer to make
copies of themselves and therefore became more numerous. This was the
evolution of complex, replicating molecules.

As more and more replications and variations were made, the raw materials for
building became scarcer, molecules which could obtain the raw materials were
at an advantage as they carried on replicating to the detriment of those less
competitive. Breaking up other molecules led to a ready source of nutrition
to aid reproduction, and reduced the competition. Other measures, such as
protection against would-be "wreckers", led to a defensive strategy, by
building a protein wall around the molecule they were more likely to survive.
Thus, a primitive cell was formed, by becoming mobile, the cell was able to
travel further to obtain food, and to avoid attack from others. So the
original molecule, able to replicate itself, has now constructed a vehicle to
protect and propel itself.

The molecules above are not dissimilar in structure to the nucleotides which
make up DNA, consisting of C,H,O,N and P. The nucleotides Adenine,
Cytosine, Guanine, and Thymine are the defining features of the genes, their
sequence determines the species and individual characteristics. Genes have
wide-ranging effects, from determining hair and eye colour, to influencing
mate preference, the crucial point is that a single gene may have different
effects on different parts of the body, and the body in turn is affected by
many different genes. The genes are not a neatly defined entity, they are
portions of chromosomes where the pattern of A,C,G and T is repeated
according to natural selection. The genes which are most stable (often
smaller sequences) have longer lives, this is because the smaller the genetic
unit, the less likely it is to be split during the "crossing over" of genes
in gamete production. This crossing over allows gene recombination and
guarantees infinite variability within species . So genes are the modern
equivalents of the complex proteins above, and we, and all plants and
animals, are their vehicles or as Dawkins puts it their "survival machines."

Our genes "programme" us to behave in ways which enhance our chances of
survival, and therefore the genes' survival, the older the gene, the more
people that are likely to share it. For instance, the gene for
left-handedness is shared by approximately 10% of the population, whereas the
gene for dwarfism is much less common. A gene which causes death in
childhood is unlikely to survive, but a gene for liking sweet substances,
which ensured survival when sugar was rare but essential, has survived from
the EEA. We have evolved to choose a mate we find attractive, enjoy sex,
desire children, protect and nurture our young and behave altruistically
towards relatives (if the costs do not outweigh the benefits), all behaviours
which have been programmed by our genes. All these behaviours increase the
probability that our genes will be passed on to the next generation, at the
expense of other individuals' genes. Genes influence us to perform
strategies such as "protect your mate", this strategy remains stable as long
as the majority of the population follow it, if it is open to individuals who
"cheat", by running off and finding another mate when threatened, it may stop
being stable as the number of individuals with the gene "run away" increases.
These Evolutionary Stable Strategies are performed dependant on their costs
and benefits, if the cost of protecting your mate outweighs the benefits (you
might get badly beaten up or even killed) then the alternate strategy, run
away, will be more attractive, but getting another mate might not be so easy,
so the relative values determine which strategy wins.

Dawkins suggests the gene acts in a selfish way because its sole interest is
survival of self, it will ensure the survival machine is programmed to
maximise the likelihood of passing on genes from one generation to the next,
in some circumstances this may not be your own genes, but those of a close
relative. This explanation accounts for grandmothers' altruism (especially to
daughters' children) and care of a younger sibling at the expense of
reproduction. The message Dawkins is getting over is that the genes, as
replicating units are the dominating force in nature, the genes which are
poor at replicating do not survive, the better replicators become ever more
numerous, they have no ultimate goal, their raison d'etre is to be, and to
continue to be in the future.

This archive was generated by hypermail 2b30 : Tue Feb 13 2001 - 16:23:08 GMT