richard_dawkins_-_the_god_delusion

T H E R O O T S OF RELIGION 197
'memeplexes'. As usual with memes, we gain understanding by
going back to the genetic origin of the analogy.
For didactic purposes, I treated genes as though they were
isolated units, acting independently. But of course they are not independent
of one another, and this fact shows itself in two ways.
First, genes are linearly strung along chromosomes, and so tend to
travel through generations in the company of particular other genes
that occupy neighbouring chromosomal loci. We doctors call that
kind of linkage linkage, and I shall say no more about it because
memes don't have chromosomes, alleles or sexual recombination.
The other respect in which genes are not independent is very
different from genetic linkage, and here there is a good memetic
analogy. It concerns embryology which - the fact is often misunderstood
- is completely distinct from genetics. Bodies are not
jigsawed together as mosaics of phenotypic pieces, each one contributed
by a different gene. There is no one-to-one mapping
between genes and units of anatomy or behaviour. Genes
'collaborate' with hundreds of other genes in programming the
developmental processes that culminate in a body, in the same kind
of way as the words of a recipe collaborate in a cookery process
that culminates in a dish. It is not the case that each word of the
recipe corresponds to a different morsel of the dish.
Genes, then, co-operate in cartels to build bodies, and that is one
of the important principles of embryology. It is tempting to say that
natural selection favours cartels of genes in a kind of group
selection between alternative cartels. That is confusion. What really
happens is that the other genes of the gene pool constitute a major
part of the environment in which each gene is selected versus its
alleles. Because each is selected to be successful in the presence of
the others - which are also being selected in a similar way - cartels
of co-operating genes emerge. We have here something more like a
free market than a planned economy. There is a butcher and
a baker, but perhaps a gap in the market for a candlestick maker.
The invisible hand of natural selection fills the gap. That is different
from having a central planner who favours the troika of butcher
+ baker + candlestick maker. The idea of co-operating cartels
assembled by the invisible hand will turn out to be central to our
understanding of religious memes and how they work.