The Meme Machine

136 THE MEME MACHINE
arguments depend on parents passing on their memes to their children, because
only in this case does the number of children you have determine the success of
your memes. Vertical transmission was probably a major route of memetic
replication throughout most of our evolutionary history. Early humans probably
lived in groups of about one to two hundred at most. They may have
communicated with many of the group, but they would have been unlikely to
communicate much more widely than that. As far as we can tell, cultural
traditions changed very slowly for thousands of years and so the memes that
parents passed on to their children would have continued to be the prevalent
ones throughout the children’s lifetime. In this situation, the successful memes
would, to a large extent, be the ones that were also of biological advantage.
In examples like these the sociobiological and memetic explanations barely
differ. They do not make different predictions. There is no particular advantage
to the memetic viewpoint, and we might as well stick with sociobiology.
However, transmission is no longer largely vertical. So what happens to sex
when memes are generally spread horizontally? The simple answer is that
biological advantage becomes less and less relevant. Let us take the first type of
sex meme that I mentioned: the pictures of sexier women and the heart-rending
love stories. These are not affected because they depend on biologically inbuilt
tendencies that will not quickly go away. Even though we now spread most of
our memes horizontally, we still have much the same brains as people did five
hundred years ago or even five thousand years ago. We just do like tall, dark,
strong hunks, and slim, bright-eyed females. We just are turned on by watching
sex or thinking about our ideal lover while masturbating.
The same is not true of social institutions like marriage practices. Nowadays,
what determines the memetic success of a marriage practice is not how many
children it produces. Horizontal transmission is now so fast that it outstrips
vertical transmission and people can choose what kind of marriage system to
adopt from any they happen to have come across, including none at all. The
number of children produced by their parents’ marriage system is now
irrelevant. Monogamous marriage has survived a long time and is still prevalent
even in technologically advanced societies. But it is clearly under pressure, with
divorce rates reaching nearly 50 per cent in many countries, and some young
people rejecting the ‘ideal’ of marriage altogether.
I mentioned the rare practice of fraternal polyandry which increases genetic
success in some parts of the Himalayas. With increasing access to city lifestyles
and more horizontally transmitted memes we might expect such a system to