Where memes are transmitted horizontally they can travel quite independently of the genes. An idea may be passed from one person to another, and then another, within one generation. Also memes may spread when they are useful, neutral or even positively harmful; such as an untrue explanation, an addictive habit, or a piece of malicious gossip. Only when horizontal transmission becomes common can the memes really be said to be independent of the genes.
Modern industrialised life is a world of horizontal transmission. We still learn our mother–tongue from our mothers, and many of our habits and ideals too. People are still overwhelmingly more likely to follow the religion of their parents than any other religion, and even to vote the same way as their parents did. However, our parents have less and less sway as we get older and we now go on learning more or less throughout our lives. Our main sources of information are sources that did not exist in our long evolutionary past: schools, radio, television, newspapers, books and magazines, and lots and lots of friends and acquaintances widely spread around the city, the country, and even the world.
The more ways there are for memes to spread, and the faster they can go, the less they are constrained by the needs of the genes. What determines the success of a meme in a traditional hunter–gatherer society, or even a simple farming society, is quite different from what determines its success in a modern industrialised society. In the former, life changes slowly, transmission is largely vertical, and a meme is most likely to succeed if it benefits (or at least appears to benefit) the health, longevity, and reproductive success of its carrier. In the latter, a meme is most likely to succeed if it can get quickly and efficiently from host to host, and never mind how well each host does in terms of either its own survival or its reproductive success – as long as there are more hosts around to infect. We now live in this latter kind of society and the memes have utterly changed – and continue to change – the way we live.
We can now return to the subject of sex and sex memes. For the sake of simplicity I am going to divide societies into just two types, realising that there are lots of gradations in between and few are purely one or the other. These are societies in which memes are largely transmitted
vertically and thus track the genes, and those in which they are transmitted horizontally and do not.
First, let us consider vertical transmission. There are many memes that ride on the back of biologically determined behaviours. They include all the memes that exploit biologically determined tendencies for mate choice and other aspects of sexual behaviour. From the examples given in the previous chapter we can easily guess at a lot of them: pictures of beautiful women with slim waists, long fair hair, bright eyes and symmetrical faces; films and videos of other people having sex, or of stories about other things with plenty of sex thrown in. Because people want to see these images, money can be made from them. Stories about jealous husbands and abandoned women will sell, as will love stories about pretty young nurses and clever, successful doctors (if you think these are a thing of the past go and look in the romance section of your local bookshop!).
Memes concerned with marriage are another obvious example. From fluffy white dresses and bunches of flowers, to defloration ceremonies and horrible punishments for adultery, we can understand many of the memes that surround marriage as being grounded in biological advantage. The American memeticist Aaron Lynch (1996) has provided many examples of marriage traditions that track biological advantage, including gender roles and patrilineal inheritance. The mechanism here is simple. People who practise a certain kind of marriage system will produce more children than those practising another, and so will pass on that system to their own, more numerous, children – so spreading that practice more effectively.
Moreover, the system that works best may vary with the environment. Socio–ecologists have provided many examples of unusual marriage arrangements, and of the varieties of bride prices and dowries, that actually seem to track the environment and enhance genetic fitness for the people who practise them. Polygyny (one man having several wives) is a common system, as is monogamy. But in extreme environments other systems can prevail. For example, the marginal, cold, and infertile valleys of the high Himalayas are one of the very few places in the world where fraternal polyandry occurs, that is, one woman marries two or more brothers who inherit the family land. Many men and women remain celibate; women usually helping on the estate, and unmarried men becoming monks. The British socio–ecologist John Crook (1989) has studied these people in detail and argued that their system does, in fact, maximise their genetic fitness. Grandmothers with polyandrous daughters were found to have more surviving offspring than those with monogamous daughters (Crook 1995).
Whether you look at this from a sociobiological perspective, or a memetic one, the outcome is similar. The successful practices (or successful memes) are those that provide the greatest genetic advantage in the given environment.
The same is true for some widespread sexual taboos. Masturbation has been seen as dirty, disgusting, revolting, and as sapping your ‘vital energy’. Generations of boys have been brought up to believe that ‘playing with themselves’ will make them go blind, or give them warts, or make hair grow on the palms of their hands. Given that young men have a strong desire for sex, dissuading them from masturbation is likely to increase the amount of vaginal sex they will have, thereby increasing the number of their offspring to whom they can pass on the taboo (Lynch 1996). Lynch suggests a similar explanation for the success of the circumcision meme, because circumcision makes masturbation more difficult, but not vaginal sex.
Interestingly, there are few, if any, taboos against female masturbation. Recent research shows that, though women masturbate less often than men, many masturbate once a week or more throughout most of their adult life (R. R. Baker 1996). The lack of a taboo makes sense because generally women cannot increase the number of their offspring by having more sex, so from this point of view it does not matter whether they masturbate or not.
The taboo against homosexuality follows the same logic. Most homosexuals are at least partly bisexual and can, with strongly wielded taboos, be persuaded to marry and have children, to whom they will pass on the taboo. Similarly, taboos against any kind of sexual practice that does not involve insemination can spread, including those against using birth control. Taboos against adultery work rather differently. Brodie (1996) suggests that it is in every man’s genetic interest to persuade other men
not
to commit adultery while doing so themselves. Thus both the anti–adultery memes and hypocrisy spread together.
Finally, there are many religions that make use of sex to spread themselves. A religion that promotes large families will, assuming vertical memetic transmission, produce more babies to grow up in that religion than one that promotes small families. Religious memes therefore become an important manipulator of genetic success. Catholicism’s taboo against birth control has been extremely effective in filling the world with millions of Catholics who bring up their children to believe that condoms and the pill are evil, and that God wants them to have as many children as possible.
Note that I said ‘assuming vertical memetic transmission’. All the
above 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 sexy 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 break down, and indeed this is exactly what is happening. As remote Himalayan villages come into contact with the rest of the world, young men are increasingly choosing not to share a wife with their brother but to opt for city life instead (Crook 1989).
The taboos also are no longer as effective as they once were. We may imagine a ‘masturbation taboo’ meme competing with a ‘masturbation is fun’ meme. The question of how many children the carriers of such memes produce is now completely irrelevant. People will pick up their memes from films, radio, books and television long before they have even produced any children, let alone persuaded their children to copy their own habits. So we should expect the power of all these sexual taboos to be reduced as horizontal transmission increases – as indeed appears to be the case.
The taboo against homosexuality is especially interesting. There is no generally accepted biological explanation of homosexuality and superficially it does not appear to be adaptive. Nevertheless, evidence is accumulating that there is an inherited predisposition for homosexuality. Assuming this is the case, the taboos of the past would, paradoxically, have favoured the survival of these genes by forcing the people who carried them, against their wishes, to marry and have children.
This suggests an interesting prediction for the future. As horizontal transmission increases the taboo should lose its power and so can be expected to disappear, as indeed it is doing in many societies. Homosexuals are then free to have sex with other homosexuals, to have long–term relationships with their own sex, and not to have children at all. The short–term effect is much more overt homosexual behaviour and acceptance of that behaviour by everyone, but the long–term effect may be fewer genes for homosexuality.
This analysis suggests that ancient sexual taboos should disappear, not as a function of wealth or industrialisation
per se,
but with increasing horizontal transmission. Thus, we would expect cultures with the least horizontal transmission to have the strongest taboos and vice versa. There are many indirect measures of horizontal transmission such as literacy rates, or the availability of telephones, radios and computers. More direct measures would be estimates of the average social group size, or the number of contacts that people make with others outside their immediate family. I would expect negative correlations between all these measures and the prevalence of sexual taboos. In this case, memetics provides predictions that do not make obvious sense within any other framework.
Celibacy
We can now return to those aspects of modern life that I suggested provided a special challenge to sociobiology; celibacy, birth control, and adoption.
Why would anyone voluntarily remain celibate and forego all the pleasures of sex? Unless they are constructed entirely differently from the rest of us, they will presumably have to fight hard against the natural desire to have loving physical relationships and to relieve the occasional, or even persistent and desperate need for sex. Celibate people cannot, by definition, pass on their genes. So why do they do it?
Genetic explanations are not impossible. Celibate men or women might, under some circumstances, better promote the survival of their genes by caring for siblings or nieces and nephews. This is known to happen in some territorial birds. For example, when territories are scarce young unmated males help at the nests of their siblings. They may get a territory of their own in future seasons, but for now helping out their nieces and nephews may genetically be the best bet. Certainly, among humans the loving maiden aunt and generous bachelor uncle are well known, and nepotism is common enough to warrant having its own name. Also, we have already considered one marriage system in which many people remain celibate but their genes still do better because of the impoverished environment.
So genes and environment might account for some kinds of celibacy but what about the celibate priest in a wealthy society? He cannot have inherited the celibate lifestyle genetically. He is unlikely to spend his time tending his brothers’ children and grandchildren, and his absence from the family is unlikely to benefit them by leaving more food for them to eat. If he is truly celibate (and, of course, many are not) his genes will die with him. Religious celibacy is a dead end for genes.