There is no room for such a leash on the memetic view. If memes are replicators in their own right then they will spread and spread entirely selfishly. They will also spread faster and faster, and the number of memes will go on increasing. If the genes ever could track the memes there must come a point at which they can no longer do so, and the speed of memetic evolution leaves the genes far behind.
In today’s world a very few people still live as hunter–gatherers; many live as farmers or industrial workers in rapidly changing countries; and some live as advanced spreaders of memes in societies with computers, mobile phones, and television. Birth rates are highest in the developing countries and lowest in the technologically advanced ones, so at the moment, memetic pressures favour the genes of people living in undeveloped countries. Since their genes differ very slightly from the genes of people in developed countries, this will have some effect on the overall gene pool. However, for this to have a big effect, the selection pressure would have to remain stable for many generations and, given the rate of cultural change, this now seems unlikely. So what might we expect to happen now?
For most of the past two or three million years memes have evolved slowly. Their main effect on the genes occurred because people tended to mate with good imitators, but beyond that they did not affect sexual behaviour very much. Our sexual behaviour was largely driven by the
genes for their own replication, and our sexuality still shows the legacy of this long process. However, in the modern world, the memes have taken over much of our sexual behaviour and put it to work for their propagation instead. The technology of birth control has been an extraordinarily successful set of memes, facilitating the sex industry and diverting people’s energies away from lifelong child rearing. However, just like genes, the memes have no foresight. They cannot be expected to foresee that almost anything might happen. They might even, in the process of diverting our energies from the genes, just wipe us out.
Actually, this possibility is remote for the following reason. If birth rates over the whole planet fall then the total population will fall. This will be good news for the rest of the biosphere, but bad news for the memes. At some point, the density of population will be too low to sustain the infrastructure needed for a thriving memetic world, and so memetic driving will slow down, and with it the use of birth control. The genes can then take over and build up the population again until a new memetic infestation takes place. As is seen with the spread of many parasites and diseases, it is rare for them to wipe out their hosts completely, and I would not expect memes to do so either.
In fact, the situation is far more complex and unpredictable than that. Given the gross inequities between societies at the moment it is more likely that birth rates will continue falling in the technologically advanced societies, while the less advanced ones grow in population. Memetic influence may then shift towards the previously undeveloped countries and birth rates start falling there. So we might expect a swing back and forth as memes and genes battle it out to get human beings to spend their lives replicating one or the other. This is what it means to be creatures of two competing replicators.
Finally, the memes are busy devising ways of interfering even more directly with the genes. We are already creating genetically engineered vegetables for food and, memetic pressure groups notwithstanding, will probably create genetically engineered animals that are quick growing, delicious to eat, and do not object to their impoverished or miserable lives.
DNA testing means that paternity can be assured so that women will find it harder to trick their partners into raising other men’s children and men will have to pay the cost of having children by casual relationships. Our sexual desires will still follow the dictates of genetic evolution while memetic evolution changes the rules. Genetic engineering is already becoming commonplace, and some of the major inherited diseases may soon be defeated by simply removing the genes that cause them. Cloning
of sheep and other large animals is also possible and, combined with the creation of headless and brainless clones, raises the prospect of maintaining genetically identical spare parts for rich people to ensure that they always have a heart or liver ready if they need one. Other predictions for the future of ‘reprogenetics’ include babies born with the genes from two mothers, the insertion of genes for AIDS resistance into embryos, or the creation of whole suites of synthetic genes to provide designer embryos for people rich enough to afford them (Silver 1998).
Note that I said ‘the memes are busy devising’. This translates into the more accurate statement that memes for DNA testing, sequencing the human genome, and genetic engineering are successfully replicating in today’s world. Why? Because many memetic factors come together to make them successful. Enough people are sufficiently well educated; there are laboratories full of the necessary equipment; there are clever people around who manage to combine the existing memes and come up with new inventions; there is sufficient wealth to educate and fund those people to do it – and, of course, there is the human desire to have healthy, happy and successful children, and human greed that will always want more and better food, and promises of a better and easier life.
So are we just unalterably selfish creatures, driven by the competing forces of two replicators to live lives of mindless greed? Not at all. Rather surprisingly one of the consequences of memetic evolution is that humans can be
more
altruistic than their genes alone would dictate.
CHAPTER 12
A memetic theory of altruism
Altruism in the service of the genes
Once one of the greatest mysteries for sociobiology – and now probably one of its greatest successes – is the problem of altruism.
Altruism is defined as behaviour that benefits another creature at the expense of the one carrying it out. In other words, altruism means doing something that costs time, effort, or resources, for the sake of someone else. This might mean providing food for another animal, giving a warning signal to protect others while putting yourself at risk, or fighting an enemy to save another animal from harm. Examples abound in nature, from the social insects whose lives revolve around the good of their community to rabbits that thump warnings of approaching footsteps, and vampire bats that share meals of blood. Humans are uniquely cooperative and spend a great deal of their time doing things that benefit others as well as themselves: what psychologists sometimes refer to as ‘prosocial behaviour’. They have moral sensibilities and a strong sense of right and wrong. They are altruists.
Altruism is a problem for many social psychologists and economists who assume that humans rationally pursue their own interests. It is also a problem for Darwinism, although it was not always seen that way. The problem varies according to the level at which you think selection takes place – or, putting it another way – what you think evolution is for. If you believe, as many early Darwinians did, that evolution ultimately proceeds for the good of the individual, then why should any individual behave in such a way as to incur serious costs to itself while benefiting someone else? All individuals ought to be out for themselves alone, and nature ought truly to be ‘red in tooth and claw’. Yet clearly it is not. Many animals live social and cooperative lives, parents lavish devotion on their offspring, and many mammals spend hours of every day grooming their friends and neighbours. Why do they do it?
An answer that does not work is what the British philosopher Helena
Cronin (1991) calls ‘greater–goodism’ – the view that evolution proceeds for the good of the group or the species. Greater–goodism permeated biological thinking in the early part of the twentieth century and is still a popular way of misunderstanding evolution. On this view selection works ‘for the survival of the species’ or ‘for the good of humankind’. The reason this cannot work is simple. Think about the chance of infiltrators. Let us suppose there were a species of wild dog in which each dog gladly caught rabbits for every other dog, and the pack lived in amiable harmony. As long as this harmony prevailed all the dogs would benefit. But now imagine that a new dog appears that just eats all the meat he is given and never bothers to do any catching. He will, of course, get the best food, have more time to pursue the best bitches, and will generally live better. He will then, no doubt, pass on his selfishness genes to his many well–fed puppies. So much for the good of the pack – selfishness for the individual must pay.
The problems of thinking in terms of the good of the species were gradually recognised and since the early 1960s ‘group selection’ has been almost entirely abolished from neo–Darwinism (I shall consider some exceptions later). The answer that has so successfully transformed the problem of altruism is selfish gene theory. If you put the replicator at the heart of evolution and see selection as acting to the advantage of some genes rather than others, then many forms of altruism make perfect sense.
Take parental care, for example. Your own children inherit half of your genes. Your children are the only direct way your genes can be carried on into future generations and so parental care is obviously needed, but this same principle can be applied to many other kinds of altruism. Darwin hinted that ‘selection may be applied to the family’ (1859, p. 258) but did not pursue the idea any further. The British biologist J. B. S. Haldane first noted, in 1955, that a gene for selflessly jumping into a dangerous river to save a drowning child could flourish easily if that child were your own, and might still flourish, though less easily, if you saved your cousin, your niece or another more distant relative.
In 1963 a young PhD student in London, tackling on his own the unfashionable topic of altruism, had just had his first paper turned down. He became so lonely struggling with the unfamiliar mathematics involved that he sometimes used to work all evening in the main hall at Waterloo railway station just to have people around him (Hamilton 1996). But William Hamilton’s next paper, ‘The genetical evolution of social behaviour’ (1964), became a classic. He put numbers to Haldane’s suggestion and developed what has come to be known as the theory of
kin selection. He imagined a gene G that tends to cause some kind of altruistic behaviour, and explained that ‘Despite the principle of “survival of the fittest” the ultimate criterion which determines whether G will spread is not whether the behaviour is to the benefit of the behaver but whether it is to the benefit of the gene G.’ (Hamilton 1963, p. 355). This means that altruistic behaviour can spread in a population if animals are altruistic towards their own kin. The nearness of the relationship determines just how much it is worth paying for the possibility of aiding the spread of the gene. Instead of basing everything on the idea of individual fitness, the important quantity becomes ‘inclusive fitness’, which takes into account all the indirect ways in which a gene can benefit (Hamilton 1964). The mathematics can get extremely complicated in real–life situations, but the principle is simple.
Genes are invisible. A monkey that is going to share some food cannot be sure whether the other monkey is really her sister or not, and certainly cannot look inside and find out just which genes the two of them have in common. However, this does not matter for the principle to work. Monkeys that, in general, share resources with kin more than with non–kin will get more of their genes into the next generation. How they achieve this may vary, and probably involves various simple heuristics such as ‘share with another monkey you were brought up with’ or ‘share with other monkeys that look, smell, or feel like your mother’ or ‘share most with monkeys you spend most time with’. Depending on the lifestyle of the animals concerned, different heuristics will work better than others. They work not by making the monkeys calculate sums, but by giving them feelings that make them act appropriately. The same applies to us. In other words, people ‘execute evolutionary logic not via conscious calculation, but by following their feelings, which were designed as logic executers’ (Wright 1994, p. 190).
We humans love our children (most of the time) and however much we are annoyed by our brother or despise our aunt, we still find it natural and unsurprising that we give them birthday presents, send them cards, or care more about them than some person we met in the street. But the theory of kin selection explains far more of the detail of family dynamics than just that, including battles over weaning, siblings competing for their parents’ resources, and other forms of family strife as well as love.
Another success for biology has been reciprocal altruism. Darwin (1871) speculated that if a man aided his fellow–men he might expect to get aid in return. A hundred years later Robert Trivers (1971) turned this speculation into the theory of reciprocal altruism, explaining how selection might favour animals who reciprocated friendship, for example,
by sharing surplus resources in good times in the hope of help in bad times. Research has revealed that many animals do just this, but there is a catch. If you are going to pay back favours, and avoid being cheated, you must be able to recognise other individuals. Most animals cannot do this, but many primates can – as can elephants, dolphins, and even such unlikely species as vampire bats. Vampire bats have a special problem in that they are very small and can easily die if they go without a meal of blood for more than two nights in a row. Fortunately, blood meals can be much bigger than one bat really needs. So the answer is to share your blood – and keep a track on who owes what to whom.
Gratitude, friendship, sympathy, trust, indignation, and feelings of guilt and revenge have all been attributed to reciprocal altruism, as has moralistic aggression, or our tendency to get upset over unfairness. If we have evolved to share resources with other humans, but to make sure our genes benefit, then our feelings are the way evolution has equipped us to do it. On this theory not only moral sentiments, but ideas of justice and legal systems can be traced to the evolution of reciprocal altruism (Matt Ridley 1996; Wagstaff 1998; Wright 1994).