Saturday, November 15, 2014

Matt Ridley from the UK: Ants, altruism and self sacrifice


I find it magnificent that a difference of opinion about the origin of ants between two retired evolutionary biologists, one in his eighties and one in his seventies, has made the news. On television, the Harvard biologist EO Wilson called the Oxford biologist Richard Dawkins a “journalist”, this being apparently the lowest of insults in the world of science; it was taken as such.

I know and admire both men but having read the relevant papers I think that on the substantive disagreement between them Dawkins is right. Which is just as well, I shall explain, or we would need many more poppies for the Tower of London.

Before plunging (briefly) into the arithmetic of genetic relatedness within ant colonies, let me first pose a simple question: why do people care for their children? Raising children is expensive, hard work and intermittently stressful, but most people consider it rewarding in the end. What do they mean by that?

Do they do it just to gratify themselves, selfishly seeking these rewards, thus devaluing their generosity towards the children? Hardly.

Surely it is more likely that people bear, raise and treasure their children for the same reason that rabbits, blackbirds and spiders care for their offspring — because they are descended from individuals that cared for offspring. Throughout history those people who found child rearing worth it, despite the effort, left behind more descendants than those who did not.

I went fishing at the weekend. The salmon I was fortunate enough to land (and release) is an extreme example. Although in good shape when she left my hands, she will very likely die within the next two months, exhausted by the effort and risk of reaching a stream where she can lay her eggs. Her breeding instinct is the very opposite of rewarding for herself. But it perpetuates her genes.

This is a point that most critics of Richard Dawkins’s book The Selfish Gene persist in missing: it is the selfishness of genes that drives us to be selfless. The theory that most creatures do things that help the survival of their genes specifically explains and illuminates acts of genuine generosity.

It is the very opposite of a theory that says we should be selfish, though it does say that we are likely to be selective in our generosity. (But we knew that.)

And here is where ants come in. Ants are not generally altruistic. In fact they fight ants from other colonies to the death and sometimes enslave ants of other species. Yet within a colony, worker ants raise their sisters rather than their daughters. Wilson thinks this is because the survival of the colony is the main reward that drives their altruism: a theory called “group selection”; Dawkins believes that the survival of the ants’ genes, shared by those sisters who will become future queens, is the chief cause: a theory called “kin selection”. Cut through the mathematics and insults and that’s the core disagreement.

Lots of good evidence supports Dawkins, or rather his late colleague Bill Hamilton, who originated the theory of kin selection. For instance, although the sister-rearing habit evolved in termites and naked mole-rats as well, it appeared eight separate times in ants, bees and wasps.

This group of insects has the peculiar trait that — because males are produced from unfertilised eggs — females are more similar to their sisters than their daughters so long as they share the same father. And in all eight lineages, it appears it was already the habit in ancestral species for queens to mate only once, ensuring this genetic similarity.

Wilson used to buy this argument, but now he says he has “abandoned” the theory of the selfish gene for one based on the selective survival of competing groups. That sometimes groups compete, or that individuals need to be in groups to thrive, is not in doubt. But does it happen enough for creatures to develop genetic tendencies to put the success of the group first, before their own survival?

Wilson likes to call human beings “eusocial”, a word normally used for ants, bees and termites that live in colonies where the queen does all the reproducing. But for all the “groupishness” of people, there is very little evidence that we seek to sacrifice our own opportunities to reproduce as individuals, let alone that our groups themselves multiply. On the contrary, breeding is the one thing we like to do for ourselves.

And this is why the Wilson-Dawkins disagreement is of political relevance. “Group selection” has always been portrayed as a more politically correct idea, implying that there is an evolutionary tendency to general altruism in people. Gene selection has generally seemed to be more of a right-wing idea, in which individuals are at the mercy of the harsh calculus of the genes.

Actually, this folk understanding is about as misleading as it can be. Society is not built on one-sided altruism but on mutually beneficial co-operation.

Nearly all the kind things people do in the world are done in the name of enlightened self-interest. Think of the people who sold you coffee, drove your train, even wrote your newspaper today. They were paid to do so but they did things for you (and you for them). Likewise, gene selection clearly drives the evolution of a co-operative instinct in the human breast, and not just towards close kin.

It can even drive a tendency to defend fellow members of the group if the survival of the group helps to perpetuate the genes. But group selection is a theory of competition between groups, and that is generally known by another name in human affairs. We call it war. If group selection were to work properly, war would mean the total annihilation of the enemy by the victorious group.

Richard Dawkins and EO Wilson were once on the same side, writing influential books within a year of each other in the 1970s to explain the evolution of behaviour.

Dawkins still admires Wilson but thinks he has fallen into error. It is a bit like when Charles Darwin chastised Alfred Russel Wallace in the 1880s for his insistence that “a superior intelligence has guided the development of man in a definite direction, and for a special purpose.” To which Darwin replied, chidingly, in a letter: “I hope you have not murdered too completely your own and my child”.

Matt Ridley, a member of the British House of Lords, is an acclaimed author who blogs at www.rationaloptimist.com. This article was first published the The Times. 

1 comment:

paul scott said...

We should not forget here that Matt Ridley himself is an accomplished writer on Evolutionary biology. Dawkins is readable but very strident, and his autobiography is just plain pompous.
The genius is Edward Wilson [ E.O Wilson] . Evolutionary biology became very political at Harvard in the seventies. It was not good form to say as Wilson did that genetic make up was so powerful, that the idea of sameness and equalness [ not equality ] was absurd. People like Stephen Jay Gould could not cope with Wilson, and did his best to humiliate him.
Wilson is old now, but ia a master of evolution and has a Tom sawyer background to his life.