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.
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:
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.
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