Article in The Telegraph Wednesday May 10th, 1995
Article Adapted from River Out of Eden
CHARLES DARWIN lost his faith with the help of a wasp. "I
cannot persuade myself," Darwin wrote, ---that a beneficent and omnipotent
God would have designedly created the Ichneumonidae with the express intention
of their feeding within the living bodies of caterpillars." Actually, Darwin's
gradual loss of faith, which he downplayed for fear of upsetting his devout
wife Emma, had more complex causes.
His reference to the Ichneumonidae was aphoristic. The macabre habits to
which he referred are shared by their cousins the digger wasps. A female
digger wasp not only lays her egg in a caterpillar (or grasshopper or bee)
so that her larva can feed on it. According to Fabre she also carefully guides
her sting into each ganglion of the prey's central nervous system so as to
paralyse it but not kill it. This way, the meat keeps fresh.
It is not known whether the paralysis acts as a general anaesthetic, or if
it is like curare in just freezing the victim's ability to move. If the latter,
the prey might be aware of being eaten alive from inside, but unable to move
a muscle to do anything about it. This sounds savagely cruel but nature is
not cruel, only pitilessly indifferent. This is one of the hardest lessons
for humans to learn. We cannot accept that things might be neither good nor
evil, neither cruel nor kind, but simply indifferent to all suffering, lacking
all purpose.
The river of my new book's title is a river of DNA and it flows through time,
not space. DNA is the hereditary chemical that characterises every living
thing by carrying its genetic specifications. This is a river of information
not of bones and tissues: a river of abstract instructions for building bodies,
not a river of solid bodies themselves. The information passes through bodies,
and affects them, but it is not affected by them on its way through.
Instead of a river of genes, we could equally well speak of a band of good
companions marching through geological time. All the genes of one breeding
population are, in the long run, companions of each other. In the short run
they sit in individual bodies and are temporarily more intimate companions
of the other genes that share a body. Genes are the smallest unit of heredity
and they survive down the ages only if they are good at building bodies that
are good at living and reproducing in the particular wav of life chosen by
the species.
But there is more to it than this. To be good at surviving, a gene must be
good at working together with the other genes in the same species - the same
river. To survive in the long run, a gene must be a good companion. It must
do well in the company of, or against the background of, the other genes
in the same river. Genes of another species are in a different river. They
do not have to get on well together: not in the same sense, anyway, for they
do not have to share the same bodies.
The feature that defines a species is that all members of any one species
have the same river of genes flowing through them, and all the genes in a
species have to be prepared to be good companions of one another. A new species
comes into existence when an existing species divides into two. The river
of genes forks in time.
From a gene's point of view, speciation, the origin of new species, is the
long goodbye. After a brief period of partial separation, the two rivers
go their separate ways forever, or until one or other dries extinct into
the sand. Secure within the banks of either river, the water is mixed and
remixed by sexual recombination. But water never leaps its banks to contaminate
the other river.
After a species has divided, the two sets of genes are no longer companions.
They no longer meet in the same bodies and they are no longer required to
get on well together. There is no longer any intercourse between them - and
intercourse here means literally sexual intercourse between their temporary
vehicles, their bodies.
When we think of the divide that leads to all the mammals, as opposed to,
say, the stream that led to the grey squirrel, it is tempting to imagine
something on a grand Mississippi/Missouri scale. The mammal branch we are
talking about is, after all, destined to branch and branch and branch again
until it produces all the mammals from pigmy shrew to elephant, from moles
underground to monkeys atop the canopy.
The mammal branch of the river is destined to feed so many thousands of important
trunk waterways, how could it be other than a massive, rolling torrent? But
of course this feeling is wrong. When the ancestors of all the modern mammals
broke away from those that are not mammals, the event would have seemed no
more momentous than any other speciation. It would have gone unremarked by
any naturalist who happened to be around at the time. The new branch of the
river of genes would have been a trickle, inhabiting a species of little
nocturnal creature no more different from its non-mammalian cousins than
a red squirrel is different from a grey.
It is only with hindsight that we see the ancestral mammal as a mammal at
all. In those days it would have been just another species of mammal-like
reptile, not markedly different from perhaps a dozen other small, snouty,
insectivorous morsels of dinosaur-food.
Natural selection is concerned only with the narrow present - with the survival
of DNA through millions of successive present moments, strung out along millions
of branches of the river of DNA. Natural selection is as indifferent to the
distant future of the race as it is indifferent to the suffering of the individuals
being selected. For, to return to our pessimistic beginning, when the utility
function - that which is being maximised - is DNA survival, this is not a
recipe for happiness.
If nature were kind, she would at least make the minor concession of anaesthetising
caterpillars before they are eaten alive from within. But nature is neither
kind nor unkind. She is neither against suffering, nor for it. Nature is
not interested in suffering one way or the other unless it affects the survival
of DNA.
It is easy to imagine a. gene that, say, tranquillises gazelles when they
are about to suffer a killing bite. Would such a gene be favoured by natural
selection? Not unless the act of tranquillising a gazelle improved that gene's
chances of being propagated into future generations. It is hard to see why
this should be so and we may therefore guess that gazelles suffer horrible
pain and fear when they are pursued to the death - as most of them eventually
are.
The total amount of suffering per year in the natural world is beyond all
decent contemplation. During the minute that it takes me to compose this
sentence, thousands of animals are being eaten alive, others are running
for their lives, whimpering with fear, others are being slowly devoured from
within by rasping parasites, thousands of all kinds are dying of starvation,
thirst and disease. It must be so.
If there is ever a time of plenty, this very fact will automatically lead
to an increase in population until the natural state of starvation and misery
is restored. Theologians worry away at the *'Problem of Evil" and a related
Problem of Suffering. On the day that 1 originally wrote this paragraph,
the newspapers were filled with one of those heartrending disasters, the
tragic crash of a busload of children.
Not for the first time, clerics were in paroxysms over the theological question,
in the words of The Sunday Telegraph, ---How can you believe in a loving,
all-powerful God who allows such a tragedy?"
The paper went on to quote one priest: "The simple answer is that we do not
know why there should be a God who lets these awful things happen. But the
horror of the crash, to a Christian, confirms the fact that we live in a
world of real values: positive and negative. If the universe was just electrons,
there would be no problem of evil or suffering.
On the contrary, if the universe were just electrons and selfish genes, meaningless
tragedies are exactly what we should expect, along with equally meaningless
good fortune. Such a universe would be neither evil nor good in intention.
It would manifest no intentions of any kind.
In a universe of blind physical forces and genetic replication, some people
are going to get hurt, other people are going to get lucky, and you won't
find any rhyme or reason in it, or any justice. The universe that we observe
has precisely the properties we should expect if there is, at bottom, no
design, no purpose, no evil and no good, nothing but blind, pitiless indifference.
As that unhappy poet A E Housman put it:
For Nature, heartless, witless
Nature
Will neither know nor care.
DNA neither knows nor cares. DNA just is. And we dance to its music.
F I Adapted by Dr Dawkins from his book,
River Out of Eden, published on May 18
by Weidenfeld & Nicolswi at £9.99.
c 1995 by Richard Dawkins.
