In
The Origin of Species, having laid the foundations for his theory of natural selection, Charles Darwin performs a spectacular inversion as he introduces that new term. Rather than continuing to build up an evolutionary edifice, he wonders how it could ever have been otherwise:
If during the long course of ages and under varying conditions of life, organic beings vary at all in the several parts of their organisation, and I think this cannot be disputed; if there be, owing to the high geometrical powers of increase of each species, at some age, season, or year, a severe struggle for life, and this certainly cannot be disputed; then, considering the infinite complexity of the relations of all organic beings to each other and to their conditions of existence, causing an infinite diversity in structure, constitution, and habits, to be advantageous to them, I think it would be a most extraordinary fact if no variation ever had occurred useful to each being's own welfare, in the same way as so many variations have occurred useful to man. But if variations useful to any organic being do occur, assuredly individuals thus characterised will have the best chance of being preserved in the struggle for life; and from the strong principle of inheritance they will tend to produce offspring similarly characterised. This principle of preservation, I have called, for the sake of brevity,
Natural Selection.
In my own, muted way, I feel I have undergone a similar process of reversal. Not only do I know evolution to be the only valid theory of natural history, I cannot conceptualise any feasible alternative.
Darwin's Galapagos finches have become mythical creatures which according to popular lore provided him with the crucial evidence for natural selection. In fact, Darwin collected the various finches on a whim, and failed to keep his usual meticulous catalogue of which island each came from. It was
John Gould who ultimately reconstructed the evidence, demonstrating that the variously shaped beaks were adapted for islands predominant with food sources of nuts or insects. For Darwin, it was not finches but pigeons which provided the empirical foundation for his thinking about variation; indeed, Darwin became something of an anorak with respect to them:
Believing that it is always best to study some special group, I have, after
deliberation, taken up domestic pigeons. I have kept every breed which I
could purchase or obtain, and have been most kindly favoured with skins
from several quarters of the world, more especially by the Hon. W. Elliot
from India, and by the Hon. C. Murray from Persia. Many treatises in
different languages have been published on pigeons, and some of them are
very important, as being of considerable antiquity. I have associated with
several eminent fanciers, and have been permitted to join two of the London
Pigeon Clubs. The diversity of the breeds is something astonishing. (Origin of Species, Chapter 1)
For myself, though, researching a thesis chapter on the advent of modern biology, it has been chaffinches rather than pigeons which have taken the stage in my evolutionary theorising. Looking at those garden birds out of our kitchen window (whilst chasing Darwin's beloved pigeons away from the feeders) I realise how inconceivable now it is that life could work through any mechanism other than the undesigned evolutionary one.
The earth has existed for 4.5 billion years, of which life has been around for about 4 (give or take a few million) and multicellular organisms for 1 billion. The
age of the earth is an empirical fact based on radiometric dating , one which no data of the last hundred years has disproved (though data out yesterday revealed that the
Earth's diameter has shrunk by a whole five millimetres, indicating how powerful are the instruments of modern geoscience). Yet even for the 10 000 years that young-earth creationists believe the world to have existed, their arguments propose that the same template of finch pecked at the grass of Eden the way mine do today, a mere ruffle of a feather of change between Adam's birds and my own. Watching my window over the course of a year, seeing young chaffinches arrive in Spring, and the old, tattered white-winged crow appearing no more in winter, this static view of creation seems grotesque, utterly unnatural. Leave an apple on the table, and it goes brown before your eyes, and wait a few weeks, and it begins to rot under the power of invisible bacteria; seasons change, and I know the sun gets weaker in winter, though I cannot see it having moved further away; seeds from our bird feeders occasionally drift on the wind, and where they land, seedlings emerge from the soil.
I have always trusted Darwinian as opposed to religious accounts of creation, and as I have gradually come to understand the former I have heard no evidence to fundamentally challenge that trust. But I realised today how unalterably impossible it will be for me ever to look realistically at the finch as an alien of intelligent design in a world of flux and dispassionate change. Darwinism has become, for me, a kind of belief, as something I know but cannot finally prove; crucially, however, I cannot prove it no because the data is not there, but because the evidence for it is so vast and cannot reasonably be encompassed by a single human mind. The best view on Darwinian evolution I can obtain is looking through my kitchen window. And if I say looking at the finches I believe evolution rather than creationism, this is because the former is so much more in harmony with the tunes and rhythms of the nature I can see and understand in action all around me.
Labels: creationism, Darwinism, evolution, Science and Culture
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