Dr. James Le Fanu - Doubts About Darwin
Tags: 2008/2009Understanding Science.Dr. James Le Fanu combines medical general practice with writing a twice-weekly column for the Telegraph newspapers
Charles Darwin was a brilliant naturalist privileged to live in extraordinary times, when intrepid voyagers like himself would return from their circumnavigations around the world with their ships’ holds filled with tens of thousands of never previously described species of insects, fish, plants and mammals. This revelation of the astonishing diversity of the living world extended to the long-since extinct, for this was also the Golden Age of Geology with the discovery of the fossilised remains of vast improbable creatures that roamed the surface of the earth long before the arrival of Man.
Darwin’s pre-eminent position in the pantheon of British scientists derives from his having formulated the all-encompassing theory of ‘natural selection acting on the random mutation of genes’ to explain not just the hundreds of millions of species, in all their diversity, with which we share this planet but the much greater number of the long-since extinct, as all having evolved ‘by modification’ from a single ancestor.
What to make of this? There can be no disputing the fact of evolution. The whole history of the universe, after all, from the moment of the Big Bang onwards is an evolutionary history of the simplest forms of matter to the ever-more complex. Nor can there be any disputing the concept of ‘natural selection’ as there is nothing so self-evident than that Nature selects the strong and robust over the frail and vulnerable. Nor is there any reason to doubt that Darwin’s proposed mechanism of natural selection acting on random genetic mutation accounts, at least in part, for the subtle differences between closely related species – epitomised by the Galapagos finches with their different shaped beaks, each ‘adapted to its particular method of finding food’: one a powerful crushing nutcracker, another similar to a pair of probing tweezers, and so on.
The problem, rather, and a continuing source of scepticism, about Darwin’s evolutionary theory is that its simple mechanism explains too much – not just, as noted, the entire history of life, but there is nothing too bizarre or extraordinary about the billionfold biological complexities of the living world that cannot be explained as having evolved to be as it is over aeons of time. And that, on reflection, is a very odd thing for any theory to do for, as the philosopher Karl Popper pointed out, theories that explain everything in general end up explaining not very much in particular. Darwin’s evolutionary theory generates the illusion that we know vastly more than we really do, while its too simple explanations drain the phenomena of life of the sense of the extraordinary. And there is nothing more extraordinary than ourselves. 'Wonders are there many', wrote the Greek playwright Sophocles, 'but none so wonderful as Man'. And rightly so. We are not only (so far as we can tell) the sole witness of the splendours of the universe but uniquely capable by virtue of the power of reason and imagination of our extraordinary minds to comprehend it. For the best part of 2500 years from the philosopher Plato onwards this dual aspect of the human experience – the recognition of the wonder and beauty of the living world and the intellectual properties of the human mind – were interpreted as direct evidence of our exceptionality – that we were created Imago Dei, in the image of God.
This is scarcely the modern view. Many to be sure are moved and uplifted by the wonder of the world about us but the prevailing view is that science and particularly Darwin’s evolutionary theory, solved the fundamental questions – or as the evolutionary biologist Professor Richard Dawkins puts it 'our own existence that once presented the greatest of all mysteries, is a mystery no longer. Darwin solved it.' We, like all living things, are the fortuitous consequence of that same blind materialist process of natural selection acting on random genetic mutations – a chance life form on a minor planet lost in the vastness of space. There is indeed nothing that cannot be explained in materialist terms – the beauty and diversity of the living world in terms of the materialist genes, and the powers of the human mind in terms of the material electrochemistry of the brain.
There are, as you will know, a series of well-rehearsed arguments that challenge the explanatory power of Darwin’s theory, particularly ‘the puzzle of perfection’, how a random process could bring into existence (for example) the remarkable properties of the human eye and the many inconsistencies of the fossil record with their failure to provide the empirical evidence for gradualist evolutionary transformation.
But my purpose today is, as it were, to extend that argument by showing how, quite inadvertently, the scientific findings of the recent past have confounded the scientific materialist view and in the process reaffirmed our exceptionality.
It all goes back to the recent past of the mid-1980s when an astonishing series of scientific developments took place that held out the prospect of finally resolving the two outstanding biological problems:
the nature of ‘form’ – and why it is that the millions of species are so readily distinguishable one from another; and,
the nature of ‘mind’ – how the material working of the brain gives rise to the material thoughts, ideas and impressions of the human mind.
Those major scientific developments were, first, the ability to spell out the entire sequence of genes (the genome) strung out along the Double Helix – of worm, mouse, fly, man and many others, and thus reveal the genetic instructions by which all living things replicate their kind with such fidelity from generation to generation. And, second, sophisticated brain scanning techniques that would permit scientists for the first time to observe the brain ‘in action’ from the inside, thinking, imagining and reflecting, and in the process account for that unique character or personality that is each one of us.
The completion of the Human Genome Project in 2001 marked 'One of the most significant days in history', as one of its architects described it. 'Just as Copernicus changed our understanding of the solar system … so knowledge of the human genome would change how we see ourselves.' At the same time Professor Stephen Pinker, of the Massachusetts Institute of Technology, writing in the journal Scientific American described how neuroscientists with their new scanning techniques had investigated everything 'from mental imagery to moral sense', and confidently anticipated 'cracking the mystery of the brain'.
Nearly a decade has passed since those heady days and looking back it is possible to see how the findings of both endeavours have enormously deepened our knowledge of life and the mind – but in a way quite contrary to that anticipated. The Genome Projects were predicated on a reasonable assumption that spelling out the full complement of genes would clarify, to a greater or lesser extent, the source of that diversity of form that marks out the major categories of life. It was thus disconcerting to learn that virtually the reverse is the case with the near equivalence of a modest 20,000 genes across the vast spectrum of organismic complexity from a millimetre-long worm to ourselves. It is similarly disconcerting to learn that the same regulatory or homeotic genes that cause a fly to be a fly cause a human to be a human and that our genome is virtually interchangeable with that of our fellow vertebrates such as the mouse and our primate cousins. 'We cannot see in this why we are so different from chimpanzees', remarked the director of the Chimp Genome Project. 'The obvious differences cannot be explained by genetics alone.'
These findings were certainly unexpected, but they also undermined the central premise of biology: that the secret of the near infinite diversity of form and attributes that so definitively distinguish living things one from the other must ‘lie in the genes’. The Genome Projects were, after all, predicated on the assumption that the ‘genes for’ the delicate stooping head and pure white petals of the snowdrop would be different from the ‘genes for’ the colourful upstanding petals of the tulip, which would be different again from the ‘genes for’ flies and frogs, birds and humans. But the genome projects reveal a very different story, where the genes ‘code for’ the nuts and bolts of the cells from which all living things are made – the hormones, enzymes and proteins of the ‘chemistry of life’ – but the diverse subtlety of form, shape and colour that distinguishes snowdrops from tulips, flies from frogs and humans is nowhere to be found.
Put another way, there is not the slightest hint in the composition of the genes of fly or man to account for why the fly should have six legs, a pair of wings and the brain the size of a full stop and we should have two arms, two legs and that prodigious brain. These ‘instructions’ must be there, of course, for otherwise flies would not produce flies and humans humans. But we have moved over the last decade from assuming that we knew the principle, if not the details, of that greatest of marvels, the genetic basis of the infinite variety of life, to recognising that we not only do not understand the principles, but that we have no conception of what they might be.
We have here, as the historian of science Evelyn Fox Keller puts it:
One of those rare and wonderful moments when success teaches us humility … [W]e lulled ourselves into believing that in discovering the basis for genetic information we had found the ‘secret of life’; we were confident that if we could only decode the message and the secret of chemicals we would understand the ‘programme’ that makes an organism what it is. But now there is at least a tacit acknowledgement of how large that gap between genetic ‘information’ and biological meaning really is.
There is, of course, no reasonable explanation why the findings of these Genome Projects should have been so contrary to those anticipated but it is important to note that the appeal of the Double Helix and the reason why it has dominated biology for the last sixty years is that the simplicity and elegance of its structure held out the promise that the genetic instructions might be ‘knowable’. But, on reflection, that simplicity cannot be because it is simple but rather because it has to be simple in order to replicate the genetic instructions every time the cell divides. It must therefore, by necessity, condense within the monotonous sequence of chemicals strung out along its intertwining strands the form and attributes that so readily distinguish one form of life from another. This would seem to pose an impenetrable barrier to current understanding and presupposes rather the existence of some non-material force, as yet unknown to science, that from the moment of conception imposes the order of ‘form’ on life and holds it constant as its cells and tissues are constantly renewed.
It is a similar story with the recent findings of neuroscience. The opportunity provided by those sophisticated scanning techniques to observe the brain ‘in action’ generated many novel insights into the patterns of electrical activity of the brain that looks out on the world ‘out there’ and interprets the grammar and syntax of language, recalls past events and much else besides. But at every turn the neuroscientists found themselves completely frustrated in their attempt to get at how the brain actually works.
Right from the beginning it was clear there was simply ‘too much going on’. There could be no simple experiment that just scanned the brain of a subject when first reading, then speaking, and then listening to a single word such as ‘chair’. This should, it was anticipated, show the relevant part of the brain ‘lighting up’ – the visual cortex when reading, the speech centre when speaking and the auditory cortex when listening. But no, the brain scan showed that each separate task ‘lit up’ not just the relevant part of the brain but generated a blizzard of electrical activity across vast networks of millions of neurons – while thinking about the meaning of a word and speaking appeared to activate the brain virtually in its entirety. The brain, it seemed, must work in a way previously never really appreciated – not as an aggregate of distinct specialised parts, but as an integrated whole, with the same neuronal circuits performing many different functions.
Next it emerged that the brain, moment by moment, fragmented the sights and sounds of the world ‘out there’ into a myriad of separate components but without there being any compensating mechanism to reintegrate all those fragments back together again into that personal experience of being at the centre, moment by moment, of a coherent, ever-changing world. Reflecting on this problem, Nobel Prize Winner David Hubel of Harvard University would observe:
This abiding tendency for attributes such as form, colour and movement to be handled by separate structures in the brain immediately raises the question how all the information is finally assembled say for perceiving a bouncing red ball. It obviously must be assembled – but where and how, we have no idea.
Meanwhile the greatest perplexity of all remains unresolved – how the monotonous electrical activity of those billions of neurons in the brain ‘translate’ into the limitless range and quality of subjective experiences of our everyday lives, where every transient, fleeting moment has its own distinct, unique, intangible feel; where the cadences of a Bach cantata are so utterly different from a flash of lightning; the taste of Bourbon from the lingering memory of that first kiss.
The implications are obvious enough, that while it might be possible to know everything about the physical materiality of the brain, its ‘product’, the mind with its thoughts and ideas, impressions and emotions, would still remain unaccounted for.
This distinction between the electrochemical activity of the material brain and the non-material mind (of thoughts and ideas) as two quite different things might seem so self-evident as to be scarcely worth commenting on. But for neuroscientists the question of how the brain’s electrical activity translates into thoughts and sensations was precisely what needed explaining – and the failure to do so has come to haunt them. So, for everything that the sophisticated techniques of the brain ‘in action’ have undoubtedly achieved, nonetheless as the late John Maddox, Editor of Nature would acknowledge: 'We seem as far from understanding [the brain] as we were a century ago. Nobody understands how decisions are made or how imagination is set free'.
There is in the most recent findings of genetics and neuroscience a powerful impression that science has been looking in the wrong place, seeking to resolve questions whose answers lie somehow outside its domain. It is not just a matter of science not yet knowing all the facts; rather there is the sense that something of immense importance is ‘missing’ that might transform the bare bones of genes into the wondrous diversity of the living world and the monotonous electrical firing of the brain into the vast spectrum of sensations and ideas of the human mind.
This necessarily focuses our attention on what that potent ‘missing force’ might be. This is, however, an even more formidable question than it might appear for, along the way, those recent scientific findings have also subverted the credibility of what till recently we thought we did know about ourselves – transforming the certainty of the conventional evolutionary account of the 'Ascent of Man' into a riddle.
The major palaeontological discoveries of the last few decades, particularly the near complete skeletons of ‘Lucy’, Australopithecus afarensis, in 1974, and ‘Turkana Boy’, homo erectus, in 1984, would certainly appear to confirm the conventional account culminating in the emergence of modern man, homo sapiens, in Africa around 120,000 years ago that first created the human civilisation of Cromagnon Man in southern Europe with its astonishing artistic and technical achievements. But while it is certainly very difficult to conceive of anything other than some form of evolutionary scenario to account for these palaeontological discoveries, why, one might reasonably ask, is there not the slightest hint in the findings of the Human Genome Project that might account for those hundreds of anatomical changes necessary for that unique human attribute of standing upright that so readily distinguishes us from our primate cousins? Again, while the similarly genetically unexplained prodigious expansion of the size of the human brain is clearly a prerequisite for the uniquely human attributes of the faculty of language, reason and imagination, the explanatory gap between the physical materiality of the brain and the non-material properties of the mind would seem to defy the simplicity of the evolutionary doctrine that would maintain they are ‘nothing but’ the consequence of natural selection acting on the random mutation of genes.
The ramifications of the most recent findings of genetics and neuroscience and their implications for the validity of the conventional evolutionary account are clearly prodigious, suggesting we are on the brink of some tectonic shift in our understanding of ourselves. So it would take a much longer lecture than this to anticipate what form a tectonic shift might take but at the very least it would seem to refute unequivocally Darwin’s proposed mechanism of evolutionary transformation – with profound implications for our understanding of ourselves. We are, it would seem, not just a mystery to ourselves, but the central mystery of the universe to which we belong.
