How does reducing one's ability to find a mate confer any kind of genetic advantage?
The image of the Virgin Mary is reported to have been seen on a tree stump in the village of Rathkeale, and thousands of people have flocked there. And yes, this is quite absurd.
But is it more preposterous to believe that that piece of timber, and the willow tree from which it came, and the eye that beheld the wood, arrived in this world entirely by accident? For in this, the 150th anniversary of the publication of 'The Origin of Species', that is what we've been endlessly told this year.
Before Darwinian dogmatists sneer the words "intelligent design" and "creationism", let me declare that I embrace neither concept. But nor do I reject them. I've been reading up on this subject recently, especially Ernst Mayr, Dawkins and Darwin, and what strikes me most is the sheer act of Darwinian faith which is required for us to accept that natural selection was the prime engine that conjured the vast complexity of modern life from its birthplace in the methanogenic oceans of the pre-Cambrian.
It's far too easy to look back and postulate a route to where we are today, deducing it from whatever evidence archaeologists and palaeontologists have found. Instead, we should be taking the teleological approach, and viewing the problem the other way round. How can life naturally progress forward from those evil seas to our modern world, but without having the least idea where it is going?
Now life as we know it depends on proteins. But even a relatively simple molecule such as insulin, consists of 51 conjoined amino-acids, with a molecular weight of 5808: nearly 6,000 times the weight of a hydrogen atom. And an average living cell contains 100 million protein molecules, involving perhaps 20,000 varieties of protein. Moreover, there are several hundred thousand types of protein, all of them impossibly complex. How were these made by accident? To say that such order is implicit in all of nature -- as some scientists do -- is begging the question, the equivalent of saying matter is intrinsic to materials.
Time, you might add; time will enable these molecules to be assembled, bit by bit. Indeed, given enough time, you will be able to explain everything that has occurred from the first genetic trick at the dawn of existence. But has there been enough time? Would a mathematician looking at the random ingredients of those ancient, poisonous seas be able to propose that, actuarially, enough molecular encounters would sooner or later result in the first spark of life (whatever that might be) leading to us, just four billion (or so) years later? That's not an awful lot of time, considering all the random accidents that could not merely have started proto-life, but also wiped it out.
This logically means that there must have been many competing proto-life forms. Just one -- apparently the one that depends upon DNA -- survived. But how did the dear old double helix come into existence? For DNA doesn't function at all unless complete. It's either the final, impossibly complex but useful article, or it's incomplete and utterly useless. So, no simple evolution here.
But that's the way with so much of "natural selection". It often doesn't tolerate halfway houses. The swallow that doesn't make it from Africa to Europe simply doesn't survive to reproduce its genes. That's it: line extinct. Or put it another way. I drop you and your family in an unpopulated Africa, without telling you where you are, or giving you a map or a compass, and I then tell you to find your way back to your sitting room. You couldn't do it. You'd die on the way. Your children, neither knowing your fate, nor what NOT to do, (because evolution is about numbers, not about learning) would follow, to a similar fate. And their children, also.
Granted -- with enough species types, and enough genetic mutation, sooner or later, someone will get back to the right room in Ireland, and then return to the right desert in Africa.
But is there enough of the vital dimension, TIME, to enable the right gene to emerge and triumph, out of all these ghastly accidents?
Or -- even more absurd -- did the complete navigation gene simply arrive out of nowhere?
Even the title of Darwin's book hasn't been answered adequately. How do separate species emerge, in the process of "speciation"? How do outwardly identical, but reproductively-discrete species emerge alongside one another in the same ecological niche, as many kinds of fish have done? This is counter-intuitive. For how does reducing one's ability to find a mate confer any kind of genetic advantage? Conversely, not one single species of domesticated animal is unable to mate with its remote relatives.
Human-triggered speciation has never occurred, despite separations of thousands of years. The dingo of the Australian desert is five millennia removed the Arctic wolf; yet they can still interbreed. Similarly, Northern Dancer could have bred with a Connemara.
So, is speciation naturally pre-ordained? If so, is it unreasonable to ask how, by whom and why?
And are such questions more or less absurd than ones about the stump in Rathkeale?
kmyers@independent.ie
- Kevin Myers
