Wednesday, December 12, 2007

Ignore that nasty Mr Darwin and he might just go away ...

Okay ... time to be controversial. I am going to deal with the subject of evolution. And, in particular, the worrying trend towards Creationism that is growing in some big, important and (you would have thought) open-minded countries. I don't mean to be controversial. As far as I'm concerned, all I'm actually doing is putting across my personal viewpoint and the evidence that supports it. If it offends anyone, it is not intentional. All I will say is that if you are offended, it will have more to do with your beliefs than mine. You have been warned.

Back in 2004, I was walking through Marylebone train station when the magazine cover above caught my eye. I simply had to buy it. National Geographic magazine is an institution; a shining beacon of reporting excellence and the fact that they were obviously tackling such a loaded question intrigued me. Had some new evidence come to light to disprove Darwin's theories? Had National Geographic fallen to the Creationist lobby? I bought the magazine and was delighted to open it to the appropriate page and see this:

Yes, the cover was deliberately provocative. And yes, it made me (and probably many others) pick it up and buy it. Or, at the very least, thumb through it. But I'm glad it did. As I read my copy on the train travelling home I was heartened to read David Quammen's intelligent and thorough analysis of all of the evidence to date. Not once did he simply dismiss other theories as nonsense. All he did was present the facts and, overwhelmingly, they supported the notion that Darwin basically got it right: All living things are in a state of constant flux, adapting to their environments to ensure the survival of their species. Over vast periods of time, tiny subtle changes in physical forms and behaviours lead to the creation of new species - a process we can see greatly accelerated in the selective breeding programmes that have turned the humble wolf into forms as diverse as Great Danes, Chihuahas, Bulldogs and Greyhounds. And the fossil record shows us clearly that these small subtle changes have been going on for billions of years and that the living things we see about us are descended from forms that once looked quite different. We ourselves were more ape-like than we are now (we were never apes because apes evolved alongside us from a common ancestor). Before that, we were lemur-like and once, long long ago, we were something like fish. If we follow the path back to the very origins of life on this planet we find that you, me, wasps, willow trees, mackerel, eagles, dinosaurs, mushrooms, rattlesnakes, axolotls, moulds and cacti are all closely related. An almost unimaginable span of time (life is believed to have begun almost 4 billion years ago – that’s 4,000,000,000 years ago) may have allowed us to change into a staggering array of different shapes but we all sprang from the same fortuitous combination of organic molecules.

The Darwinian theory of evolution by way of natural and sexual selection is the best known and most widely accepted theory to explain the origins of life. But there is an alternative called the Idle Theory of Evolution. This theory goes away from the idea of Darwin’s savage ‘tooth and claw’ survival of the fittest and simply suggests that if populations rise and/or resources like food become scarce, life has to try harder to survive. But in times of plenty or a comfortable environment, life needs to do very little to survive. It becomes idle. Therefore populations oscillate rather than remain at a stable equilibrium. Idle Theory is built upon measures of energy, work, and power, rather than competition. But whichever version of the theory you subscribe to, you're still left with a huge pile of evidence to support them.

By contrast, the Intelligent Design theory proposes that complexity cannot have just randomly appeared. It argues that all living things were designed by God. However, this theory is lacking in evidence and relies on faith.

One common argument for Intelligent Design (ID) is the eye. The proponents of ID assert that 'the combination of nerves, sensory cells, muscles, and lens tissue in the eye could only have been 'designed' from scratch. After all, how could evolution, acting on one gene at a time, start with a sightless organism and produce an eye with so many independent parts, such as a retina, which would itself be useless without a lens, or a lens, which would be useless without a retina?' It's easy and simplistic to argue that this kind of complexity could not arise by chance. But only because we find it hard to grasp the time involved in developing such complexity. The pathway by which evolution can produce complex structures has been brilliantly explained in The Blind Watchmaker by Richard Dawkins, a biologist at Oxford University. The essence of Dawkins’s explanation is simple: Given enough time (thousands of years) and material (millions of individuals in a species), many genetic changes will occur that result in slight improvements in a system or structure such as the eye. However slight that improvement, as long as it is genuine, natural selection will favour its spread throughout the species over several generations. Little by little, one improvement at a time, the system becomes more and more complex, eventually resulting in the fully functioning, well-adapted organ that we call the eye. The retina and the lens did not have to evolve separately because they evolved together. Put like this, it's not so hard to imagine the eye evolving now is it? (Some of this paragraph was taken from an essay by Kenneth R Miller called Life's Grand Design which argues against ID.)

Besides which, there are creatures with eyes that are nowhere near as complex or as efficient as ours. Why would an intelligent designer equip them with inferior products?

Darwinian theory answers that question whereas ID doesn't. Dr Jack Cohen of the University of Warwick points to what he calls Universals and Parochials when discussing the evolution of individual features.

Universals are things that have happened more than once in evolution. Examples include bilateral symmetry, joints and limbs and Cohen's oft-quoted 'Four Fs' - flight, photosynthesis, fur and sex. These have appeared time and time again as responses to an organism's lifestyle and environment, regardless of species type; mammals have fur, bees and spiders have fur, some flightless birds - like the Kiwi - have a kind of fur, some moulds and other plants have fur. Convergent evolution is also a universal. This is where creatures living in similar environments evolve similar features despite their lack of close relationships. It's why sharks, penguins, dolphins and extinct icthyosaurs are all basically the same shape.

Parochials are 'one-offs'; things that have only developed in certain species, like knees, elbows, feathers, teeth etc. Only birds (currently) have feathers (some dinosaurs did - more proof of the transition between forms). Only mammals truly suckle their young. One human parochial is that our breathing and swallowing tubes have moved closer together as speech has evolved. Consequently, we can asphyxiate from choking on food whereas many other mammals can't. A dolphin's blowhole crosses the oesophagus, but doesn't interconnect. And a galloping horse breathes only through the nose, and its breathing is connected to its stride.

Eyes are a universal as they have developed independently across all animal species. In fact, 'camera' eyes (like we have) have evolved separately up to seven times and the compound eye up to four times. What’s more, certain proteins of the eye, called crystallins, have evolved independently 20 to 25 times. This is compelling evidence that the eye will always evolve. It’s inevitable. The structure of a fly's eye may be very different from that of a cuttlefish or that of a sheep, but they are all functional eyes. And, presumably, they all evolved because there was usable light to be exploited - albiet just one small segment of the electromagnetic spectrum. Some animals can see further than us, even into the ultraviolet frequencies. Some snakes have a kind of thermal 'eye' that allows them to perceive in infrared.

If God were an intelligent designer, why are there so many kinds of eye? And why, as one comedian pointed out, would an intelligent designer build humans with 'our recreation and pleasure areas sited so close to the waste disposal area'. Why do we have an appendix? Why does childbirth have to be so painful? These kinds of questions are best summed up by a dialogue between Evil (played by David Warner) and his assistant Robert (Derek Deadman) in Terry Gilliam's 1981 film Time Bandits:

Evil: Look how (God) spends his time ... forty-three species of parrots! Nipples for men!
Robert: Slugs.
Evil: Slugs! He created slugs! They can't hear. They can't speak. They can't operate machinery. Are we not in the hands of a lunatic?

Another of Richard Dawkins' books - The God Delusion - looks at the wider issue of religion but, while hotly controversial, all it essentially does is challenge people to think for themselves. It's worth noting that the primary return of volley came from Alister McGrath and his wife Joanna, two scientists who are also Christians. In their book The Dawkins Delusion, they attack Dawkins' own 'fundamentalist' disbelief in religion and argue that faith and belief can have a place in science. They ask us to remember people like the late science writer Stephen Jay Gould, who, though an atheist, was 'absolutely clear that the natural sciences – including evolutionary theory – were consistent with both atheism and conventional religious belief'. In other words, science and religion can go hand in hand. Dawkins may disagree but I'd say that this is a reasonably rational view and probably the most common view among the world's Christian population (and, for that matter, a number of other religions too). However, Christian fundamentalists - and by that I mean people who believe that everything contained in the Bible is a statement of fact - are quick to attack Dawkins and Darwin (and probably the McGraths too). They assert that evolution and religion are mutually incompatible but signally fail to provide a valid argument other than that the Bible is true. When asked to provide evidence of this, they cannot. Surely this cannot be a healthy viewpoint? As Derren Brown points out in his excellent book Tricks of the Mind:

'(But) to decide that the Bible is history, one must ignore the vast amount of impartial Biblical research that shows it really isn't - in other words, to decide that one's personal conviction means nore than clear evidence. We cannot value personal conviction when we are looking at to what extent the story stands up as fact. Such things must be put to one side; only evidence must be of interest. '

All of which is why I worry about countries like the USA. In a recent survey of 34 nations to check their acceptance of evolutionary theory – Darwinian or otherwise – America came last. Worried educationalists have pointed out that a country that doesn't believe in evolution doesn't respect rational thought or the scientific process. Therefore, how can it produce the scientists and leaders it needs to face the problems of the 21st Century? As one scientist wrote, ‘There is no credible scientific challenge to the idea that all living things evolved from common ancestors, that evolution on earth has been going on for billions of years and that evolution can be and has been tested and confirmed by the methods of science.’

The Catholic Church rejects the ID movement and supports the teaching of evolution. Both Pope Pius XII in 1950 and John Paul II in 1996 have endorsed the idea that evolution and religion can coexist. The National Council of Churches is a progressive association that represents 55 million American Christians, and it opposes ID. And yet, in several states of the USA including Kansas, Nebraska, Illinois, Arizona and New Mexico, the teaching of evolution has either been banned from schools or is ‘skipped over’ by teachers in only cursory fashion. Oklahoma’s school textbooks feature a disclaimer to the effect that evolution is a theory, not fact, because ‘no one was present when life first appeared on Earth.’ No other subject in the science curriculum gets this kind of disclaimer. But the Creationist Movement seems to be gathering ground and is spreading from State to State. The question is ... why?

Religious belief does not automatically exclude the theory of evolution. (Oh, incidentally, some Creationists rejoice in the fact that evolution is just a 'theory' as if this somehow lessens the impact of the supporting evidence. It doesn't. The term 'theory' does not have the same meaning in science as it does in everyday speech. In science, a theory is 'a logically self-consistent model or framework for describing the behaviour of a related set of natural or social phenomena, supported by experimental evidence'. In other words, a scientific theory is an explanation of how and why things happen - it's not a 'guess'.) Many religious people are happy to accept the concept of evolution because they still hold the ultimate trump card i.e. evolution may be a staggeringly beautiful, complex but natural process ... but if God created the universe and everything in it then God created evolution too. So where is the clash?

The clash, it seems, comes from us having to accept our place in the natural order of things. We once thought that we were at the centre of the universe. We aren't. We once thought that we were at the centre of the solar system. We aren't. And we once thought that we were divine beings wholly separate from the rich diversity of life on this magic planet. Well, whichever origin story you choose to believe, the arrogance of suggesting that we are somehow better than or higher than other species is proving to be a lie. Intelligent creatures do not despoil their own environment. They enhance and enrich it so that it remains stable and useful and productive for our children and future generations. If a creature as lowly as an ant can contribute to the continued health of the planet while we continue to destroy it ... how can we consider ourselves divine?

Evolution is fact. Incontravertible fact. No one has 'faked' the thousands of fossil life forms we've found in the rocks. No one surely can argue that DNA exists? With Chimpanzees sharing more than 95% of our DNA, surely it's also proven that we are closely related? You cannot simply ignore evidence and hide behind dogma. While I personally am atheist, I accept the fact that faith is important to other people. I also accept that you can have faith and accept proven scientific theory as fact. What I cannot accept is blind faith and an adherence to a belief that automatically denies all evidence that 'does not fit'.

In that direction lie the Dark Ages.

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