L'Ombre de l'Olivier

23 August 2006 Blog Home : August 2006 : Permalink

Evolution - Belief, Fact or what?

The statement that Cobb County, GA wanted to put on its books "Evolution is a theory, not a fact, regarding the origin of living things" is, IMO 100% correct. Evolution is a scientific theory or hypothesis and, as such, can never be proven but only disproven. However, so far, despite the efforts of the various sceptics, evolution is adopted by most scientists because it makes predictions that are testable and which, to date, have proven to be correct. Unfortunately, though, some of what it predicts has to do with the distant past and how life originated on this planet and that is where many people consider that it conflicts with their religious belief. This is also where other people accept claims about primordial evolution which border on a sort of secular religion because the fact is that we are highly unlikely to ever find proof.

What I Believe About Evolution

However, having said that, I think that it is probably true that life on earth started some 3.5-4 billion years ago and that evolution from those primitive forms of 3+ billion years ago resulted in us and all the plants and anaimals around us. I can't prove it. It is possible that God created the world in 4004 BC in a form where it looked like it had been going on for billions of years and it is possible that God created life 4 billion years ago and then interfered at various points on the path or that he simply interfered once in the beginning to get things started or... Without a time machine we will never know. Heck for all I know solipsism is correct, the world was created in 1968 when I was born and everyone else is a figment of the imagination.

So is there a God/Creator?

I reckon that Ockham's Razor implies highly limited or no intervention from a Creator but my main reason for believing that is that if not then why would God not apparently be interfering on a daly basis today? However, given what we know of quantum mechnanics and random chance, it is entirely possible that God is indeed doing this but doing it at the quantum level where we can't tell. Stick me down in the agnostic - atheist category. If God exists and intervenes, he interferes in a way which we can't tell from non-intervention.

Why do I believe evolution to be correct?

Firstly the core concept of evolution, as in survival of the fittest, is not purely a biological idea. The basic rule of economics is "Incentives Matter" and the reason for that is that humans adapt to incentives to maximise their best return from them, which is basic evolution in a non-biological setting. If you think that survival of the fittest is a lie and that things do what they will regardless of incentives then you might as well stop here. On the other hand most people who disagree with such economic theories inconsistently believe devoutly in biological evolution so we'll merely note this inconsistency in their beliefs and move on.

Secondly very few people disagree with the science of genetics, DNA and so on. Since genetics and DNA are the mechnisms that explain how we grow and how mutations and adaptations can spread this might seem to be a bit sweeping but it seems to be the case. I believe this to be because it is demonstrably working in that we can identify (for example) genetic diseases such as sickle cell anaemia and see how they come about in the population and why (malaria resistance in this case if you have one copy of the gene, anaemia if you have two). A brief note: many people wonder why diseases like sickle cell anaemia would remain in the population, the answer is quite simple. Typically they cause a long term problem but solve a shorter term one. In other words the kill you later after you have had time to reproduce whereas not having this long term disease would lay you open to some short term threat that would kill you before you have time to reproduce. It is well worth recalling that "wild" humans tend not to live much beyond 30 even after you remove the infant mortality so a progressive disease that kills you when you are 40 but protects you when you are 20 is a net gain.

Thirdly it should be noted than many evolution sceptics do accept that in-species evolution is a fact. This is because it has been observed in practise - penicillin resistance in bacteria for example and of course Darwin's famous finches. The problem is that the deniers fail to see how this can have applied to the past to such an extent that we see the enormous variety in life today.

I don't claim to have all the answers but I do believe that the fossil record and experiments with "primordial soups" make many of the steps plausible. Take, for example, the vertebrate evolution of legs from fins. Thanks to fossils like Tiktaalik and Acanthostega we have clear intermediate forms and we have some idea as to why the feet developed - in water as a "pre-adaptation" that then turn out to be useful in an amphibious environment as well and which become more useful if they adapt to being better able to take the animal's full weight. Another fascinating example of evolution are the baleen whales which are toothless, limbless sea creatures which appear to have evolved from toothed, legged land creatures. as the Tiktaalik link says, to some extent the discovery of this creature is not a surprise because evolution predicted that something like it would have existed.

Pre-adaptation is, IMO, the reason why evolution works and why living creatures also seem to carry on with less than perfectly adapted bodies. From human posture to teeth to the location of genitals (punchline to an old joke: God is a town planner - who else would route the sewage works through the playground) we have bodies that are not perfectly adapted to our life. But the reason is that the bits were originally used partly for something else and the something else was capable of being abused from it initial purpose to provide some other benefit.

The challenge to the deniers

The real challenge to those who do not believe that evolution explains the origins of life is to come up with a creature (or its attribute) which cannot be explained in terms of preadaptation and abuse. Deniers typically try the rhetorical flourish of

Evolution can't explain how the unbelievably complex evolved when things don't work without ALL of their parts. Evolution cannot explain how an eye evolved, let alone the unbelievably diverse life on this planet

and talk about how half an eye is no use. This is, to put it bluntly bogus. Firstly there are a number of plausible pathways about how eyes can develop from light sensitive skin and all sorts of different mechanisms used for seeing. The vertebrate eye is different to the insect eye is diffent to the squid/octopus eye, not to mention simple visual structures such as an ocellus. Another favourite is the implausibility of the "Cambrian explosion", but anyone who makes the most cursory examination of complexity theory can see that exponential growth of an apparently ordered limited system once a certain threshold is reached is the norm. The basic point is that once you get DNA, sex and genes working reliably then any change of the environment (caused by, for example, resource starvation because all the nice bits have already been taken) makes it likely that changes will occur and there is no reason to assume that there is only one solution to the problem of survival under new conditions. Hence speciation and hence, since the new species will then change the environment again, further incentive for more adaptations and furhter evolution into newer species, with, again, no reason to assume that a single strategy is optimum. It is critical to recall that the "Cambrian Explosion" lasted over 50 million years (or about as much time as has elapsed since the dinosaurs died out) and that the first fossil eukaryotes (i.e. non bacteria) show up in the preceding Vendian era as well.

A short fisking of Kemp

All this was inspired by Jack Kemp's recent townhall column which makes a number of highly questionable statements. I'm going to fisk the more egregious parts, although as is my wont, I'm going to start with a section that I agree with:

This "advice," which the Kansas standards quote, is: "The Conferees recognize that quality science education should prepare students to distinguish the data and testable theories of science from religious or philosophical claims that are made in the name of science. Where topics are taught that may generate controversy (such as biological evolution), the curriculum should help students to understand the full range of scientific views that exist, why such topics may generate controversy, and how scientific discoveries can profoundly affect society."

See statement at the start of this post. Evolution is a scientific hypothesis that may be disproven. It is critical that students are taught "to distinguish the data and testable theories of science from religious or philosophical claims that are made in the name of science". Unfortunately that is about as far as my agreement goes.

The newly elected school board members immediately pledged to work swiftly to restore a science curriculum that does not subject evolution to criticism. They don't want students to learn "the full range of scientific views" or that there is a "controversy" about evolution.

Criticism is not the same as denial. Evolution should be taught in a way that makes clear that it may have flaws and that it is current scientific orthodoxy, but there is no point in going further. We don't teach children the more obscure bits of relativistic theory when we do physics, we give them Newton's laws, note that Einstien and co found places where they turn out wrong and leave it at that. A similar approach to evolution in biology is all that is necessary.

Liberals see the political value to teaching evolution in school, as it makes teachers and children think they are no more special than animals. Childhood joy and ambition can turn into depression as children learn to reject that they were created in the image of God.

This is where all my sympathy for evolution sceptics dries up. The phrase WTF springs to mind, along with "I'll have some of what he's smoking" and "did he take his pills this morning?". Three questions:

why should evolution make children think they are no more special than animals?
why should this lead to depression?
and why would "liberals" want that to occur?

This is not a logical argument it is, as far as I can see, a stream of unconnected unprovable assertions.

The press is claiming that the pro-evolution victory in Kansas - where, incidentally, voter turnout was only 18 percent - was the third strike for evolution critics. In December a federal judge in Dover, Pa., prohibited the school from even mentioning intelligent design, and in February, the Ohio board of education nixed a plan to allow a modicum of critical analysis of evolution. But one strikeout does not a ballgame win. Gallup Polls have repeatedly shown that only about 10 percent of Americans believe the version of evolution commonly taught in public schools and, despite massive public school indoctrination in Darwinism, that number has not changed much in decades.

Science, sir, is not a democratic subject. You can't repeal scientific findings by legislative fiat or by opinion polls. The fact that 10% believe the version of evolution taught in public schools may be an indication that it is wrong but it looks to me more like the careful filtering of an opinion poll where various evolutionary and non evolutionary theories were presented and the majority picked evolution but split between the various options. It is I believe, entirely possible, to believe both in evolution and that God created the world and all things in it.

[...] Ann Coulter's new book, "Godless: The Church of Liberalism" (Crown Forum, $28), has enjoyed weeks on the New York Times best-seller list. Despite bitter denunciations by liberals, funny thing, there has been a thundering silence about the one-third of her book in which she deconstructs Darwinism. She calls it the cosmology of the Church of Liberalism.

Coulter's book charges that evolution is a cult religion, and described how its priests and practitioners regularly treat critics as religious heretics. The Darwinists' answer to every challenge is to accuse their opponents of, horrors, a fundamentalist belief in God.

Perhaps I should read Coulter's book and deconstruct that third. I tend to agree completely (see post yesterday) that liberals frequently act like religious fanatics but I don't think that their behaviour necessarily invalidates what they are defending. The fact that some "liberals" are unable to string together a logical argument on anything from economic policy to evolution and are forced to revert to playing the man not the ball is a sign of their stupidity. Scientists of all stripes (not to mention genetic engineers and technicians) accept the prime tenets of evolutionary theory and apply it in their work. That is the hallmark of scientific acceptability not the ravings of a lunatic fringe that grows up around it.

[...] Evolutionists are too emotionally committed to face the failure of evidence to support their faith, but they are smart enough to know that they lose whenever debate is allowed, which is why they refused the invitation to present their case at a public hearing in Kansas. But this is America, and 90 percent of the public will not remain silenced.

No we aren't. We just think that you need to come up with a testable alternative theory. If it isn't testable then it isn't science. Evolution is testable and is standing the test of time as discoveries in the fossil record and in analysis of the DNA of current species. On the other hand Creationism, Intelligent Deisgn etc. fail to make testable hypotheses and hence, since they can never be disproven, are not science but rather "religious or philosophical claims that are made in the name of science. For example if God created mankind on his own image but did not extend his own image to other creatures then why does mankind share an enormous part of its DNA with other great apes, a lesser part with other simians, a lesser part with mammals and so on? For these alternate systems to be scientific they need to explain this and nothing that I see in the bible says that God created man in his own image, chimpanzees in almost his own image, baboons in about 90% of his image etc. If humans are special then we shouldn't share so much with other species, including not just DNA but diseases and levels of cognition.

I'll close with a quote which I address to all those (Christian) religious believers who deny evolution:

I beseech you, in the bowels of Christ, think it possible you may be mistaken

I despise l'Escroc and Vile Pin