Sunday 30 November 2008

The Idiocy Of Creationism (part 1)

For anyone wanting to earn an easy 100,000 lira, Old Earth Creationist Harun Yahya is offering a prize for the best paper on why evolution is invalid. At first I was excited because I thought that by writing a decent paper I could swindle some creationist cash and put it towards real science, but reading the entry page was a list of every fallacious argument that Creationists come up with. So instead I felt it best to debunk the frivolous claims in my own words, even if Talk.Origins counters all these arguments and more.

(1) Life cannot emerge by chance...
Firstly, evolution does not try to explain the origin of life. Evolution is a process which acts on life that is already there, it's like complaining that plate tectonics is invalidated because we don't have an adequate theory of planet formation. How life came about certainly does need an answer, but even if that answer is Goddidit the diversity of life in it's present form can only be explained by evolution.

As for abiogenesis being a matter of chance? While Einstein was wrong to say God does not play with dice, to put life down to an expression of quantum physics would be an inadequate explanation. Instead life would need to come about by a set number of steps that have to be in the realms of possibilities of what that organic matter can do. No theory of abiogenesis is down to chance, each one is a series of steps that start with but a few chemicals and a catalyst and result in replicating organisms.

As for the probability given on their site (1 in 10950,) an explanation can be found at talk.origins. There will not be one single step that will lead from inanimate matter to fully-replicating cells. It may be hundreds of steps all requiring certain conditions in which to happen. It could take thousands or millions of years for the process to take, we simply don't know. But no scientists are alleging that the first cells will look anything like modern cells we have to work with. What survives now 3.5 billion years later would look nothing like the primitive cells that would have started the process.

(2) There is not a single intermediate fossil...
This is a flat-out lie. Firstly every fossil is an intermediate form, life keeps changing generation to generation so life can be nothing but intermediates. But that's not really the point Mr Yahya is getting at, so I'll directly address the idea of transitional forms.

Each fossil is going to be it's own complete form, it's going to look like the species of which it is. But it's the relative transition of the form in regard to older fossils and younger fossils that gives us the understanding of evolution. In our own lineage, Homo Erectus is much like us but not quite. It's probable that we are descendants of Homo Erectus, just as Neanderthals were. But it's unlikely that we are descended from Neanderthals, the DNA support just isn't there. Going back further we have Homo Habilis and even before that Australopithecus. By sorting the fossils in order, we can see a pattern of transition.

An intermediate in this case would play the role of the "missing link", an intermediate between Australopithecus and Homo Sapien is Homo Erectus. Between Australopithecus and Homo Erectus is Homo Habilis. Each is their own species, but they become intermediary forms when put in context. Humans are not the only species where we have a good fossil record of the transition. The horse and the whale both have a strong fossil record supporting the gradual transition. We have intermediaries of the fish to tetrapod transition, of the reptile to mammal, of the dinosaur to bird.

(3) “Living fossils” are a response to evolutionary myths...
Evolution is not destroyed by the idea of "living fossils", all that matters is when the species first appears in the fossil record, not when it last appears. If rabbits appeared in the fossil record long before any other tetrapod, common descent would be wrong. But a 200 million year old rabbit is not a problem at all for evolution provided there are other species before it that show a transition from reptiles to mammals, and non-rabbits to rabbits.

It all comes down to a matter of selection. If a species like the Coelacanth is in a successful form, then any variation on that form may not be as advantageous and die out. It comes down to a matter of survival, so if any macroscopic mutations aren't successful then there is no reason why we should expect change. It's a shame we can't compare the DNA of a modern Coelacanth to one from 400 million years ago, because that should highlight the difference.

(4) The unimaginable information in DNA...
Again with the "it's all too complicated to be formed by chance" argument. All that's needed to show this argument to be false is to show how information can be added. And there is such a mechanism: gene duplication. There are several thousand scientific papers explaining this phenomenon (go here and search for gene duplication). Once there is a mechanism of increasing information, combined with a process of selection on said information, the size of any genome presents no problem given enough time.

(5) Organs with irreducible complexity...
Two things here come to mind: firstly irreducible complexity is not a problem for evolutionary theory, secondly the eye and wing are not irreducibly complex. The problem of irreducible complexity was solved almost a century ago, decades before it became the new calling cry of creationists. All it takes is for an additive part to become a necessary function of the system, as soon as that happens taking away that additive part would make the system non-functional.

The eye will still work if one takes away components, so it's not irreducibly complex. One can be born without lenses in their eye and still have sight in some form. Some people are born partially or wholly colour blind, yet the eye can still serve a function perfectly well. In this case it's mistaking complexity for irreducible complexity, and that is the more important question: how did the eye evolve? The answer is through a gradual set of stages, from simple light sensitive cells all the way to what we have now. Each of these stages can be seen in the animal kingdom, it's not hard to make the link from one to the other. A wing is much the same, through gradual stages wings have evolved into what they are now. The same can be said for any complex function, the gradual stages are seen throughout nature.

(6) All the variety of life on Earth appeared suddenly 530 million years ago...
Suddenly? Well on a geological timeline, suddenly sounds right. In reality the Cambrian explosion happened over a period of tens of millions of years. There is also evidence of multi cellular life going back at least 50 million years earlier, the explosion itself is not a sudden outburst of life. There is a good run-down of the gradual timeline here. Even the rapid state of emergent life as seen in the Cambrian explosion can be seen in other points of earth's history as well.

It's also important to understand that events like the Cambrian explosion are macroscopic expressions of life. Early evolution of complex creatures would have been on the microscopic level and would have simply been too small to see. Whatever events transpired to allow for macroscopic creatures doesn't mean that all phyla came to be at that point, it just means that it's the point where they are visible in the fossil record.

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