Sunday, 15 April 2007

Toying with the Truth in Science - part 5

This post continues my look at the teachers manual sent with DVDs to every UK school and college by the Creationist group Truth In Science.

Part 3 of the Learning outcomes is called; "Molecules and Mousetraps"

Understand the concept of "irreducible complexity" - that some machines are made up of many parts, all of which are necessary for function

Recognise the bacterial flagellum as an example of an irreducibly complex system

Understand that irreducibly complex structure cannot evolve by slight, successive, advantageous variations, because at certain points in their evolution they will lose function altogether

At the risk of repeating my earlier posts a little lets just pause for a moment to recognise that the entire set of "learning points" I will cover in this post share one thing in common. What they share is that neither your kids nor my kids will get asked any questions on them at all in their GCSE exams. Which does rather beg the question of why they are here at all. But we already know the answer to that don't we, so lets stick to showing you why this is a pile of bunk.

Well the first learning does itself give the full description of the concept of Irreducible Complexity itself. Irreducible complexity is an attempt to come up with an argument to prove that certain things could not possibly have evolved. Irreducible Complexity is not an accepted scientific term or concept which TiS just happen to be using in this particular case to argue a particular point. Irreducible Complexity (IC) is in fact a concoction of the Intelligent Deisgn/Creationism movement in the US.

Unfortunately IC can be a little tricky to get your head around. I have had IC used by creationists against me in discussions in a way that the developers of IC themselves did not intend. This is a fairly simple error to make for anyone unfamiliar with the ToE. In fact I have had to point this error out to several creationists. The error is illustrated by example as follows; Can an eye operate without the lens? Obviously not, er hang on there a moment, there are plenty of examples of eyes out there in the natural word which don't have lenses.

OK but alright we do kind of know what they mean don't we? Why am I being so picky with this. Let's carry on and see where we get to.

Can I operate without my heart? - No. What about my heart without one of the valves? - No. Ah now we have got the hang of it. Take an organism and slice a bit off and see it still works/lives - easy peasy - we can prove Darwin wrong in our sleep;-)

So its starting to sound a bit odd now isn't it. The reason for this and the reason why this is an error is because this is not how evolution suggests things actually do evolve - i.e. one whole part at a time - that would be a bit daft wouldn't it. There goes a creature with no eyes and wow looks it's kids have got eyes! No, that's not what evolution is at all.

The people who came up with IC in the first place did at least understand this and they did in fact intend IC to be used in just a few specific cases and not with this broad brush approach. Unfortunately most creationists know very little about evolution (many equate it with evil and so want nothing to do with it) and so readily fall into the error I have described and start asking where the first eye came from or how did a monkey give birth to a human etc. In fact I have had to point out this basic error to otherwise highly educated creationists with degree level qualifications.

So now that we have clarified the actual nature of the argument itself lets have a look at the logic and evidence and see how it stacks up.

The ToE states that nature always works with whatever is at hand but not always in the way described in the learning point i.e. with very gradual changes. Evolution can also work though the following evolutionary mechanisms; deletion of parts, addition of multiple parts; for example, duplication of much or all of a system, change of function, and the addition of a second function to a part.

(BTW if you are interested, there are some very interesting examples of organisms which appear to have evolved in this way - this is possible because certain genes appear to act to control whole suites of other genes and this means that a single mutation in a gene in a centipede which controlled all the other genes which in turn controlled the development of a body segment and pair of legs, could make an extra segment and pair of legs in one fell swoop of variation - anyway back to the point)

Given enough time this can be shown to lead to some pretty amazing changes in both the form and structure of part of an organism and the use or function of the form or structure. For one such example consider the swim bladder in fish, and lungs in animals. (BTW its interesting to note that we now think that this happened the opposite way around to that suggested by Darwin himself - there are after all, no sacred cows in science) There are many more amazing such examples.

Next we see that TiS pick out just one of these aspects of evolution. They mentioned it but do not explain it very well;

Understand that Darwinian scientists dispute this, and that the theory of co-option (Borrowing parts from other machines) is a possible solution to the problem of irreducible complexity.

So, they even grant that this could explain away their own proof, but hang on - doesn't that mean it isnt a proof after all? I mean if that is a way to explain it away then what exactly does their proof prove?

Well once again I think that TiS are being subtle and clever here. The onus is placed upon the reader/student to think for themselves whether or not co-option does explain IC away. Of course the don't give the poor thinker anywhere near a clear picture of either concepts so it is very likely that the vast majority will be left doubting very much if co-option (whatever it is exactly) can explain away IC - after all IC seemed so sensible and easy to grasp didn't it? Well before I asked you to think about it a little bit anyway.

Next they try to finish the student off with more confirmation that Co-option (whatever it is) can't explain IC;

Recognise that the needle-nose cellular pump has some similarities to the bacterial flagellum, but that it only contains 10 of the 40 protein components of the flagellum.

Wow - only 10 out of 40 - no chance.

Meanwhile, back in the real world, the evolution of the flagellum is now mapped out pretty thoroughly and yes it seems to work just fine without any miracles as far we can tell.

The full details are here.

The Creationists are presumably now looking around for the next thing to claim as Irreducibly Complex, they have after all been doing this quite a while and there are a long list of similar claims of IC subsequently shown to be false.

This page shows a bit more on this subject if you are interested.

Lets also remember the more general point that you can't use ignorance to prove something. i.e. if we can't currently explain the evolution of a particular structure this does not prove that we never will or that it was therefore designed. This simple bit of common sense actually leaves the whole IC issue dead in the water before they come up with the next IC claim anyway, if you stop to think about it for a moment.

The final learning outcomes for our kids from this section according to TiS is;

Recognise that the process by which cells assemble the flagellum is precise and complex, and has not been explained in Darwinian terms.

Well we just did didn't we.

Once again, none of this is in the syllabus and so it won't help the students pass their exams. But then we have seen by now that getting the kids through the exams is not what TiS are aiming for.

Further input on this topic from Tony Jackson in a comment on the Learning Lessons 1 entry;

Why should ‘irreducible complexity’ be taught at GCSE? Surely a science syllabus – especially at this elementary level – should reflect established (ie well-supported by the evidence) scientific theories and basic facts. Irreducible complexity fails in both of these criteria.

1)Many of the specific examples of ‘irreducible complexity’ that Michael Behe uses in his book are just plain wrong.

2)Even if there are examples in biology where some structure fits Behe’s definition, there are several well-known evolutionary mechanisms that can in principle account for their origin.

Behe wrote his book over ten years ago. That’s a very long time ago in today’s fast-paced science. It’s instructive to check up and see how the scientific community has reacted to the concept of ‘irreducible complexity’. To do this, there are a number of publicly accessible databases of the published scientific literature. Such literature searches are essential and routine tools that active scientists use all the time to follow what’s hot and to keep up with the latest discoveries. PubMed is one I use a lot. If you go there and type “irreducible complexity” you will get a grand total of papers that mention the phrase. But it’s worse than that because on closer inspection three of these papers are clearly irrelevant to Behe’s meaning and the remaining four papers are all critical of Behe.

Think about that. Even after more than ten years, it seems that there are simply no papers in the primary scientific literature that use the concept of ‘irreducible complexity’ to make predictions, to discover new insights into nature and to test hypotheses.

Contrast this state of affairs with a phenomenon called “RNA interference” (or RNAi), which was discovered at about the same time Behe wrote his book. Now on PubMed, I got 9371 hits for “RNA interference” and 8666 hits for “RNAi”.

That’s the difference between a genuine scientific discovery and an utterly bogus claim.

The next section in the TiS teachers manual is "How did life begin?" which has nothing to do with the theory of Evolution at all.

Any questions or corrections please let me know.

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