Saturday, May 13, 2006

The eyes have it: dismissing Creationism again

The so called 'irreducible complexity' of existence is one of the primary arguments that Creationists make for their imaginary friend being the architect of all that exists. "If it's complex, then God done it," is their claim. Michael Behe puts the arguments, such as it is, on behalf of the supernaturalists:
Irreducibly complex systems appear very unlikely to be produced by numerous, successive, slight modifications of prior systems, [says Behe] because any precursor that was missing a crucial part could not function. Natural selection can only choose among systems that are already working, so the existence in nature of irreducibly complex biological systems poses a powerful challenge to Darwinian theory.
It poses neither challenge nor problem to Darwin's Law of Evolution, as Darwin himself pointed out when evolution was only a theory. Said he:
If numerous gradations from a perfect and complex eye to one very imperfect and simple, each grade being useful to its possessor, can be shown to exist; if further, the eye does vary ever so slightly, and the variations be inherited, which is certainly the case; and if any variation or modification in the organ be ever useful to an animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, can hardly be considered real.
Indeed. Perceptive readers will notice that I discussed this in Part 2 of last year's three-parter on the shibboleth of Intelligent Design. For those who did notice, then as a reward you might like to see the point demonstrated in a short four-minute video presented by Swedish scientist Dan-Eric Nilsson, demonstrates one possible straightforward evolutionary path. [ Hat tip, again, to S. Hicks, Esq.]

LINKS: Unintelligent design, Part 1 - Not PC
Unintelligent design, Part 2 - Not PC
Unintelligent design, Part 3 - Not PC
The human eye is NOT irreducibly complex - YouTube

TAGS: Education Science Religion Politics-US Objectivism Philosophy

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29 Comments:

Blogger Xavier said...

The IC "argument" is to Intelligent Design what the Second Law of Thermodynamics "argument" was to earlier Creationism. It will be one of those arguments to be cringed at when the movement mutates to a new form.

5/13/2006 12:45:00 pm  
Blogger Berend de Boer said...

Who is asking us to take their word on faith? Isn't the "possible straightforward path" revealing?

Can we have one repeatable laboratory experiment where they evolve some new functionality please?

You would think that after 150 years gradualism had something to show for it. But it has been an abject failure from paleontology to biochemistry. The only thing we get is handwaving, could-be-so stories. Where's the proof?

Let your guy evolve an eye and the argument is over.

5/13/2006 01:13:00 pm  
Blogger Xavier said...

"Let your guy evolve an eye and the argument is over"

By stating that, Berend, you exhibit a remarkably profound lack of understanding of evolutionary biology.

I would recommend either "The Blind Watchmaker" or perhaps "Climbing Mount Improbable" (which specifically deals with the evolution of the eye) as a good starting point, and then come back and ask the same absurd question.

5/13/2006 08:44:00 pm  
Anonymous Robert Winefield said...

Berend...

But if you want a repeatable experiment observe that one of the methods oncologists use to study multi-drug resistance in cancer is to incubate tumours in petri-dishes infused with the drug they study.

After a while (about 6-12 months) you have a population of cancer cells that are resistant to the drug of interest - thanks to your unnatural selection of random mutations.

If you want to study evolution, study microbiology - much easier to observe the progress of 1,000 generations worth of change in a petri dish than it is in a wild-life preserve.

5/14/2006 03:47:00 pm  
Blogger Berend de Boer said...

robert, you're referring to deleterious mutations. That's quite different. And exactly the opposite evolution needs.

xavier: the blind watchmaker hasn't a clue how the eye actually works.

5/15/2006 01:30:00 pm  
Blogger Andrew said...

Berend, I am going to stick my neck out here and hazard a guess; given that you think evolutionary theory is a load of gobble-de-gook and hogwash, I assume you prefer intelligent design. If this is true, I then find it strange that you call for proof (I think you meant evidence, but I won't get into that).

There is plenty of evidence suggesting that evolution occurs. There is no evidence for intelligent design. Just because something is difficult to understand or even impossible to explain, doesn't mean a super-being did it. That’s just a cop-out. I once overheard a lecturer trying to explain some simple statistical procedures to a student, and after 30 minutes he gave up and finished with the words, “just pretend it’s magic”. To that student it might have looked like magic, but it wasn’t, and magic didn’t actually explain it.

Oh, and suggesting that the results of evolution can be replicated in the lab is just bizarre. That's ridiculous. You can't replicate last week's lotto results in the lab, but that doesn't mean God picked the numbers.

5/15/2006 04:48:00 pm  
Blogger Michael said...

I wish Christians would get off their high-horse - there is no proof of 'intelligent design' because it would prove there is a God.

And with proof, there is no faith.

"You believe because you have seen. Happy are those who have not seen and believe." - Jesus Christ, berating Thomas for not having faith in the Resurrection until he saw and touched Jesus.

I do apologise if this turns into an anti-Christian thread - it was my idea to present a Christian view on why IC is flawed.

5/15/2006 08:03:00 pm  
Blogger Berend de Boer said...

Andrew, evolution is a catch-all word. You have to define your terms properly.

Let me do that for you.

Evolution as natural selection. We call it reshuffling of existing functionality/genes. It occurs. Darwin was a genius for detecting this.

Next we have deleterious mutations, loss of functionality. Can lead to evolutionary advantage. Famous example is the ice bear.

And lastly we have the supposed creation of new functionality. No proof. No laboratory experiments. Just have faith. Not enough if you're a scientific realist.

I'm sure it upsets lots of people who define science as what scientists do, but that doesn't do it for me and people who want to make a careful distinction between science and non-science. I also don't believe in black matter, quarks and aliens for example. Ockham's razor and all such.

And it is no bizarre if we ask for proof in the lab? You're making my point Andrew. Evolutionism is just like faith. You never have to show how new functionality can arrive, how gradualism possibly can work. Just believe.

I'm not sure if ID can be called science. It is falsifiable (i.e. showing that a some system with a high enough irreducibly complex quotient does exist is enough), but in this case falsifiability isn't enough for me. And it leaves you open to claims as "this is by design" while perhaps there is a way to evolve it (the whole argument from ignorance). But I need to read the books actually, I admit I'm not as well versed in ID as I would like to be.

5/16/2006 06:52:00 am  
Blogger Berend de Boer said...

Michael, Christians are not happy with ID. ID works if an alien race created live on earth. It leaves the whole question of the designer open.

5/16/2006 06:54:00 am  
Blogger Bernard Darnton said...

Nobody should be happy with ID because it's completely empty. If we're irreducibly complex and therefore must have been created by, let's say, "aliens" then the aliens will be irreducibly complex. Who made them? Presumably some other irreducibly complex "other aliens". It's just a complicated way of saying, "I have no idea and I can't be bothered trying to work it out." Or a Trojan horse for God. Hmmm...

5/16/2006 05:30:00 pm  
Blogger Berend de Boer said...

Bernard, but on the other hand: is it possible, in principle, to determine if something has been designed or has evolved?

I've asked PC if he thought that it was possible to proof that a 737 was designed. Is it possible to decide between these two? That's an interesting question which PC has yet to ponder I'm afraid.

Saying something has evolved, but giving neither mechanism nor proof is also "can't be bothered to work it out." Not necessary of course, because as everyone knows, evolution is true. Everyone agrees!

5/16/2006 07:55:00 pm  
Blogger Bernard Darnton said...

We have the mechanism - self-replication, random mutation, natural selection, and lots of generations.

We can discount evolution as the origin of a 737 because it doesn't contain its own blueprints or the machinery required to create new 737s. It cannot self-replicate and therefore none of the evolutionary mechanisms are there. That means that the 737 must either have been designed and built by something else or be the result of some random aggregation. Knowing nothing of the 737s history I would guess at design because the whirlwind-in-a-junkyard proposition is too unlikely.

The mistake of "intelligent design" is to confuse the complexity of a designed artifact (eg an aircraft), which must be generated all at once, with the accumulated complexity of an organism. The entire point of evolution is that complexity is not irreducible - it is accumulated over vast spans of time via the mechanism given above.

Given the vast amounts of time required, it is ludicrous to demand that the experiment is rerun. You need to look for other ways of testing the theory. Can the proposed mechanism be shown? What predictions does it make? Does it stack up better than "my invisible friend did it"? :-)

5/17/2006 09:40:00 am  
Blogger Brian S said...

Berend - Yes, it is possible to show that a 737 was designed. In order to build a 737, you need a great deal of explanatory knowledge. On examining the aircraft you would find codes, documentation and instructions at nearly all levels you cared to examine. For example, you would find part numbers stamped on various components, wiring diagrams, and instructions manuals in the cockpit. These are symptomatic of a design process.

Intentional design requires explanatory knowledge and that in turn requires language and memes. Biological evolution on the other hand is not based on explanatory knowledge. And for that reason you would not expect to find any kind of documentation associated with something that has biologically evolved.

Having said that, the difference between intentional design and evolution is not that each produces different outcomes. Some designed objects clearly have no documention or marks on them indicating a maker. The difference is that design through explanatory knowledge is much much faster and requires only that "ideas die in our stead". So you would therefore expect an evolutionary process to generate a foosil record because actual organisms must die, not ideas. The lack of a fossil record for 737s would be another indication of intentional design.

5/17/2006 10:00:00 am  
Blogger Andrew said...

Bernard - you need to be careful when you say Knowing nothing of the 737s history I would guess at design because the whirlwind-in-a-junkyard proposition is too unlikely.

Remember that ID supporters use the very same line when arguing against evolution. I was surprised to see you write that.

5/17/2006 10:54:00 am  
Blogger Berend de Boer said...

Who wrote that it was more likely that a hurricate would run over a dump and a 737 would be result, than that live would come into being?

On the particulars: I suggest you pay more attention to biochemistry research. Everything in the cell is designed to avoid mutation. It contains many mechanisms to avoid mutation at all costs.

And on the blueprint: recently Nature published an article about a plant that can fix its own mutations, apparently without using DNA as a template.

Lolle, S.J., Victor, J.L., Young, J.M. and Pruitt, R.E., Genome-wide non-mendelian inheritance of extra-genomic information in Arabidopsis, Nature 434:505–509, 2005.

This plant has a "revert-to-saved" mechanism. So it seems to have a blueprint.

That's the problem with biochemistry. It has come up with an amazing list of tiny motors, machines, repair mechanism, mutation correction mechanisms, that doesn't seem to fit in well with gradualism.

5/17/2006 11:19:00 am  
Blogger Bernard Darnton said...

Andrew - I am very well aware that creationists use the likelihood of the hurricane in a junkyard producing an aircraft as an anti-evolution argument, which was why I immediately followed with the point contrasting the all-at-once design of the aircraft with the incrementally increasing complexity of organisms over time.

Ironically, what the hurricane in a junkyard really shows is that complex objects don't appear by magic, which, when you boil it down, is exactly what's claimed by creationists who like the argument so much.

Secondarily, it shows that design by intelligent beings (in this case Boeing engineers) is one method of creating complex things. It nowhere suggests that this is the only method by which complex objects come into existence.

Berend - of course cells try to avoid mutation and repair themselves. Mutation is almost entirely bad and will often kill a cell. But that doesn't mean it doesn't ever happen and it doesn't mean it's always bad. Occasionally something happens which confers a slight advantage on an organism or its offspring and that change is passed on.

There are a huge range of machines, both at the cellular and the organism level but that doesn't mean they came into existence in one grand moment. Good repair mechanisms will have been preceded by mediocre repair mechanisms, which were preceeded by bad repair mechanisms and with everything in between. The point is simply that at any point in time, the slightly better repair mechanism is more likely to have been passed on than it's slightly worse cousin.

The post that started this thread illustrates this beautifully, showing that you don't have to invent a camera in one step. Hundreds of thousands of tiny steps, each an improvement on the last will lead to where we are now. A creature with a fully functioning eye is clearly different to a creature with no eyes, but each parent-child pair would have been virtually indistinguishable.

Often machines coopt bits that have previously been used for other purposes. The bones that transmit sound in your ear used to be part of your ancestors' jaw hinges. Your voicebox is made of cartilage that your ancestors used to support their gills. Odd design but classic evolutionary, incrementalist, scavenging of anything that happens to be lying around.

One thing not illustrated by that video is how things can travel in various directions. In the video the skin becomes slightly concave and eventually becomes a camera eye. In some animals the changes went the other way and the skin became convex. This gives directional light sensitivity but removes the possibility of growing a lens. It is clearly inferior to our eyes but insects are stuck with them because they can't shift from convex eyes to concave eyes without going through steps that are inferior to what they have now. This looks far more like incrementalism than design.

5/17/2006 01:21:00 pm  
Blogger Berend de Boer said...

Bernard: of course cells try to avoid mutation and repair themselves. Mutation is almost entirely bad and will often kill a cell. But that doesn't mean it doesn't ever happen and it doesn't mean it's always bad.

Bernard, that's exactly the point. Your functionality enhancing mutation hasn't been observed ever. Proof please, handwaving and just-so stories don't do it for me when we're talking about science.

5/17/2006 02:22:00 pm  
Blogger Berend de Boer said...

I just watched the video, and as I feared, this is such an incredibly stupid simplifcation that if this is what passes for debate and argument on the evolutionist side, whatever other side has already won. Shameful.

5/17/2006 02:30:00 pm  
Blogger Berend de Boer said...

It seems this short video is from a PBS series. Random link which sums up the criticism:

Nilsson's interesting presentation is periodically interrupted by more pictures of animals, this time showing presumably intermediary forms--including a flatworm with a simple cup eye, a chambered nautilus with a pin-hole camera eye, and some vertebrates. But no biologist believes that chambered nautiluses evolved into vertebrates, so it's not clear what relevance these forms have to the argument. Nevertheless, Nilsson concludes: "And that is really exactly the way eye evolution must proceed."

Nilsson's hypothesis, however, requires a pre-existing layer of light-sensing cells, and these require the simultaneous presence of several extremely complex and specialized molecules. According to Darwin's theory, such a complex molecular apparatus must have formed as a result of innumerable small steps, but no one knows how this could have happened. The origin of the light-sensitive cells that Nilsson needs for his hypothesis remains a mystery.

Furthermore, in order for evolution to work, variations must be heritable--that is, they must be passed on to subsequent generations. There is no known mechanism by which real organisms could generate the variations envisioned by Nilsson, much less pass them on to subsequent generations. So Nilsson's mechanism--plausible though it may seem--has no counterpart in living things.


http://www.reviewevolution.com/viewersGuide/Evolution_01.php

(Guys don't attach the messenger, haven't looked at this website at all, have never seen it, but the arguments are ok).

5/17/2006 02:38:00 pm  
Anonymous Robert Winefield said...

"robert, you're referring to deleterious mutations..."

Bollocks. In a petri-dish you can select for deletorious or useful "gain of function" mutations. I've done it - selecting for bacteria that grow in the presence of nitrophenols. The other bacteria weren't killed, they just couldn't grow very fast.

5/17/2006 02:39:00 pm  
Blogger Berend de Boer said...

Here a little bit of how an eye actually works:

‘When light first strikes the retina a photon interacts with a molecule called 11-cis-retinal, which rearranges within picoseconds to trans-retinal. (A picosecond [10-12 sec] is about the time it takes light to travel the breadth of a single human hair.) The change in the shape of the retinal molecule forces a change in the shape of the protein, rhodopsin, to which the retinal is tightly bound. The protein’s metamorphosis alters its behavior. Now called metarhodopsin II, the protein sticks to another protein, called transducin. Before bumping into metarhodopsin II, transducin had tightly bound a small molecule called GDP. But when transducin interacts with metarhodopsin II, the GDP falls off, and a molecule called GTP binds to transducin. (GTP is closely related to, but different from, GDP.)

‘GTP-transducin-metarhodopsin II now binds to a protein called phosphodiesterase, located in the inner membrane of the cell. When attached to metarhodopsin II and its entourage, the phosphodiesterase acquires the chemical ability to “cut” a molecule called cGMP (a chemical relative of both GDP and GTP). Initially there are a lot of cGMP molecules in the cell, but the phosphodiesterase lowers its concentration, just as a pulled plug lowers the water level in a bathtub.’


Now view the handwaving of Nilsson again.

5/17/2006 03:02:00 pm  
Blogger Josh said...

"But no biologist believes that chambered nautiluses evolved into vertebrates, so it's not clear what relevance these forms have to the argument."

Quote from the original post:

"...because any precursor that was missing a crucial part could not function."

The relevance of these forms is that they show that it is possible to have a functioning eye that doesn't have all of the "crucial parts" of the human eye.

I haven't taken the time to read/watch through all of this, but as I understand it, what we have is not a defence of evolution, but a refutation of irreducible complexity. IC claims that certain features could not have evolved in principle - to refute that you don't need to supply a real example, all you need is a "story" that shows that it's possible that such a feature could have evolved.

Regarding "functionality enhancing mutations", see:

http://talkorigins.org/indexcc/CB/CB101_2.html

5/17/2006 03:46:00 pm  
Blogger Berend de Boer said...

Thanks to the internet I found much more on this eye evolution stuff from Nilsson. We have the "A Scientific Scandal" article by David Berlinksi which appeared in the April 2003 issue of Commentary Magazine: http://www.discovery.org/scripts/viewDB/?command=view&id=1408

Quote: In my essay, I suggested that Nilsson and Pelger's arguments are trivial and their conclusions unsubstantiated. I also claimed that representations of their paper by the scientific community have involved a serious, indeed a flagrant, distortion of their work.

NILSSON AND Pelger's work is a critic's smorgasbord. Questions are free and there are second helpings.

I think the Discovery website is a Creationist website? But the Commentary Magazine didn't offer these articles for download, except to paying subscribers.

We also have a response by Dan Nilsson: http://www.discovery.org/scripts/viewDB/index.php?command=view&id=1509

Contrary to Mr. Berlinski’s claim, we calculate the spatial resolution (visual acuity) for all parts of our eye-evolution sequence, and the results are displayed in figure 1 of our paper. The underlying theory is explained in the main text, including the important equation 1 and a reference to Warrant & McIntyre (1993), where this theory is derived. Yet Mr. Berlinski insists that “Nilsson and Pelger do not calculate the visual acuity of any structure.” It would be much simpler for Mr. Berlinski if he went just a tiny step farther and denied the existence of our paper altogether.

To which Berlinksi responds again:

n fact, no underlying theory whatsoever is explained in Nilsson and Pelger’s main text, or in the legend to figure 1; and while they do assert that calculations were made, they do not say where they were made or how they were carried out. The burden of Mr. Nilsson’s denials is conveyed entirely by equation 1 and by his references.

Mr. Berlinski seems to be an evolutionist: No one doubts that the eye has evolved. Not me, in any event. Fish have eyes; rocks do not. Those eyes came from somewhere—right?—and if coming from somewhere counts as evolution, count me among its champions. No one doubts, furthermore, that the “eye could have evolved in 350,000 generations.” As I remarked earlier, the eye could have evolved in a weekend. The issue is whether it could have evolved in 350,000 generations given the constraints of random variation and natural selection.

5/17/2006 04:01:00 pm  
Blogger Berend de Boer said...

Robert, your experiment where you claim you actually evolved new functionality has too little details for me to comment on. Care to give a pointer to a published article or enhance it a bit?

5/17/2006 04:39:00 pm  
Blogger Bernard Darnton said...

Vision is very well understood and undoubtedly complex. The point is that the complexity doesn't have to appear all at once. Nilsson's description is necessarily simple because he's describing hundreds of millions of years of development in four minutes.

The Nautilus-evolving-into-a-vertebrate argument is a straw man. Of course nobody believes that. The relevance is that intermediate forms are possible. The eye doesn't have to pop into existence by magic.

The "light sensitive cells" that we started with are easy. All cells are transparent bags of stuff and if the behaviour of any of that "stuff" can be affected by light you have light sensitive cells. All of your skin is light sensitive to some degree. Plant leaves are light sensitive. That's all you need to start off with. Think small changes - you don't need to start with a fully developed retina that's appeared from nowhere. The whole point is that it isn't magic.

The point about heritability is just daft. Your body is built from scratch under instruction from your genes. If the genes that control body construction change then of course that change will be passed on if the organism reproduces.

The description of vision you've given is that for one animal. Look at its relatives and you'll find that vision works slightly differently in each. Different but similar molecules derived from different but similar genes, giving slightly better or worse vision in each case, which itself is suggestive of evolution from a common ancestor.

Humans have excellent trichromatic vision. Most monkeys have dichromatic colour vision, like some colour-blind humans. Looking at the small number of genes involved it's easy to get from a dichromatic common ancestor to modern dichromatic monkeys and trichromatic apes in simple genetic steps. A similar exercise could be done to see how a completely colour-blind nocturnal mammal ancestor gave rise to the various types of mammal vision in evidence today. By accumulating changes over 100 million years you'll get more dramatic changes than by accumulating changes over 10 million years. By accumulating over 500 million or a billion you can make quite spectacular changes.

5/17/2006 04:40:00 pm  
Blogger Berend de Boer said...

Bernard, you make a nice just-so story, but that doesn't make it science. That's the point I try to make.

It could have happened such, it could have happend so. It could, couldn't it? Well, an alien race could have created the eye, couldn't it?

I also note that Nilsson doesn't claim hundreds of millions of years, but half a million. A ridiculous claim according to Berlinski.

But with gradualism science doesn't matter. Stories are all that count.

5/17/2006 09:42:00 pm  
Blogger Bernard Darnton said...

This comment has been removed by a blog administrator.

5/18/2006 06:55:00 am  
Blogger Bernard Darnton said...

Number of times genes have been seen changing: Millions.

Number of known mechanisms for genetic mutation: Loads.

Number of plants or animals whose bodily structures have been observed changing over time through selection: Many.

Number of aliens observed doing anything, let alone creating new lifeforms: Let's see.

Remind me who's making up stories...

Tell me: when are these aliens supposed to have been here doing their handiwork? A billion years ago? Last week? And where are they now? And who made these aliens? I assume that to make all these cool things that they're irreducibly clever little buggers.

5/18/2006 07:41:00 am  
Blogger Berend de Boer said...

It's not about changing genes. Deleterious mutations are real. Reshuffling of existing material is real.

What we haven't seen is increase in functionality. Given the incredibly complex biomachinery to do even the simplest things, one can have severe doubts about this ever happening through mutation.

5/18/2006 10:30:00 am  

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