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Author Topic:   What's the problem with teaching ID?
Taq
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(1)
Message 331 of 337 (665087)
06-07-2012 6:03 PM
Reply to: Message 326 by Genomicus
06-07-2012 4:47 PM


Re: There is nothing to teach about ID other than as an example of pseudoscience.
No. See here:
http://thegenomestale.wordpress.com/...ogy-and-front-loading

Your evidence for FLH is the same as evolution. Of course we can find homologous proteins between all life. They share a common ancestor. This is Evolution 101.

From your website:

quote:
This is because front-loading requires that the first genomes have genes that would be used by later, more complex life forms.

This is the same prediction that evolution makes.

Again, you are not using the SETI model. You are claiming that intelligent signals exactly mimic naturally occuring ones.


This message is a reply to:
 Message 326 by Genomicus, posted 06-07-2012 4:47 PM Genomicus has not yet responded

  
Dr Adequate
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(1)
Message 332 of 337 (665088)
06-07-2012 6:14 PM
Reply to: Message 329 by Genomicus
06-07-2012 5:18 PM


Whimsical Design
That's not my argument. I'm simply pointing out that the FLH makes a specific prediction which non-teleological evolution does not make. And it's not a case of "the designer wanted giraffe's" any more than evolutionary predictions are like that.

But it does seem to be quite like the giraffophile designer.

In order to say that the conservation of such-and-such proteins would not be part of an evolutionary prediction, you have to suppose them to have so little use that natural selection would not conserve them. As you say, such a protein needs to be of so little use that "deleting it won't kill the organism, or even significantly reduce its fitness" --- and the significance of its contribution to fitness must in fact be so tiny that selective pressure won't prevent its deletion from becoming fixed in a population.

And yet the designer has to be so extraordinarily keen on these proteins that he wants every organism to have them, and indeed must install some sort of (as yet completely undiscovered) mechanism to prevent them from being strafed into nonsense by genetic drift.

Well, what is that but a whim that you postulate for your Designer ad hoc? It's unnecessary to his plan of having life, it's a mere preference. It's as though someone designed a car with an open fireplace to make back-seat loving more romantic. Someone might do that on a whim, but you can't predict that anyone would do it, because it's inessential to the main function of a car. The wheels are predictable, the engine, the steering mechanism; but the fireplace is just something of which we retrospectively have to say: oh, look, apparently the designer thought that that would be a good idea.

Now evolution provides an explanation for the stability of such proteins --- the explanation would be that they're not so useless that their presence or absence is invisible to natural selection. This also explains why we have found no mechanism (except natural selection) to maintain their stability.

A design hypothesis has to arbitrarily attribute a whim to the designer in order to explain the conservation of these proteins; it certainly cannot predict their existence; and cannot by itself explain why we have found no mechanism (except natural selection) to conserve them.

Edited by Dr Adequate, : No reason given.


This message is a reply to:
 Message 329 by Genomicus, posted 06-07-2012 5:18 PM Genomicus has responded

Replies to this message:
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pandion
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Posts: 166
From: Houston
Joined: 04-06-2009


(3)
Message 333 of 337 (665107)
06-08-2012 1:54 AM


As a former biology teacher, I have no problem with teaching ID.

Here is my lesson:

Some people believe that all life was intelligently designed. However, here are the facts that have been revealed by observation, hypothesis, prediction, and testing.

That's from minute one. The topic has been covered.


  
Genomicus
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Posts: 846
Joined: 02-15-2012


Message 334 of 337 (665159)
06-08-2012 9:03 PM
Reply to: Message 330 by PaulK
06-07-2012 5:48 PM


Re: There is nothing to teach about ID other than as an example of pseudoscience.
However, whatever it was, it would not be expected to have a minimal gene set for whatever it was, would it ? Simplicity is more an aim of design rather than evolution. Once evolution gets going we should expect more complexity than is strictly needed.

Yes, but as I stated earlier, there is nothing at all stopping some early population composed of self-replicating molecules from branching off and diverging into Archaea and Bacteria - under the non-telic model. But under front-loading, you have to load the genome with functional but unnecessary proteins. FL doesn't work otherwise.

Isn't your argument that there genes going back to the LUCA which are NOT part of a minimal set ? Surely homology tests will - at most - show if the LUCA likely had a homologous gene or not ?

Homology comparisons between a eukaryotic protein and a prokaryotic protein will determine if the two proteins are indeed homologous; to determine if the prokaryotic protein was part of a minimal set (i.e., that it evolved from a protein that is necessary for the existence of life), we'd need to trace the homology deeper and see if it shares any homology with proteins in prokaryotes that are needed for life (such as DNA replication machinery, etc.)

Suppose that rather than there being NO minimal gene sets that allowed for the evolution of life that we see today there were a VERY FEW - a very small proportion - that did. Wouldn't then, a LUCA with one of those gene-sets be entirely compatible with the concept of front-loading ?

The issue isn't so much about whether a minimum gene set could allow the appearance of the taxa we see today. Given an initial genome that only has the most crucial proteins to life, evolution could have taken many different directions - including the direction of life forms as we see them today.

However, if the front-loading designer(s) intended for a specific outcome, you'd have to load the first genomes with proteins - like globins, tubulin analogs, etc. - such that evolution would build on those proteins and the future of evolution would be shaped, and the origin of animals and plants would be much more likely. That's why you'd need to load the initial genomes with unnecessary (but functional!) proteins.

For it to be a prediction, you have to show that a minimal gene set doesn't provide the flexibility needed - especially given the time available - and you haven't done that.

A minimal gene set could evolve in a plethora of directions - including plants and animals. But, speaking from a probabilistic standpoint, with just a minimal gene set, the odds of animals and plants appearing on the scene are quite low, since there are many alternatives. For example, how plausible is it that SecY (which is, IIRC, a protein essential to all life) will evolve into hemoglobin, since they are not at all nearby in sequence space, and there are a multitude of possible proteins SecY could potentially evolve into. And this means that the animals you want to appear on the scene of life will very probably not appear. However, if you load a genome with globins, then it's quite likely that some form of blood will evolve, allowing the appearance of animal-like life forms.


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 Message 330 by PaulK, posted 06-07-2012 5:48 PM PaulK has not yet responded

  
Genomicus
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Message 335 of 337 (665161)
06-08-2012 9:08 PM
Reply to: Message 332 by Dr Adequate
06-07-2012 6:14 PM


Re: Whimsical Design
In order to say that the conservation of such-and-such proteins would not be part of an evolutionary prediction, you have to suppose them to have so little use that natural selection would not conserve them. As you say, such a protein needs to be of so little use that "deleting it won't kill the organism, or even significantly reduce its fitness" --- and the significance of its contribution to fitness must in fact be so tiny that selective pressure won't prevent its deletion from becoming fixed in a population.

I really don't think you're understanding my argument. It's very simply this:

1. Non-teleological evolution does not predict that the LUCA's genome would encode proteins unnecessary - but functional - to life.

2. Front-loading necessarily predicts this.

Confirmation of this prediction therefore, would boost our confidence in FL. And the more instances we find of this, the higher our confidence becomes.


This message is a reply to:
 Message 332 by Dr Adequate, posted 06-07-2012 6:14 PM Dr Adequate has not yet responded

  
Dr Adequate
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Message 336 of 337 (665165)
06-08-2012 10:24 PM


Thread Closing
As the thread has closed for all but summations, it seems futile to quiz Genomicus on the reason for his assertions. I shall just content myself with pointing out some of the problems.

* We have no evidence that any of these proteins was inessential to LUCA.

* Looking around at organisms today, we have every reason to suppose that anything as advanced as LUCA (recall that it is the last universal common ancestor) would possess proteins the absence of which would not have been fatal under all circumstances, but which would have been inconvenient, and would have been selected against.

* Without any mechanism for how front-loading works, we can hardly place constraints on what LUCA would have been like in order for front-loaded evolution to occur.

* It is on evolutionary grounds alone that we deduce what proteins LUCA had from the study of modern organisms. Without a mechanism for front-loading, we have no reason to say which proteins LUCA would or wouldn't have. And clearly we can have no warrant to use an evolutionary reconstruction of LUCA to support a front-loading hypothesis.

* Now, given that we cannot see LUCA and that front-loaders cannot, without additional hypotheses deduce anything about LUCA, it is plain that my car-with-a-fireplace analogy holds. For what we see are modern organisms: organisms to which these proteins must be (as Genomicus has claimed but has not proved) about as much use as a fireplace to a car. FLE does not predict that we should observe these phenomena; but also it does not even adequately explain them, since no mechanism is even posited, much less demonstrated, for their preservation (natural selection being, by G's hypothesis, insufficient); nor, of course, any motive for the designer in wishing to preserve them by this undiscovered mechanism.

So: evolution explains the distribution of these proteins in modern organisms by saying that they're basal and are preserved by natural selection. FLE, as Genomicus has so far expounded it, provides no explanation for either how (mechanism) or why (motive of the Designer) they should exist in modern species --- and gives us no warrant for thinking them basal, since that is a conclusion drawn from the premise that evolutionary processes are responsible.

Maybe this could be continued on another thread.

---

As for the problem with teaching ID (apart from the whole First Amendment thing) it would be that they don't seem to have got anywhere. They know the sort of things they'd like to be able to do, but they haven't actually done them.

Edited by Dr Adequate, : No reason given.

Edited by Dr Adequate, : No reason given.


  
PaulK
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Member Rating: 1.9


Message 337 of 337 (665171)
06-09-2012 7:14 AM


Front Loading
It is rather unclear what the Front Loading hypothesis has to do with the subject since the evidence offered is at present only speculative at best. However, we can see that the argument is very much overstated.

First, given non-telic evolution it is very unlikely that the LUCA would have a minimal gene set. Evolution tends to unnecessary complexity, and if the additional genes are advantageous even a scenario where they are pruned away is extremely unlikely.

When we include horizontal gene transfer the problem becomes even more acute since the LUCA and ancestors near it would be expected to acquire and keep additional advantageous genes.

Given the massive horizontal gene transfer expected to occur, the LUCA must not only have a minimal gene set, all it's peers must have the same minimal gene set. This would seem to be far more likely given Directed Panspermia, than evolution - intentional engineering would be better equipped to produce a functional organism with a minimal gene set, and arrival from elsewhere would explain the absence of any rivals.

We must also be aware that Front Loading does not in itself predict a preference for particular proteins found in modern life. There must be some proposed advantage for including the specified genes for the designers. Without that we are in a "the designer likes giraffes" scenario.

Also, Front Loading does not predict that the Front Loaders intentions cannot be carried out by some minimal gene set. At least not without constructing hypotheses about their intentions which has not been done. Given that a LUCA with a minimal gene set is more easily obtained by design than by evolution, it seems that the argument at p resent favours non- telic evolution until we come up with hypotheses about what was "Front Loaded" and why. As I state above a simple assumption that particular proteins were favoured, without reason why they were favoured is wholly inadequate.

To sum up:

1) we have good reason to expect that evolution would not be limited to the genes from a single, minimal gene set. Such a limitation is more easily explained by the Directed Panspermia favoured by the proponents of Front Loading.

2) it has not yet been shown that there are any genes with deep homology that are not derived from a minimal gene set.

3) at this time there is no plausible hypothesis why the Front Loaders would include extra genes anyway


    
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