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Author Topic:   Deep Homology and Front-loading
Genomicus
Member (Idle past 1218 days)
Posts: 852
Joined: 02-15-2012


Message 61 of 172 (666110)
06-22-2012 12:22 AM
Reply to: Message 59 by Dr Adequate
06-22-2012 12:08 AM


Re: The Ubiquitin Story
Distant indeed --- between proteins which do different things and have only a small amount of their sequence in common. Homology? Well maybe --- if you're a Darwinian. But do you want to suggest that these different proteins adapted to doing different things have a common ancestor?

Actually, these proteins carry out analogous functions. And, again, sequence isn't everything. Structural homology is also important, and it's more likely to be detected given the deep-time involved. I really have no idea why you think that one has to be a Darwinian in order to accept the view that these proteins are homologous.

I'd have expected more front-loading of information and less Darwinian evolution.

Huh? You do know that front-loading works with the blind watchmaker, and not against it? So I'm not sure how to make sense out of "more front-loading of information and less Darwinian evolution."

And yet you have no evidence that ubiquitin was the common ancestor of this protein family, if it is one.

Well, the structural evidence coupled to other clues does indicate that these proteins are likely homologous. At any rate, now you're moving the goal-posts. First, you said that ubiquitin has no prokaryotic homologs (inconsistent with FLE), while structural analyses suggest otherwise. And now you want us to actually build a phylogeny of all these distantly related proteins to determine if the common ancestor was ubiquitin.

Anyway, you wouldn't have to load the first cells with ubiquitin itself. You'd simply need to load them with closely related proteins, so that when eukaryotes do appear on the scene of life, they can easily co-opt the proto-ubiquitin into its modern role.

Edited by Genomicus, : No reason given.


This message is a reply to:
 Message 59 by Dr Adequate, posted 06-22-2012 12:08 AM Dr Adequate has replied

Replies to this message:
 Message 63 by Dr Adequate, posted 06-22-2012 12:48 AM Genomicus has replied

  
Genomicus
Member (Idle past 1218 days)
Posts: 852
Joined: 02-15-2012


Message 62 of 172 (666111)
06-22-2012 12:24 AM
Reply to: Message 60 by Dr Adequate
06-22-2012 12:20 AM


Re: Evidence And Prediction
So you believe that all extant species descended from a common ancestor by purely Darwinian mechanisms?

Yes. What did you think my position was? That intelligent intervention occurred for the origin of all species or that the origin of species was "programmed" somehow?

Well, I hate to break it to you, but someone got in ahead of you there ... it was Darwin. This is certainly not what is usually understood by front-loaded evolution.

Okay. What is your understanding of front-loading? I'm taking Mike Gene's position here, by the way.


This message is a reply to:
 Message 60 by Dr Adequate, posted 06-22-2012 12:20 AM Dr Adequate has replied

Replies to this message:
 Message 64 by Dr Adequate, posted 06-22-2012 12:56 AM Genomicus has replied

  
Dr Adequate
Member (Idle past 328 days)
Posts: 16112
Joined: 07-20-2006


(1)
Message 63 of 172 (666113)
06-22-2012 12:48 AM
Reply to: Message 61 by Genomicus
06-22-2012 12:22 AM


Re: The Ubiquitin Story
Actually, these proteins carry out analogous functions.

Well, no they don't. For example, according to this, the ThiS gene which you mention "plays a central role in thiamin biosynthesis". Unlike ubiquitin, which does something completely different. In fact, he writes: "Comparison with surface features of ubiquitin and ubiquitin homologs SUMO-1, RUB-1 and NEDD8 suggest how Nature has utilized this single fold to incorporate similar chemistry into a broad array of highly specific biological processes." The homologues do "highly specific" different things. And MoaD, which you also cite, is apparently "involved in molybdenum cofactor (Moco) biosynthesis".

I really have no idea why you think that one has to be a Darwinian in order to accept the view that these proteins are homologous.

Well, because the descent of different proteins doing different things from a common ancestor is Darwinian. If each protein was separately front-loaded into LUCA, that would be an instance of front-loading.

Well, the structural evidence coupled to other clues does indicate that these proteins are likely homologous. At any rate, now you're moving the goal-posts. First, you said that ubiquitin has no prokaryotic homologs (inconsistent with FLE) ...

The paper I found said that there were no prokaryotic homologues. Changing my mind when presented with new data is hardly moving the goalposts, it's what people are meant to do.

Anyway, you wouldn't have to load the first cells with ubiquitin itself. You'd simply need to load them with closely related proteins, so that when eukaryotes do appear on the scene of life, they can easily co-opt the proto-ubiquitin into its modern role.

If you're going to admit common descent of ThiS, MOAD, and the ubiquitin family, then a protein closely related to ubiquitin isn't necessary. Why not start with something more like ThiS? In which case, why not start with something pretty much like a prokaryote? The more homologies you claim, the greater the power you cede to purely Darwinian processes, and the less the need to "stack the deck".

(Consider if you showed me that all proteins were homologues descended from a single common ancestor. Would that be a point in favor of FLE?)

If you are prepared to say that without front-loading of the different genes, but just Darwininly (is that a word?) ThiS and ubiquitin descended from a common ancestor, when they do completely different things and have only 14% of their gene in common (according to WP) then I don't see why you should also think that there is any need whatsoever for any form of foresightful front-loading to produce eukaryotes.

Edited by Dr Adequate, : No reason given.


This message is a reply to:
 Message 61 by Genomicus, posted 06-22-2012 12:22 AM Genomicus has replied

Replies to this message:
 Message 67 by Genomicus, posted 06-22-2012 10:39 PM Dr Adequate has replied

  
Dr Adequate
Member (Idle past 328 days)
Posts: 16112
Joined: 07-20-2006


(1)
Message 64 of 172 (666114)
06-22-2012 12:56 AM
Reply to: Message 62 by Genomicus
06-22-2012 12:24 AM


Re: Evidence And Prediction
Yes. What did you think my position was? That intelligent intervention occurred for the origin of all species or that the origin of species was "programmed" somehow?

That's what it usually means. Typically, it is proposed as an origin for genetic information other than a Darwinian one. This involves information being differentially lost from different lineages. If you are prepared to admit that purely Darwinian processes can add useful new information to the pool, then really what's the need to front-load anything? Just start with something that's alive, and then let mutation, selection, etc, take it from there.


This message is a reply to:
 Message 62 by Genomicus, posted 06-22-2012 12:24 AM Genomicus has replied

Replies to this message:
 Message 81 by Genomicus, posted 06-25-2012 9:24 PM Dr Adequate has replied

  
PaulK
Member
Posts: 17171
Joined: 01-10-2003
Member Rating: 2.6


(1)
Message 65 of 172 (666115)
06-22-2012 1:32 AM
Reply to: Message 51 by Genomicus
06-21-2012 10:17 PM


quote:

Quite right. But they have to include the 250 or so genes necessary for carbon-based life forms to exist. And they'd add extra genes to the original genomes so that front-loading could follow.

Again, you are just repeating your assumption.

quote:

Okay, let me get your position right: are you suggesting that the designers could engineer the 250 genes needed for life such that they also favor the trajectory of evolution in the direction of Metazoa etc.?

I am suggesting that it is possible that they might be able to engineer the proteins to favour an evolutionary trajectory that would produce the features that they were interested in, yes. I don't accept that those possibilities are only satisfied by the metazoa as we know them.

quote:

Not sure what you mean by all of the above. Care to elaborate?

Your standard for prediction seems to require absolute certainty, because you reject near-certainties as predictions when they come from the evolutionary side. Obviously to meet this standard you need a very strong argument that a gene set of 250 proteins is inadequate even with the advantages of engineering.

I don't see any such argument from you at all. I don't see anything more than an opinion supported only by intuition. Indeed you can't even say how you could front-load the introduction of mitochondria to a standard you would consider adequate, nor offer any reason why the proposed designers might not start off by including something equivalent to basal eukaryotes in their biological package. Or indeed, finding some other solution to the engineering problem that mitochondria solve.


This message is a reply to:
 Message 51 by Genomicus, posted 06-21-2012 10:17 PM Genomicus has replied

Replies to this message:
 Message 82 by Genomicus, posted 06-25-2012 9:48 PM PaulK has replied

  
Genomicus
Member (Idle past 1218 days)
Posts: 852
Joined: 02-15-2012


Message 66 of 172 (666166)
06-22-2012 10:16 PM
Reply to: Message 45 by bluegenes
06-21-2012 7:28 PM


Re: I predict "No LUCA"!
I'm suggesting that, on any hypothetical planet that was front loaded with the deck stacked in favour of multicellular life, the equivalent of eukaryotes and whatever simple multicellular organisms that could survive should be there.

Well, eukaryotes aren't as good terra-formers as bacteria, and for front-loading to work on an originally hostile planet, you'd need to terra-form it such that it'll eventually be friendly to complex life forms, like mice and rabbits and trees (and of course, giraffes) etc. Also, although some eukaryotes can survive extreme environments, prokaryotes are far at surviving extreme environments. Furthermore, since I envision the first life forms arriving on earth via directed panspermia, the eukaryotes would have to survive the space voyage from their home planet to earth.

One more point. Some researchers have in fact proposed that the LUCA was effectively a eukaryote (albeit lacking mitochondria), with prokaryotes "degenerating" from the LUCA.

But why does FLE predict this? As we've agreed, the frontloaders could've made their own eukaryotes. Also, as Darwinian processes take place after the frontloading, then why should we expect all important proteins in modern eukaryotes to have homologues in modern prokaryotes even if the FrontLoaders didn't think of making their own eukaryotes?

I think I've already explained the rationale for this prediction in the OP, but, briefly, given that modern eukaryotes would have been front-loaded under my hypothesis, you'd need to ensure that the genes necessary for their origin would be present before their origin, i.e., in prokaryotes. So you'd load the genomes up with proteins that are necessary for the rise of eukaryotes. And we can detect this by looking for homologs of key eukaryotic proteins in prokaryotes. For example, Pax-6 (an important eukaryotic protein) has no known real prokaryotic homolog AFAIK. From the perspective of front-loading, then, I predict that one of these days we'll find a prokaryotic homolog of Pax-6.

Ubiquitin is another example. Prior to structural analyses of various prokaryotic proteins, there were no known prokaryotic homologs of ubiquitin. The logic of front-loading predicts otherwise, and indeed, research has uncovered deep homology between ubiquitin and prokaryotic proteins.

Me too. For an evidence based case, it's best to assume biological aliens. However, as I suggested, this still makes it hard to make predictions when we know nothing of their technical ability and the processes used. Intuitively, it does at least give us a reason why, being multicellular life forms themselves, they might be interested in the kind of project you're suggesting!

I freely admit that much of the time I'm following my intuition when it comes to the hypothesis of front-loading. My intuition is fallible of course, but that's why I'm not asking any of you to accept front-loading as a valid science at the moment. As I stated earlier, there are many hurdles facing the FL hypothesis.

Of course, critics of your hypothesis might wonder, if it took 4,000,000,000 yrs for intelligent biologists to emerge from this "stacked-deck" biosphere, how long it took for them to emerge on their "unstacked-deck" planet.

Well, there's a lot of time for the nanotechnologists to emerge on a planet that is older then the earth.

Maybe we can at least get a Sci-fi novel out of this, if nothing else.


This message is a reply to:
 Message 45 by bluegenes, posted 06-21-2012 7:28 PM bluegenes has replied

Replies to this message:
 Message 87 by bluegenes, posted 06-26-2012 8:24 AM Genomicus has replied

  
Genomicus
Member (Idle past 1218 days)
Posts: 852
Joined: 02-15-2012


Message 67 of 172 (666167)
06-22-2012 10:39 PM
Reply to: Message 63 by Dr Adequate
06-22-2012 12:48 AM


Re: The Ubiquitin Story
Well, no they don't. For example, according to this, the ThiS gene which you mention "plays a central role in thiamin biosynthesis". Unlike ubiquitin, which does something completely different.

Yes, but, from the same paper you cite:

"Although ThiS shares only 14% sequence identity with ubiquitin, it possesses the ubiquitin fold. This structural homology, combined with established functional similarities involving sulfur chemistry, demonstrates that the eukaryotic ubiquitin and the prokaryotic ThiS evolved from a common ancestor. This illustrates how structure determination is essential in establishing evolutionary links between proteins in which structure and function have been conserved through eons of evolution despite loss of sequence identity."

I admit that it was a bit of a stretch to say that these proteins carry out analogous functions. But they have key functional similarities.

Well, because the descent of different proteins doing different things from a common ancestor is Darwinian. If each protein was separately front-loaded into LUCA, that would be an instance of front-loading.

Yes, but loading up the first genomes with proteins similar to ubiquitin would ensure that they'd be around before the appearance of Metazoa, so the front-loaders wouldn't have to depend on the blind watchmaker to "just happen" to find ubiquitin, allowing the origin of Metazoa.

Changing my mind when presented with new data is hardly moving the goalposts, it's what people are meant to do.

Well, yes, but you actually expect a robust phylogeny of ubiquitin and its prokaryotic homologs?

If you're going to admit common descent of ThiS, MOAD, and the ubiquitin family, then a protein closely related to ubiquitin isn't necessary. Why not start with something more like ThiS? In which case, why not start with something pretty much like a prokaryote? The more homologies you claim, the greater the power you cede to purely Darwinian processes, and the less the need to "stack the deck".

ThiS, MOAD, and ubiquitin are all structurally related, so you'd need to load the genome with a structurally similar protein. I have no idea where you're going with "The more homologies you claim, the greater the power you cede to purely Darwinian processes, and the less the need to 'stack the deck'."

(Consider if you showed me that all proteins were homologues descended from a single common ancestor. Would that be a point in favor of FLE?)

Okay, by this do you mean that, e.g., cytochrome c, hemoglobin, insulin, etc., are (in this hypothetical scenario) all descended from a common ancestor?

If you are prepared to say that without front-loading of the different genes, but just Darwininly (is that a word?) ThiS and ubiquitin descended from a common ancestor, when they do completely different things and have only 14% of their gene in common (according to WP) then I don't see why you should also think that there is any need whatsoever for any form of foresightful front-loading to produce eukaryotes.

Precisely because without putting a protein that is structurally similar to ubiquitin in the first genomes, you'd have to depend on the blind watchmaker to tinker around with the existing folds, and "just happen" to come up with a protein that is structurally similar to ubiquitin (and also happens to have the necessary sulfur chemistry).

Anyhew, I'll be back after the weekend and respond to the other posts.


This message is a reply to:
 Message 63 by Dr Adequate, posted 06-22-2012 12:48 AM Dr Adequate has replied

Replies to this message:
 Message 68 by Dr Adequate, posted 06-23-2012 1:21 AM Genomicus has replied
 Message 69 by Dr Jack, posted 06-23-2012 8:53 AM Genomicus has taken no action
 Message 71 by New Cat's Eye, posted 06-25-2012 11:38 AM Genomicus has replied

  
Dr Adequate
Member (Idle past 328 days)
Posts: 16112
Joined: 07-20-2006


(2)
Message 68 of 172 (666169)
06-23-2012 1:21 AM
Reply to: Message 67 by Genomicus
06-22-2012 10:39 PM


Re: The Ubiquitin Story
I admit that it was a bit of a stretch to say that these proteins carry out analogous functions. But they have key functional similarities.

Presumably involving the structural similarity they have in common.

But they do do radically different things.

Yes, but loading up the first genomes with proteins similar to ubiquitin would ensure that they'd be around before the appearance of Metazoa, so the front-loaders wouldn't have to depend on the blind watchmaker to "just happen" to find ubiquitin, allowing the origin of Metazoa.

Well, how similar? If members of this superduper protein family can differ by as much as 86% in their structure, and can differ completely as to the role they play in the cell, and if you're prepared to put that down to Darwinian mechanisms, then the blind watchmaker is starting to look pretty good at his job, isn't he?

Well, yes, but you actually expect a robust phylogeny of ubiquitin and its prokaryotic homologs?

I don't follow you.

ThiS, MOAD, and ubiquitin are all structurally related, so you'd need to load the genome with a structurally similar protein. I have no idea where you're going with "The more homologies you claim, the greater the power you cede to purely Darwinian processes, and the less the need to 'stack the deck'."

Well, you claim, do you not, that after LUCA the designers just let Darwinian processes get on with it. And you claim, do you not, that ThiS and MOAD and the ubiquitin family are all homologues rather than being separately front-loaded, don't you? In which case you ascribe the differences between them in form and function to the blind watchmaker, don't you? In which case, as I say, he must be quite good at his job.

Well, having admitted that much, does it seem so implausible that the blind watchmaker is also responsible for producing the one thing that ThiS and MOAD and ubiquitin do have in common, at some period prior to LUCA? Once you've said that known and observable processes such as mutation and natural selection can do so much to the form and function of proteins, why postulate an extra unobserved hypothetical mechanism to do one little bit more?

As I said in another post, FLE is usually the choice of people who have fallen for bad arguments for the impotence of Darwinian mechanisms. You, on the other hand, seem to think that these mechanisms are very powerful.

There are those who think that building the Great Pyramid was so far beyond the ability of ancient Egyptians that the work must have been done by space aliens. There are those who think that building the Great Pyramid was well within Egyptian capacities. But what would you say to someone who said: "I think that aliens started the Egyptians off by laying the first layer of stones, but I'm confident that they could easily have finished the rest themselves"? I think you'd say something along the lines of: "If you have such confidence in ancient Egyptian technology, why drag any aliens into it?"

Okay, by this do you mean that, e.g., cytochrome c, hemoglobin, insulin, etc., are (in this hypothetical scenario) all descended from a common ancestor?

Yes. If that was the case, would it be a point in favor of FLE or a point against it?

Precisely because without putting a protein that is structurally similar to ubiquitin in the first genomes, you'd have to depend on the blind watchmaker to tinker around with the existing folds, and "just happen" to come up with a protein that is structurally similar to ubiquitin (and also happens to have the necessary sulfur chemistry).

The "and" there is superfluous. If you admit that all the homologues really are homologues, then the only respect in which the parent molecule has to be similar to ubiquitin is in possessing the one property that the homologues actually have in common. After that you just step back and let the blind watchmaker do his non-magic.


This message is a reply to:
 Message 67 by Genomicus, posted 06-22-2012 10:39 PM Genomicus has replied

Replies to this message:
 Message 83 by Genomicus, posted 06-25-2012 10:19 PM Dr Adequate has replied

  
Dr Jack
Member (Idle past 1381 days)
Posts: 3507
From: Leicester, England
Joined: 07-14-2003


(1)
Message 69 of 172 (666175)
06-23-2012 8:53 AM
Reply to: Message 67 by Genomicus
06-22-2012 10:39 PM


Re: The Ubiquitin Story
Precisely because without putting a protein that is structurally similar to ubiquitin in the first genomes, you'd have to depend on the blind watchmaker to tinker around with the existing folds, and "just happen" to come up with a protein that is structurally similar to ubiquitin (and also happens to have the necessary sulfur chemistry).

What makes you think either the sulphur chemistry or the protein fold is necessary?

Ubiquitin is a signalling molecule that interact with other proteins. I'm not aware of any reason to think that it isn't arbitrary which features of Ubiquitin are required for it to function; all it needs is the correct "lock and key" interaction with the various other proteins it interacts with.

Edited by Mr Jack, : Missed a not


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Dr Adequate
Member (Idle past 328 days)
Posts: 16112
Joined: 07-20-2006


(1)
Message 70 of 172 (666199)
06-23-2012 9:49 PM
Reply to: Message 69 by Dr Jack
06-23-2012 8:53 AM


Re: The Ubiquitin Story
I didn't follow that, I don't see why Genomicus would.

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New Cat's Eye
Inactive Member


Message 71 of 172 (666269)
06-25-2012 11:38 AM
Reply to: Message 67 by Genomicus
06-22-2012 10:39 PM


Re: The Ubiquitin Story
Nice thread, Geno.

Precisely because without putting a protein that is structurally similar to ubiquitin in the first genomes, you'd have to depend on the blind watchmaker to tinker around with the existing folds, and "just happen" to come up with a protein that is structurally similar to ubiquitin (and also happens to have the necessary sulfur chemistry).

But how unlikely is it, really? Maybe its inevitable, no? Given that its all spontaneous chemistry, and that proteins work because of thier shape, why wouldn't we expect these kinds of similarities even without FLE?


This message is a reply to:
 Message 67 by Genomicus, posted 06-22-2012 10:39 PM Genomicus has replied

Replies to this message:
 Message 94 by Genomicus, posted 06-26-2012 1:29 PM New Cat's Eye has replied

  
Taq
Member
Posts: 8524
Joined: 03-06-2009
Member Rating: 5.0


(2)
Message 72 of 172 (666274)
06-25-2012 12:39 PM
Reply to: Message 12 by Genomicus
06-20-2012 11:59 AM


Let's take a look at calmodulin (CaM) as an example. Calmodulin binds to calcium and is found universally among eukaryotes. This fact, coupled to the observation that its sequence identity is exceptionally conserved across taxa, suggests that eukaryotes require calmodulin for their existence. In a world without calmodulin (or a functional analog), would eukaryotes exist? Probably not.

This quote exemplifies the problems with FLE. It is Texas Sharpshooting, plain and simple. The Texas Sharpshooter falacy is where a sharpshooter makes the claim that he can hit a target the size of a quarter from 1,000 yards away on the first try. The sharpshooter fires his shot into a crowded suburb, finds the bullet hole (presumably in the side of a house), and draws a quarter sized bull's eye around the bullet hole. Voila, amazing sharpshooting exhibition, right?

This is exactly what FLE is. It assumes that the biodiversity we see today is the biodiversity that was intended. Genomicus is drawing the bull's eye around the bullet hole. What Genomicus just can't understand is that eukaryotes DID NOT NEED TO EVOLVE. There is nothing in the history of life that requires the existence of eukaryotes, much less eukaryotes with calmodulin. NOTHING. It is a happenstance of occurences that resulted in eukaryotes evolving. If we went back in time before eukaryotes emerged could we use FLE to predict that eukaryotes would emerge, and that they would all require calmodulin? No. Genomicus has not put forward one methodology within FLE for predicting which proteins will become important in future lineages. None. All FLE does is look at what did evolve and then claim that this was the target. This is Texas Sharpshooting.

Even worse, the predictions of FLE are exactly what we would predict from the non-teleological process of evolution. Evolution is descent with modification. What is the prediction of FLE? Descent with modification. FLE can not, and does not, differentiate itself from observed non-teleological processes. FLE is sliced neatly away by Occam's Razor.


This message is a reply to:
 Message 12 by Genomicus, posted 06-20-2012 11:59 AM Genomicus has replied

Replies to this message:
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Taq
Member
Posts: 8524
Joined: 03-06-2009
Member Rating: 5.0


(2)
Message 73 of 172 (666276)
06-25-2012 12:50 PM
Reply to: Message 1 by Genomicus
06-19-2012 2:46 PM


From here we can make a prediction: key eukaryotic proteins will share deep homology with functional but unnecessary prokaryotic proteins.

This is also what we would expect from non-teleological processes like evolution. In fact, Hermann Muller predicted that evolution would produce these relationships clear back in 1918:

quote:
Most present day animals are the result of a long process of evolution, in which at least thousands of mutations must have taken place. Each new mutant in turn must have derived its survival value from the effect which it produced upon the "reaction system" that had been brought into being by the many previously formed factors in cooperation; thus a complicated machine was gradually built up whose effective working was dependent upon the interlocking action of very numerous elementary parts or factors, and many of the characters are factors which, when new, where originally merely an asset finally become necessary because other necessary characters and factors had subsequently become changed so as to be dependent on the former. It must result, in consequence, that a dropping out of, or even a slight change in any one of these parts is very likely to disturb fatally the whole machinery . . . [emphasis mine]

"Genetic Variablity, Twin Hybrids and Constant Hybrids, in a Case of Balanced Lethal Factors", by Hermann J Muller, in Genetics, Vol 3, No 5, Sept 1918, pp 422-499.


You also make the mistake of equating unnecessary with useless. You leave competition out of the equation. Let's use cars as an analogy. We could design a car with a bare minimum of parts. This car would be functional, but it would be slow, wouldn't corner well, and would be very unsafe. However, it would fulfill its role as a mode of transportation. As we all know, life is about competition. What traits are passed on is the result of competition for limited resources. To model this situation, let's have the cars race each other. How well would this minimalistic car do? Not well at all. It would lose rather horribly.

One of the MAJOR problems with your model is assuming that a minimalistic genome comprised of only "necessary" proteins would be viable. It wouldn't.


This message is a reply to:
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New Cat's Eye
Inactive Member


(2)
Message 74 of 172 (666294)
06-25-2012 2:35 PM
Reply to: Message 72 by Taq
06-25-2012 12:39 PM


This quote exemplifies the problems with FLE. It is Texas Sharpshooting, plain and simple.

I was noticing that too, but couldn't remember the name of the fallacy. I was thinking that this looked an aweful lot like saying the pothole was designed to fit around the puddle, its just that were zooming in to the individual water molecules interacting with the concrete ones.

I was going to mention to Geno that it looked like he already liked FLE, and then went looking for evidence that can be shoehorned into it, rather than coming to a conclusion of FLE from the evidence that he had found.


This message is a reply to:
 Message 72 by Taq, posted 06-25-2012 12:39 PM Taq has replied

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Taq
Member
Posts: 8524
Joined: 03-06-2009
Member Rating: 5.0


(2)
Message 75 of 172 (666297)
06-25-2012 3:55 PM
Reply to: Message 74 by New Cat's Eye
06-25-2012 2:35 PM


I was going to mention to Geno that it looked like he already liked FLE, and then went looking for evidence that can be shoehorned into it, rather than coming to a conclusion of FLE from the evidence that he had found.

Quite right. A more scientific approach would be to derive the ancestral genome and then demonstrate from first principles which genes were front loaded without pointing to modern genomes. Geno doesn't do this. At best, he claims that unnecessary genes will be passed on to subsequent generations where they would either be selected against if they became completely useless, or selected for if they evolved a more important role. This is evolution, no front loading needed.

Geno might as well predict that of the millions of lottery tickets, one of them will be a winner. In fact, the lottery is front loaded so that a specific ticket will win. Which ticket is the lottery front loaded for? Well, you have to wait for the drawing to figure that out. IOW, FLE is nothing more than the hope of some supernatural guidance in a nominally non-teleologic process.


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 Message 74 by New Cat's Eye, posted 06-25-2012 2:35 PM New Cat's Eye has replied

Replies to this message:
 Message 76 by New Cat's Eye, posted 06-25-2012 4:57 PM Taq has replied
 Message 78 by bluegenes, posted 06-25-2012 6:16 PM Taq has replied
 Message 105 by Genomicus, posted 06-26-2012 4:24 PM Taq has replied

  
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