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Author Topic:   Deep Homology and Front-loading
Genomicus
Member (Idle past 1941 days)
Posts: 852
Joined: 02-15-2012


Message 16 of 172 (665980)
06-20-2012 1:31 PM
Reply to: Message 13 by Dr Adequate
06-20-2012 1:02 PM


But is there anything in FLE that predicts that such a thing should exist? Would it not be compatible with FLE that everything that's essential to eukaryotes should also be essential to prokaryotes? Where does FLE rule that out?
Huh? It's not FLE that rules that out, it's basic observations that rule it out. And the FLE hypothesis is built around biological observations, such as the fact that not everything that is essential to the eukaryotic cell structure is required for the existence of the prokaryotic cell structure. I'm not arguing in favor of this hypothesis on the basis of what ifs, such as "what if everything that is essential to eukaryotes is also essential to prokaryotes?" It's on the basis of known biological facts that this hypothesis is constructed upon.
Well, suppose that prokaryotes started off with a certain set of genes, let's call them genes 1 ... 1000. Then gene 1001 arises by the mechanisms you suggest, and substitutes for gene 1 and displaces it, and then gene 1002 arises by the mechanisms you suggest, and substitutes for gene 2 and displaces it ... and so on until every gene in LUCA has been substituted by a gene arising by the mechanisms you postulate.
I'm not suggesting anything like that happened. I'm saying that some key eukaryotic proteins, under the non-telic model, could have evolved through patching together different chunks of non-coding sequences.
You believe, do you not, in random mutation and in natural selection?
Quite right.
Therefore, you believe in "non-telic evolution" don't you?
If that's how you're defining "non-telic evolution," then yes. But when I say "non-telic evolution" I mean this whole non-teleological framework which says that planning and foresight was not involved in the origin of genetic diversity on earth (with the exception of human intervention).
But as I have pointed out before, our ability to look "indirectly" at LUCA depends crucially on accepting Darwinian evolution. That is the theory which allows us to infer LUCA. If we deny Darwinism, we have no basis on which to say what LUCA looked like.
And, in this context, what does "Darwinism" mean? Random mutation coupled to natural selection (and similar mechanisms)?
(1) There are certain proteins that are essential to eukaryotes.
Yes.
(2) These proteins have homologues in prokaryotes such that prokaryotes would not actually drop dead if deprived of these proteins, but would be significantly disadvantaged if deprived of them.
Specifically, some prokaryotes might actually drop dead because scaffolding allows an originally unnecessary protein to become essential for a given species. But this protein would not be universally required for the overall prokaryotic cell plan.
How does FLE predict this state of affairs? How would I, or you, or anyone, reason from "LUCA was front-loaded" to this conclusion?
Let me try again:
1. Front-loading, by definition, involves loading the first genomes with proteins that are unnecessary for prokaryotes but are necessary for the origin of eukaryotes and multicellular life forms.
2. Thus, front-loading predicts that the important proteins in eukaryotes will share deep homology with proteins in prokaryotes which are unnecessary for the existence of prokaryotes. These functional but unnecessary proteins in prokaryotes are the descendants of the original proteins that were loaded into the first genomes.
Possibly I'm not being clear enough.

This message is a reply to:
 Message 13 by Dr Adequate, posted 06-20-2012 1:02 PM Dr Adequate has replied

Replies to this message:
 Message 23 by Dr Adequate, posted 06-20-2012 2:05 PM Genomicus has replied

  
Genomicus
Member (Idle past 1941 days)
Posts: 852
Joined: 02-15-2012


Message 17 of 172 (665981)
06-20-2012 1:35 PM
Reply to: Message 15 by jar
06-20-2012 1:30 PM


Re: Getting rid of bad stuff
If so, doesn't the prevailing view imply that random mutations that are NOT seriously damaging to the chance of reproduction get retained?
Not all neutral mutations will be retained by a population. Only some.

This message is a reply to:
 Message 15 by jar, posted 06-20-2012 1:30 PM jar has replied

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 Message 18 by jar, posted 06-20-2012 1:36 PM Genomicus has replied

  
jar
Member (Idle past 394 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 18 of 172 (665982)
06-20-2012 1:36 PM
Reply to: Message 17 by Genomicus
06-20-2012 1:35 PM


Re: Getting rid of bad stuff
LOL
And your point?

Anyone so limited that they can only spell a word one way is severely handicapped!

This message is a reply to:
 Message 17 by Genomicus, posted 06-20-2012 1:35 PM Genomicus has replied

Replies to this message:
 Message 20 by Genomicus, posted 06-20-2012 1:45 PM jar has replied

  
Genomicus
Member (Idle past 1941 days)
Posts: 852
Joined: 02-15-2012


Message 19 of 172 (665983)
06-20-2012 1:44 PM
Reply to: Message 14 by PaulK
06-20-2012 1:18 PM


The real question is whether it is possible to engineer a minimal gene set which would encourage the formation of complex life. Given the size of the minimal gene set that you suggest, it seems that that is at least something that could plausibly be true.
The minimal genome would be around 250 genes. You're basically suggesting that the designers take calmodulin and fashion it such that it is necessary for the prokaryotic cell plan, are you not?
Wouldn't it make a lot more sense to engineer eukaryotes with artificial mitochondria - if the engineers chose the symbiotic route at all?
Eukaryotes aren't very good terraformers compared to prokaryotes, and FL is intimately linked to terraforming. If you engineered the first bunch of cells in the right way, the origin of eukaryotes becomes quite likely. Thus we see that multicellularity has evolved independently several times, pointing to the plausibility of the evolution of multicellular life forms, given specific initial conditions.
If the LUCA is a population of organisms exchanging genes it would be expected to have a greater diversity of genes than if it were a single individual organism. And thus far more likely to have more than a minimal genome (in aggregate).
Yes, but the LUCA could also be a self-replicating RNA molecule, with - as you correctly point out - small amounts of molecular machinery needed for the formation of primitive proteins.
For the purposes of this discussion it is going to be better if you at least take the leading views of the origin of DNA as possibilities that have to be considered. To the best of my knowledge, the RNA World hypothesis is widely accepted among researchers into the origins of life.
Yes, but if I accept the RNA world hypothesis - that is, the thesis that life evolved from compounds on earth - my front-loading hypothesis is blown out of the water, effectively. So, when you suggest that I take the leading view that DNA evolved from RNA, you're essentially saying that I should take the leading view that teleology has not played a role in the history of life on earth.

This message is a reply to:
 Message 14 by PaulK, posted 06-20-2012 1:18 PM PaulK has replied

Replies to this message:
 Message 22 by PaulK, posted 06-20-2012 2:02 PM Genomicus has replied

  
Genomicus
Member (Idle past 1941 days)
Posts: 852
Joined: 02-15-2012


Message 20 of 172 (665984)
06-20-2012 1:45 PM
Reply to: Message 18 by jar
06-20-2012 1:36 PM


Re: Getting rid of bad stuff
I was merely doing my best to answer your question, jar. No need to get slightly snarky over it

This message is a reply to:
 Message 18 by jar, posted 06-20-2012 1:36 PM jar has replied

Replies to this message:
 Message 21 by jar, posted 06-20-2012 1:54 PM Genomicus has not replied

  
jar
Member (Idle past 394 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


(1)
Message 21 of 172 (665985)
06-20-2012 1:54 PM
Reply to: Message 20 by Genomicus
06-20-2012 1:45 PM


Re: Getting rid of bad stuff
It's not snarky nor does it attempt to answer my questions.
In case you missed the significant question, here it is yet again.
jar writes:
How can you determine is something was intentional or just dumb luck?

Anyone so limited that they can only spell a word one way is severely handicapped!

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 Message 20 by Genomicus, posted 06-20-2012 1:45 PM Genomicus has not replied

  
PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


Message 22 of 172 (665986)
06-20-2012 2:02 PM
Reply to: Message 19 by Genomicus
06-20-2012 1:44 PM


quote:
The minimal genome would be around 250 genes. You're basically suggesting that the designers take calmodulin and fashion it such that it is necessary for the prokaryotic cell plan, are you not?
Certainly not! I'm suggesting that it is plausible that there is a set of 250 genes that would encourage the evolution of complex life.
quote:
Eukaryotes aren't very good terraformers compared to prokaryotes, and FL is intimately linked to terraforming. If you engineered the first bunch of cells in the right way, the origin of eukaryotes becomes quite likely. Thus we see that multicellularity has evolved independently several times, pointing to the plausibility of the evolution of multicellular life forms, given specific initial conditions.
This seems to make it more likely that if FLH were true, that the designers would start with something like eukaryotes, at least in capabilities rather than try to arrange for a suitable endosymbiosis event to happen eventually.
quote:
Yes, but the LUCA could also be a self-replicating RNA molecule, with - as you correctly point out - small amounts of molecular machinery needed for the formation of primitive proteins.
I don't see that as very plausible, unless you assume that the LUCA was engineered.
quote:
Yes, but if I accept the RNA world hypothesis - that is, the thesis that life evolved from compounds on earth - my front-loading hypothesis is blown out of the water, effectively. So, when you suggest that I take the leading view that DNA evolved from RNA, you're essentially saying that I should take the leading view that teleology has not played a role in the history of life on earth.
I am not asking you to believe in the RNA world. I am saying that you have to accept it as
an important part of a serious opposing position. If you don't do that then you are committing something akin to the strawman fallacy.

This message is a reply to:
 Message 19 by Genomicus, posted 06-20-2012 1:44 PM Genomicus has replied

Replies to this message:
 Message 26 by Genomicus, posted 06-20-2012 3:24 PM PaulK has replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


(1)
Message 23 of 172 (665987)
06-20-2012 2:05 PM
Reply to: Message 16 by Genomicus
06-20-2012 1:31 PM


Huh? It's not FLE that rules that out, it's basic observations that rule it out.
* sighs, bangs head against desk *
You don't seem to have got the hang of this whole prediction thing.
Look, suppose you said that giraffes confirm FLE because FLE predicts giraffes.
And then I come back saying: "But is there anything in FLE that predicts that giraffes should exist? Would it not be compatible with FLE that there should be no giraffes? Where does FLE rule that out?"
And then you riposte with: "Huh? It's not FLE that rules that out, it's basic observations that rule it out."
These "basic observations", of course, being that we can see giraffes.
Don't you see that in order for a theory to predict X, it has to rule out not-X? You can't say: "My theory predicts X ... OK, I grant you it doesn't rule out not-X ... but we can see that X". Well in that case your theory hasn't made a prediction. We've just seen X.
I'm not suggesting anything like that happened. I'm saying that some key eukaryotic proteins, under the non-telic model, could have evolved through patching together different chunks of non-coding sequences.
But unless you claim that it is a prediction of Darwinism that there should most likely have been a complete genomic turnover, then you must acknowledge that it is a prediction of Darwinism that there should be homologies.
If that's how you're defining "non-telic evolution," then yes. But when I say "non-telic evolution" I mean this whole non-teleological framework which says that planning and foresight was not involved in the origin of genetic diversity on earth (with the exception of human intervention).
But if you admit that Darwinian evolution can and does take place, then none of your predictions can be based on the premise that it can't and it didn't.
Therefore, you must admit that FLE permits anything that ToE permits. In which case FLE can never be more specific in its predictions than ToE.
And, in this context, what does "Darwinism" mean? Random mutation coupled to natural selection (and similar mechanisms)?
Yeah, all known mechanisms, plus common descent.
I would be the first to admit that "Darwinism" is not the best word for that, but for want of a better, I'll go with that.
1. Front-loading, by definition, involves loading the first genomes with proteins that are unnecessary for prokaryotes but are necessary for the origin of eukaryotes and multicellular life forms.
No. That is not the definition of front-loading.
Possibly I'm not being clear enough.
If you were clear enough, then I think that you yourself would reject your own ideas.
Edited by Dr Adequate, : No reason given.

This message is a reply to:
 Message 16 by Genomicus, posted 06-20-2012 1:31 PM Genomicus has replied

Replies to this message:
 Message 24 by Dr Adequate, posted 06-20-2012 2:37 PM Dr Adequate has not replied
 Message 25 by Genomicus, posted 06-20-2012 3:16 PM Dr Adequate has replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


(1)
Message 24 of 172 (665990)
06-20-2012 2:37 PM
Reply to: Message 23 by Dr Adequate
06-20-2012 2:05 PM


I sometimes find it useful to think of it as a court case, this is something concrete that we can all grasp.
You are the counsel for the prosecution.
You: If John stole the money, then the money would be missing. The money is missing. Therefore John stole the money.
Me: But that doesn't show that Tom or Dick or Harry didn't steal the money. To pin the crime definitively on John, you'd have to show that if John didn't steal the money, then the money would still be in the till.
You: But it is a matter of basic observation that the money is not in the till!
That doesn't get us anywhere. It is common ground that someone stole the money, and that it is therefore missing. But in order to pin the crime on John you have to prove that if it wasn't for John the money wouldn't be missing. Otherwise the fact that the money is missing isn't evidence against John.

This message is a reply to:
 Message 23 by Dr Adequate, posted 06-20-2012 2:05 PM Dr Adequate has not replied

  
Genomicus
Member (Idle past 1941 days)
Posts: 852
Joined: 02-15-2012


Message 25 of 172 (665996)
06-20-2012 3:16 PM
Reply to: Message 23 by Dr Adequate
06-20-2012 2:05 PM


Look, suppose you said that giraffes confirm FLE because FLE predicts giraffes.
And then I come back saying: "But is there anything in FLE that predicts that giraffes should exist? Would it not be compatible with FLE that there should be no giraffes? Where does FLE rule that out?"
And then you riposte with: "Huh? It's not FLE that rules that out, it's basic observations that rule it out."
These "basic observations", of course, being that we can see giraffes.
Don't you see that in order for a theory to predict X, it has to rule out not-X? You can't say: "My theory predicts X ... OK, I grant you it doesn't rule out not-X ... but we can see that X". Well in that case your theory hasn't made a prediction. We've just seen X.
Yes, but you're saying that FLE doesn't rule out the possibility that all essential proteins in eukaryotes will be essential in prokaryotes. I don't know how I can make this clear, but think of it like this:
The theory of common descent predicts that organisms that share a common ancestor will share the same ERV insertion spots. But does common descent rule out the possibility that ERV insertions are non-random? It does not, and therefore, using your logic, one could argue that since common descent doesn't rule out this possibility, it doesn't predict that closely related species will share the same ERV insertion sites. Do you get the idea?
But unless you claim that it is a prediction of Darwinism that there should most likely have been a complete genomic turnover, then you must acknowledge that it is a prediction of Darwinism that there should be homologies.
The non-teleological model predicts both (a) that eukaryotic proteins will share homology with prokaryotic proteins, and (b) that eukaryotic proteins will share homology with non-coding regions of prokaryotic genomes. On the other hand, FLE exclusively predicts the former.
Challenge: find a universally widespread protein among eukaryotes that has been cobbled together from different non-coding regions of prokaryotic genomes.
But if you admit that Darwinian evolution can and does take place, then none of your predictions can be based on the premise that it can't and it didn't.
Again, if by Darwinian evolution you simply mean random mutation and natural selection (and other mechanisms), then yes, of course Darwinian evolution happens. But my prediction is based on the two different models for the origin of life's diversity: the teleological, front-loading model and the non-teleological model.
Therefore, you must admit that FLE permits anything that ToE permits. In which case FLE can never be more specific in its predictions than ToE.
No, I disagree, precisely because FLE doesn't permit the LUCA's genome to consist of little more than a minimal gene set.
No. That is not the definition of front-loading.
Actually, by definition, FL does involve the loading of a genome with proteins that the basic prokaryotic cell architecture doesn't require but the eukaryotic cell plan does.

This message is a reply to:
 Message 23 by Dr Adequate, posted 06-20-2012 2:05 PM Dr Adequate has replied

Replies to this message:
 Message 27 by Dr Adequate, posted 06-20-2012 4:01 PM Genomicus has replied

  
Genomicus
Member (Idle past 1941 days)
Posts: 852
Joined: 02-15-2012


Message 26 of 172 (665997)
06-20-2012 3:24 PM
Reply to: Message 22 by PaulK
06-20-2012 2:02 PM


I'm suggesting that it is plausible that there is a set of 250 genes that would encourage the evolution of complex life.
Yes, if this set of 250 genes encoded stuff like calmodulins, histones, tubulin, dynein, etc. But such a set of genes wouldn't be something that is required by all life forms. And this is where we get our FL prediction: at minimum, the LUCA would have consisted of 250 genes (actually, fewer, given that LUCA didn't have to have a complex prokaryotic cell organization). But a minimum gene set consisting of the genes absolutely required for life doesn't allow you to front-load anything. That's why you'd need to load the genome with unnecessary - but functional - proteins.
I don't see that as very plausible, unless you assume that the LUCA was engineered.
Under the RNA world hypothesis, how did the first proteins originate? They would have originated long before the origin of the LUCA, and prior to the LUCA you'd have very simple cells (under the non-telic model) - possibly consisting of primitive membranes such as lipid bubbles - and these cells wouldn't require 250 genes.
I am not asking you to believe in the RNA world. I am saying that you have to accept it as an important part of a serious opposing position.
Absolutely. There are many problems and challenges facing the FL hypothesis. It's a shaky hypothesis at the moment.
Edited by Genomicus, : No reason given.
Edited by Genomicus, : No reason given.

This message is a reply to:
 Message 22 by PaulK, posted 06-20-2012 2:02 PM PaulK has replied

Replies to this message:
 Message 29 by PaulK, posted 06-20-2012 4:39 PM Genomicus has replied
 Message 37 by bluegenes, posted 06-21-2012 2:15 PM Genomicus has replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 27 of 172 (665999)
06-20-2012 4:01 PM
Reply to: Message 25 by Genomicus
06-20-2012 3:16 PM


Yes, but you're saying that FLE doesn't rule out the possibility that all essential proteins in eukaryotes will be essential in prokaryotes.
And I should like you to answer that point rather than another one.
The non-teleological model predicts both (a) that eukaryotic proteins will share homology with prokaryotic proteins, and (b) that eukaryotic proteins will share homology with non-coding regions of prokaryotic genomes. On the other hand, FLE exclusively predicts the former.
Where does it do that?
Again, if by Darwinian evolution you simply mean random mutation and natural selection (and other mechanisms), then yes, of course Darwinian evolution happens. But my prediction is based on the two different models for the origin of life's diversity: the teleological, front-loading model and the non-teleological model.
But so far as I can see, you believe in both.
In which case your range of predictions includes anything that Darwinism says is possible, and so cannot have greater specificity than Darwinism.
No, I disagree, precisely because FLE doesn't permit the LUCA's genome to consist of little more than a minimal gene set.
But, one more time ...
WE CAN'T SEE LUCA.
Any predictions have to be about what we can see in the present. If you admit Darwinian mechanisms, then anything that Darwinian mechanisms allow us to see in the present is allowed by your hypothesis. Which therefore cannot be more specific in its predictions than Darwinism.
Actually, by definition, FL does involve the loading of a genome with proteins that the basic prokaryotic cell architecture doesn't require but the eukaryotic cell plan does.
No. That is not part of the definition of front-loaded evolution.
Edited by Dr Adequate, : No reason given.

This message is a reply to:
 Message 25 by Genomicus, posted 06-20-2012 3:16 PM Genomicus has replied

Replies to this message:
 Message 28 by Genomicus, posted 06-20-2012 4:33 PM Dr Adequate has replied

  
Genomicus
Member (Idle past 1941 days)
Posts: 852
Joined: 02-15-2012


Message 28 of 172 (666002)
06-20-2012 4:33 PM
Reply to: Message 27 by Dr Adequate
06-20-2012 4:01 PM


And I should like you to answer that point rather than another one.
I answered your point by bringing up the example of ERVs.
Where does it do that?
*sigh*
I think I've already answered this question, but here goes:
Front-loading basically doesn't work if it must rely on some of the important eukaryotic proteins evolving purely through the chance stitching together of random DNA sequences. This is because the odds of this process generating a specified target is next to nil.
But so far as I can see, you believe in both.
Earlier, I defined what I meant by the "non-teleological model." Let me define it again for you:
By "non-teleological model" I mean the scenario wherein all of the diversity of life arose without the input of teleology at some stage in life's history. So, no, I don't accept the non-teleological model.
In which case your range of predictions includes anything that Darwinism says is possible, and so cannot have greater specificity than Darwinism.
Okay, I think I understand what you mean with this one. All FLE predictions (that I am aware of) include things that are possible under "Darwinism." However, there are some possible scenarios in Darwinian evolution that isn't allowed by FLE. And this allows us to make predictions from an FLE standpoint, predictions that Darwinian evolution does not make but predictions that can be explained by Darwinian evolution.
WE CAN'T SEE LUCA.
To which I respond that, yes, we can see LUCA, through phylogenomics and similar approaches.
I understand that this can get frustrating, since it's difficult for us to get into the mind of the other. Still, let me try yet again, using the true/false method.
True or False: You cannot front-load multicellular life forms with just a minimal genome, since there'd be no "stacking of the deck" in favor of multicellular life forms, and "stacking the deck" is the essence of front-loading.
True or False: In order to "stack the deck" in favor of multicellularity, you'd need to load the first genomes with something more than just the required minimum. You'd need to load the first genomes with proteins that would be used by multicellular life forms, allowing their origin.
True or False: Front-loading therefore predicts that the first genomes, and consequently the genome of the LUCA, had more proteins than is necessary for the existence of a cell. In other words, FL requires that the LUCA was needlessly complex.
True or False: We can detect this needless complexity by comparing the genomes of different species, allowing us to track back over deep time.
Edited by Genomicus, : No reason given.

This message is a reply to:
 Message 27 by Dr Adequate, posted 06-20-2012 4:01 PM Dr Adequate has replied

Replies to this message:
 Message 30 by Dr Adequate, posted 06-20-2012 9:44 PM Genomicus has replied

  
PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


Message 29 of 172 (666003)
06-20-2012 4:39 PM
Reply to: Message 26 by Genomicus
06-20-2012 3:24 PM


quote:
Yes, if this set of 250 genes encoded stuff like calmodulins, histones, tubulin, dynein, etc. But such a set of genes wouldn't be something that is required by all life forms
So long as it encourages the development of complex life forms, it doesn't matter what the genes code for. They need not be analogs of proteins used by known life.
quote:
And this is where we get our FL prediction: at minimum, the LUCA would have consisted of 250 genes (actually, fewer, given that LUCA didn't have to have a complex prokaryotic cell organization). But a minimum gene set consisting of the genes absolutely required for life doesn't allow you to front-load anything.
That is the very assertion that I am disagreeing with. Given 250 distinct proteins it is simply not clear that they would be insufficient for front loading, given the modest goals assumed.
quote:
Under the RNA world hypothesis, how did the first proteins originate? They would have originated long before the origin of the LUCA, and prior to the LUCA you'd have very simple cells (under the non-telic model) - possibly consisting of primitive membranes such as lipid bubbles - and these cells wouldn't require 250 genes.
My understanding is that more complex RNA life pioneered the use of proteins. And, of course, this is before the LUCA. Obviously proteins useful to this RNA life would tend to be preserved into the era of early DNA life, even if they were not absolutely essential. It seems very unlikely to me that there would be no such proteins, save for those absolutely necessary to cellular life.

This message is a reply to:
 Message 26 by Genomicus, posted 06-20-2012 3:24 PM Genomicus has replied

Replies to this message:
 Message 31 by Genomicus, posted 06-21-2012 10:48 AM PaulK has replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


(1)
Message 30 of 172 (666018)
06-20-2012 9:44 PM
Reply to: Message 28 by Genomicus
06-20-2012 4:33 PM


I answered your point by bringing up the example of ERVs.
No, that's where you ducked my point.
I think I've already answered this question, but here goes:
Front-loading basically doesn't work if it must rely on some of the important eukaryotic proteins evolving purely through the chance stitching together of random DNA sequences. This is because the odds of this process generating a specified target is next to nil.
But that is still not an answer to my question.
For example, what's to stop LUCA from having two parallel sets of genes, one for prokaryotes and one for eukaryotes?
Now, please note once more that it is not to the point to observe that this the evidence we have now shows that this didn't happen --- in order for there to be a prediction, you need to show that the very concept of FLE precludes doing it that way.
Okay, I think I understand what you mean with this one. All FLE predictions (that I am aware of) include things that are possible under "Darwinism." However, there are some possible scenarios in Darwinian evolution that isn't allowed by FLE.
Which? Mutation still happens, doesn't it? And natural selection? And lateral gene transfer? And recombination?
Anything that can happen under Darwinian mechanisms can happen under the FLE hypothesis, since it does not deny the existence of those mechanisms.
True or False: We can detect this needless complexity by comparing the genomes of different species, allowing us to track back over deep time.
False.

This message is a reply to:
 Message 28 by Genomicus, posted 06-20-2012 4:33 PM Genomicus has replied

Replies to this message:
 Message 32 by Genomicus, posted 06-21-2012 10:59 AM Dr Adequate has replied

  
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