Abiogenesis discredited

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Re: Abiogenesis discredited

#441  Postby Rumraket » Apr 13, 2012 4:17 am

asyncritus wrote:
DavidMcC wrote:Ok, here comes my "bombshell". I agree that the word, "cipher" is better than "code" for DNA base sequences, because short self-replicating RNA sequences can probably appear without a cell to control, by prebiotic chemistry, on suitable kinds of catalytic rock substrates. However, long DNA sequences did not evolve by being a "cipher in a vacuum", so to speak. They evolved as a crucial part of the cell machinery that transcribes them. This corresponds roughly to a code using the DNA sequences as input data. Thus, it is a cop-out to avoid the issue of design when creationists object that the "code must have been designed". The best atheist answer, IMO, is that, yes, it was indeed, designed - by natural selection.


Further nonsense.

The highlighted bits demonstrate that unequivocally.

by prebiotic chemistry, is that wishful thinking, fond imaginings, or what, I ask myself. And I answer, yes.

long DNA sequences did not evolve How true!

They evolved You couldn't be begging the question now, could you?

the cell machinery that transcribes them

Sir Karl Popper:

"What makes the origin of life and of the genetic code a disturbing riddle is this: the genetic code is without any biological function unless it is translated; that is, unless it leads to the synthesis of the proteins whose structure is laid down by the code.

But, as Monod points out the machinery by which the cell (at least the nonprimitive cell which is the only one we know) translates the code `consists of a least fifty macromolecular components which are themselves coded in DNA' (Monod, 1970; 1971, 143).

Thus the code cannot be translated except by using certain products of its translation. This constitutes a really baffling circle: a vicious circle, it seems for any attempt to form a model, or a theory, of the genesis of the genetic code."

Hmm. Seems we have a problem Houston.

designed - by natural selection. Is this a joke of some kind?

Already dealt with. Translation is done by RNA ribozymes(the Ribosome), by reading an RNA template (mRNA). That means translation of the code could evolve in an RNA world without the need for large complicated proteins. I guess you missed this paper:
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Re: Abiogenesis discredited

#442  Postby Rumraket » Apr 13, 2012 4:22 am

asyncritus wrote:The comparison of natural selection and mutations to the running of a genetic algorithm of some kind is pure nonsense.

The DNA sequence that codes for a functional protein exhibits the specified complexity necessary for it to code for that protein, and is therefore algorithmically incompressible, and a mathematician would therefore describe it as random. Paul Davies says: 'Can specific randomness be the guaranteed product of a deterministic, mechanical, law-like process like a primordial soup left to the mercy of the familiar laws of physics and chemistry? No it couldn't. No known law of nature could achieve this'.

He also said that: 'We conclude that biologically relevant macromolecules simultaneously possess two vital properties: randomness and extreme specificity. A chaotic process could possibly achieve the former property but would have a negligible probability of achieving the latter'.

Clearly this makes the genome an impossible object.

Should someone produce an algorithm which 'creates life', then the following objections are raised immediately:

1 What was the parallel in the primordial soup for the computer's designer?

2 What was the parallel for the algorithm's writer?

It's very obvious, isn't it, that neither was present in the primordial soup busy trying to produce the first life?

Perhaps not, to the bright sparks assembled here.

Specified complexity is a bullshit term invented by Bill Dembski, it has no proper application in the sciences. Despite Dembski's insistence that proteins contain large amounts of specified complexity, noone knows how to calculate the amount, including Dembski himself, making the assertion that some entity contains "large amounts" of it, null and void.
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Re: Abiogenesis discredited

#443  Postby DavidMcC » Apr 13, 2012 8:58 am

asyncritus wrote:Should someone produce an algorithm which 'creates life', then the following objections are raised immediately:


There was no "algorithm which creates life", only an analogy to an algorithm which plays an important part in how life EVOLVES now, post RNA-world. The "irreducibly complex code" evolved by co-evolution after the abiotic appearance of an RNA soup, because RNA-based molecules can evolve by NS, without DNA (the self-replicating RNA I posted about way back). The 35% DNA component of modern ribosomes was part of that co-evolution.

http://en.wikipedia.org/wiki/Ribosome#Description

PS, I agree with Rumraket that "specified complexity" is just a bit of nonsense made up by Dembski, presumably to sound impressive, without actually meaning anything.
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Re: Abiogenesis discredited

#444  Postby DavidMcC » Apr 13, 2012 9:00 am

... Sorry, for "35% DNA" in the above post, read "35% protein", as stated in the linked Wiki article.
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Re: Abiogenesis discredited

#445  Postby DavidMcC » Apr 13, 2012 10:07 am

For those who may be confused by my use of the phrase, "irreducible complexity" commonly associated with the creationists, Dembski and Behe, here is a short article describing a typical example of how Darwinian co-evolution produces the appearance of IC:

http://www.eurekalert.org/pub_releases/2006-04/uoo-eo040406.php

Evolution of 'irreducible complexity' explained


There are now two connotations of "IC", one that defines it as an impossible situation, and one that defines it as giving only the illusion of impossibility. I have used the latter.
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Re: Abiogenesis discredited

#446  Postby hackenslash » Apr 13, 2012 11:06 am

Just A Theory wrote:
asyncritus wrote:The comparison of natural selection and mutations to the running of a genetic algorithm of some kind is pure nonsense.


I wouldn't go so far as 'pure nonsense' but there are some major differences. Let's see where you go with this...

The DNA sequence that codes for a functional protein exhibits the specified complexity necessary for it to code for that protein, and is therefore algorithmically incompressible, and a mathematician would therefore describe it as random.


Oh, you went there :doh:

Firstly, the term "specified complexity" is an oxymoron. In terms of information theory (specifically algorithmic information theory), complexity is a measure of the information content of a message and is proportional to the length of the program which would fully describe the message when running on a universal Turing machine. It's not strictly a measure of randomness but thinking along those lines will not lead you far astray.

Now 'specification' refers to reducing uncertainty in the information string. High specificity means that the next bit of the message is predictable from what has gone before whilst low specificity means the opposite. Again, there is a link to randomness but it can be easily seen that 'specification' and 'complexity' are actually almost diametrically opposite in meaning. Therefore the term specified complexity is just word salad.

Second, the translation of DNA into proteins is absolutely not algorithmically incompressible due to redundancy in the third nucleotide of virtually every triplet codon. GCT is functionally the same as GCC, in fact there are 64 possible codons and only 20 amino acids plus 3 stop sequences meaning that there is a large amount of redundancy in the genetic code. It is therefore trivially easy to compress the genetic code by removing some of that redundancy.

Finally, a mathematician would not describe the entire process as random because there are clear predictive elements when viewing protein primary and tertiary structure. It is possible to identify hydrophobic/hydrophilic regions of proteins, active sites, alpha helices and beta pleated sheets, all of which display non-random arrangements of amino acids.

Basically, the only correct words in your sentence above were the prepositiions.

Paul Davies says: 'Can specific randomness be the guaranteed product of a deterministic, mechanical, law-like process like a primordial soup left to the mercy of the familiar laws of physics and chemistry? No it couldn't. No known law of nature could achieve this'.

He also said that: 'We conclude that biologically relevant macromolecules simultaneously possess two vital properties: randomness and extreme specificity. A chaotic process could possibly achieve the former property but would have a negligible probability of achieving the latter'.


Paul Davies - you mean the theistic scientist and poster child of the Templeton Foundation who claims that the immutability of physical laws has a basis in Christian theology. Pardon me whilst I chortle in mirth that you would quote this guy in support of a scientific proposition. In fact, let me give you another quote from the estimable Prof Davies:

I had the advantage of being unencumbered by knowledge. I dropped chemistry at the age of 16, and all I knew about arsenic came from Agatha Christie novels

Clearly this makes the genome an impossible object.


Clearly you (and Paul) are peddling doctrine from an orifice more commonly associated with the elimination of waste.

Should someone produce an algorithm which 'creates life', then the following objections are raised immediately:

1 What was the parallel in the primordial soup for the computer's designer?

2 What was the parallel for the algorithm's writer?

It's very obvious, isn't it, that neither was present in the primordial soup busy trying to produce the first life?

Perhaps not, to the bright sparks assembled here.


And yet abiogenesis induitably occurred...


Another post by JAT that will go down as a classic. Lovely dissection.

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Re: Abiogenesis discredited

#447  Postby Shrunk » Apr 13, 2012 2:20 pm

Rumraket wrote: Specified complexity is a bullshit term invented by Bill Dembski, it has no proper application in the sciences. Despite Dembski's insistence that proteins contain large amounts of specified complexity, noone knows how to calculate the amount, including Dembski himself, making the assertion that some entity contains "large amounts" of it, null and void.


I'll also remind everyone of this discussion from the blog the Dembski himself created, in which members were asked to demonstrate how CSI could be calculated for a series of real world scenarios. No one could, at least not in such a way that did not show that whatever CSI might be, it could easily be generated by common evolutionary processes. Maybe asyncritus could give answering the questions a try.
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Re: Abiogenesis discredited

#448  Postby DanDare » Apr 15, 2012 8:56 am

DavidMcC wrote:
campermon wrote:The random mutations introduced into each generation provide novel patterns for the genetic algorithm to act upon. More 'grist for the mill'.

No, surely it is the variation that matters. Randomness is only the way it happens in biological evolution. In engineering, you can just as well get your mutational differences (from which to select) on a systematic basis.

No randomness is not optional. To systematically apply variations would require that you already know the optimal design. The only alternative to random variation is a brute force run through every possible combination. Combinatorial theory shows that the universe may not be around long enough to do that for even moderately complex systems.
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Re: Abiogenesis discredited

#449  Postby DavidMcC » Apr 15, 2012 11:13 am

DanDare wrote:
No randomness is not optional. To systematically apply variations would require that you already know the optimal design. The only alternative to random variation is a brute force run through every possible combination. Combinatorial theory shows that the universe may not be around long enough to do that for even moderately complex systems.


Yes, it is, because the only difference between systematic coarse scans and random ones is the exact size of the interval. Like campermon, you seem to forget that combination of a coarse systematic scan be followed by a fine scan around the best regions, without creating a massive combinatorial problem. Using random intervals is like gambling, because you're hoping for a "lucky strike".
Having said that, this particular subject is a bit of a detour in this thread, so there is little point in pursuing it here.
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Re: Abiogenesis discredited

#450  Postby asyncritus » Apr 15, 2012 10:33 pm

Sir Karl Popper:

"What makes the origin of life and of the genetic code a disturbing riddle is this: the genetic code is without any biological function unless it is translated; that is, unless it leads to the synthesis of the proteins whose structure is laid down by the code.

But, as Monod points out the machinery by which the cell (at least the nonprimitive cell which is the only one we know) translates the code `consists of a least fifty macromolecular components which are themselves coded in DNA' (Monod, 1970; 1971, 143).

Thus the code cannot be translated except by using certain products of its translation. This constitutes a really baffling circle: a vicious circle, it seems for any attempt to form a model, or a theory, of the genesis of the genetic code."

Hmm. Seems we have a problem Houston.

designed - by natural selection. Is this a joke of some kind?


Already dealt with. Translation is done by RNA ribozymes(the Ribosome), by reading an RNA template (mRNA).


Guess you didn't pay any attention to this:

But, as Monod points out the machinery by which the cell (at least the nonprimitive cell which is the only one we know) translates the code `consists of a least fifty macromolecular components which are themselves coded in DNA' (Monod, 1970; 1971, 143).

You make it sound so idiotically simple. Yet both Monod and Popper disagree with you. How do you account for that disagreement?

Thus the code cannot be translated except by using certain products of its translation. This constitutes a really baffling circle: a vicious circle, it seems for any attempt to form a model, or a theory, of the genesis of the genetic code."


That means translation of the code could evolve in an RNA world without the need for large complicated proteins.


Monod says 'at least fifty macromolecular components'. Whether he meant proteins or not, it unclear.

But the probability of 50 macromolecular components, being there at the right time, with all the other cellular machinery required, is prettly small, wouldn't you say? I would say impossible.

But rumraket wants a calculation of specified complexity. Can you provide a calculation of the probability of the process you wishfully describe so airily?

I recognise nonsense when I see it. Tough luck.
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Re: Abiogenesis discredited

#451  Postby Just A Theory » Apr 15, 2012 11:20 pm

asyncritus wrote:
Guess you didn't pay any attention to this:

But, as Monod points out the machinery by which the cell (at least the nonprimitive cell which is the only one we know) translates the code `consists of a least fifty macromolecular components which are themselves coded in DNA' (Monod, 1970; 1971, 143).

You make it sound so idiotically simple. Yet both Monod and Popper disagree with you. How do you account for that disagreement?


And you, in turn, did not pay attention to my post here.

While the concept of RNA as a precursor to the DNA/protein system has its roots in Woese (you may have heard of him, he's the guy who elucidated the concept of the 3 Domains of life), RNA world as a fully fleshed out hypothesis was not in common usage until after 1986. That's 15 years after Monod published his work and 26 years before today. As I mentioned in my post, you're four decades off the pace.

As DavidMcc suggested, RNA can act as both template and enzyme. All proteins are transcribed from mRNA templates which is proof of concept that RNA could have been a template for any postulated macromolecular component. Monod didn't know this because he published his book 15 years before the concept came into vogue.

What you are doing here is like someone using Newton to refute Einstein. You are citing outdated sources in an attempt to refute science published after those sources - it is a prime example of poor scholarship and one that would get you severely reprimanded in any reputable academic institution. Stop it.

Monod says 'at least fifty macromolecular components'. Whether he meant proteins or not, it unclear.

But the probability of 50 macromolecular components, being there at the right time, with all the other cellular machinery required, is prettly small, wouldn't you say? I would say impossible.


Please go read up on RNA world concept before you embarrass yourself further.

But rumraket wants a calculation of specified complexity. Can you provide a calculation of the probability of the process you wishfully describe so airily?

I recognise nonsense when I see it. Tough luck.


Did you miss my other post here?

Specified complexity is an oxymoron and cannot be defined even by its proponents.
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Re: Abiogenesis discredited

#452  Postby CharlieM » Apr 16, 2012 12:08 am

Just A Theory wrote:
Second, the translation of DNA into proteins is absolutely not algorithmically incompressible due to redundancy in the third nucleotide of virtually every triplet codon. GCT is functionally the same as GCC, in fact there are 64 possible codons and only 20 amino acids plus 3 stop sequences meaning that there is a large amount of redundancy in the genetic code. It is therefore trivially easy to compress the genetic code by removing some of that redundancy.


http://www.sciencedaily.com/releases/2012/03/120328142850.htm
By measuring the rate of protein production in bacteria, the team discovered that slight genetic alterations could have a dramatic effect. This was true even for seemingly insignificant genetic changes known as "silent mutations," which swap out a single DNA letter without changing the ultimate gene product. To their surprise, the scientists found these changes can slow the protein production process to one-tenth of its normal speed or less.

As described March 28 in the journal Nature, the speed change is caused by information contained in what are known as redundant codons -- small pieces of DNA that form part of the genetic code. They were called "redundant" because they were previously thought to contain duplicative rather than unique instructions.

This new discovery challenges half a century of fundamental assumptions in biology. It may also help speed up the industrial production of proteins, which is crucial for making biofuels and biological drugs used to treat many common diseases, ranging from diabetes to cancer.

"The genetic code has been thought to be redundant, but redundant codons are clearly not identical," said Jonathan Weissman, PhD, a Howard Hughes Medical Institute Investigator in the UCSF School of Medicine Department of Cellular and Molecular Pharmacology.

"We didn't understand much about the rules," he added, but the new work suggests nature selects among redundant codons based on genetic speed as well as genetic meaning.


So the redundancy of codons is an assumption based on ignorance that has been treated as fact with very little skepticism in evidence.
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Re: Abiogenesis discredited

#453  Postby Shrunk » Apr 16, 2012 12:51 am

asyncritus wrote:But rumraket wants a calculation of specified complexity.


Actually, I'd like that do. It should be possible since the creationist mathematician William Dembski devised the term to denote something that should be calculable, and only present in something that has been designed by an intelligent being. Yet no one who believes in it seems able to calculate except in such a way that shows it can be generated by known naturalistic processes. So Maybe you're the one person who can actually calculate it. If not, you should stop throwing the term around as if it is anything but meaningless nonsense.
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Re: Abiogenesis discredited

#454  Postby Just A Theory » Apr 16, 2012 1:17 am

CharlieM wrote:
Just A Theory wrote:
Second, the translation of DNA into proteins is absolutely not algorithmically incompressible due to redundancy in the third nucleotide of virtually every triplet codon. GCT is functionally the same as GCC, in fact there are 64 possible codons and only 20 amino acids plus 3 stop sequences meaning that there is a large amount of redundancy in the genetic code. It is therefore trivially easy to compress the genetic code by removing some of that redundancy.


http://www.sciencedaily.com/releases/2012/03/120328142850.htm
By measuring the rate of protein production in bacteria, the team discovered that slight genetic alterations could have a dramatic effect. This was true even for seemingly insignificant genetic changes known as "silent mutations," which swap out a single DNA letter without changing the ultimate gene product. To their surprise, the scientists found these changes can slow the protein production process to one-tenth of its normal speed or less.

As described March 28 in the journal Nature, the speed change is caused by information contained in what are known as redundant codons -- small pieces of DNA that form part of the genetic code. They were called "redundant" because they were previously thought to contain duplicative rather than unique instructions.

This new discovery challenges half a century of fundamental assumptions in biology. It may also help speed up the industrial production of proteins, which is crucial for making biofuels and biological drugs used to treat many common diseases, ranging from diabetes to cancer.

"The genetic code has been thought to be redundant, but redundant codons are clearly not identical," said Jonathan Weissman, PhD, a Howard Hughes Medical Institute Investigator in the UCSF School of Medicine Department of Cellular and Molecular Pharmacology.

"We didn't understand much about the rules," he added, but the new work suggests nature selects among redundant codons based on genetic speed as well as genetic meaning.


So the redundancy of codons is an assumption based on ignorance that has been treated as fact with very little skepticism in evidence.


Happy to discuss via PM but the linked article does not contradict what I was saying. The postulation that different triplet codons may be transcribed at different rates isn't that shocking to me considering the differing bond strengths of the G+C vs A+T pairings - you have to take that into account when designing oligos for use in PCR.

It's great work by the researchers to quantify the effect but the redundancy of the genetic code in terms of what amino acids are coded for still remains in play. However, in bacteria which typically have more than one ORF per chromosome, then the redundancy may disappear due to re-use of codons.

The original assertion was that genetic sequences (of DNA) are algorithmically incompressible. Even if there is a differential rate of transcription between codons, the assertion of incompressibility is still false.
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Re: Abiogenesis discredited

#455  Postby Rumraket » Apr 16, 2012 4:11 am

asyncritus wrote:
Sir Karl Popper:

"What makes the origin of life and of the genetic code a disturbing riddle is this: the genetic code is without any biological function unless it is translated; that is, unless it leads to the synthesis of the proteins whose structure is laid down by the code.

But, as Monod points out the machinery by which the cell (at least the nonprimitive cell which is the only one we know) translates the code `consists of a least fifty macromolecular components which are themselves coded in DNA' (Monod, 1970; 1971, 143).

Thus the code cannot be translated except by using certain products of its translation. This constitutes a really baffling circle: a vicious circle, it seems for any attempt to form a model, or a theory, of the genesis of the genetic code."

Hmm. Seems we have a problem Houston.

designed - by natural selection. Is this a joke of some kind?


Already dealt with. Translation is done by RNA ribozymes(the Ribosome), by reading an RNA template (mRNA).


Guess you didn't pay any attention to this:

But, as Monod points out the machinery by which the cell (at least the nonprimitive cell which is the only one we know) translates the code `consists of a least fifty macromolecular components which are themselves coded in DNA' (Monod, 1970; 1971, 143).

You make it sound so idiotically simple. Yet both Monod and Popper disagree with you. How do you account for that disagreement?

Thus the code cannot be translated except by using certain products of its translation. This constitutes a really baffling circle: a vicious circle, it seems for any attempt to form a model, or a theory, of the genesis of the genetic code."


That means translation of the code could evolve in an RNA world without the need for large complicated proteins.


Monod says 'at least fifty macromolecular components'. Whether he meant proteins or not, it unclear.

But the probability of 50 macromolecular components, being there at the right time, with all the other cellular machinery required, is prettly small, wouldn't you say? I would say impossible.

But rumraket wants a calculation of specified complexity. Can you provide a calculation of the probability of the process you wishfully describe so airily?

I recognise nonsense when I see it. Tough luck.

You're not the first creationist to throw quotemines from 1975 at me. You really should try and catch up with the science, though, because you're 37 years behind, at least.

And don't even get me started on your "warm little pond" nonsense. When's that quote from, exactly...? 1859 ? :lol:
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Re: Abiogenesis discredited

#456  Postby Rumraket » Apr 16, 2012 4:18 am

CharlieM wrote:
Just A Theory wrote:
Second, the translation of DNA into proteins is absolutely not algorithmically incompressible due to redundancy in the third nucleotide of virtually every triplet codon. GCT is functionally the same as GCC, in fact there are 64 possible codons and only 20 amino acids plus 3 stop sequences meaning that there is a large amount of redundancy in the genetic code. It is therefore trivially easy to compress the genetic code by removing some of that redundancy.


http://www.sciencedaily.com/releases/2012/03/120328142850.htm
By measuring the rate of protein production in bacteria, the team discovered that slight genetic alterations could have a dramatic effect. This was true even for seemingly insignificant genetic changes known as "silent mutations," which swap out a single DNA letter without changing the ultimate gene product. To their surprise, the scientists found these changes can slow the protein production process to one-tenth of its normal speed or less.

As described March 28 in the journal Nature, the speed change is caused by information contained in what are known as redundant codons -- small pieces of DNA that form part of the genetic code. They were called "redundant" because they were previously thought to contain duplicative rather than unique instructions.

This new discovery challenges half a century of fundamental assumptions in biology. It may also help speed up the industrial production of proteins, which is crucial for making biofuels and biological drugs used to treat many common diseases, ranging from diabetes to cancer.

"The genetic code has been thought to be redundant, but redundant codons are clearly not identical," said Jonathan Weissman, PhD, a Howard Hughes Medical Institute Investigator in the UCSF School of Medicine Department of Cellular and Molecular Pharmacology.

"We didn't understand much about the rules," he added, but the new work suggests nature selects among redundant codons based on genetic speed as well as genetic meaning.


So the redundancy of codons is an assumption based on ignorance that has been treated as fact with very little skepticism in evidence.

Irrelevant post of the day. Do you know what is understood by code redundancy? It's an interesting article in many ways, and opens up a whole new area of thoughts one can make on the nature of the code, but there are still 4 codons for an amino acid, even if the different codons have an impact on translation speeds.

The code is known to be highly robust against mistranslations, meaning there's an extremely high chance that, even with an accidental substitution during replication (textbook case of point-mutation), the resulting codon-change won't result in an amino acid change. Furthermore, during actual translation of the mRNA transcript, a non-heritable "mutation" can arise from misreads done by the Ribosome. Again, the codon redundancy (four for every one amino acid) manifests itself by ensuring the correct amino acid is picked.
It's even better than this however, when we move beyond mere codon redundancy, and take a look at the chemical and physical properties, ex. polarity of the corresponding amino acids to their cognate codons. Should a heritable substitution resulting in protein sequence change, or a misread during translation, actually still happen, the code is also arranged in such a way that codons that code for amino acids with similar properties have more similar codons.

Now, before we start ejaculating all over ourselves and each other with how incredibly intelligent and miraculous we think the code is, we should start by taking a cold shower and realize the code can still be improved, and isn't actually the best possible one. And furthermore that, there are a number of biochemical reasons for why at least some of the code has the structure it does, which means they aren't pure accidental evolution, nor supervising ID-designer foresight, but the result of selection constrained by physico-chemical nessecity. One rather large suprise to researchers working on the code's evolution was the finding that codes with significantly superior robustness and redundancy against mistranslations, are found, from an evolutionary perspective, relatively few selective steps away from the extant code, on a fitness landscape of robustness against mistranslation. That means the code could be significantly improved with 15-20% reduction in errors, by rearranging the codons in a few places. One wonders why a supremely intelligent, supernatural designer wouldn't do this. However, if one looks at the code from an evolutionary perspective, it's current structure seems to have frozen in place at a time when it's usage had become ubiquitous, and further modifications to it would have required significant losses of biochemistry that would have become fundamentally important to the pertinent organisms.
In that respect, the code is still regarded by many as a "frozen accident", in that the code has stopped evolving towards what are obviously significantly superior codes, because the code's job is now so fundamentally ingrained in the fundamental metabolism of all living organisms. Evolution has no foresight, and it cannot "go back" and start from an earlier step in code-evolution to reach a new and even better code. As with all other evolving things in nature, it's left to modify what's already there.
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Re: Abiogenesis discredited

#457  Postby rainbow » Apr 16, 2012 9:42 am

Just A Theory wrote:And yet abiogenesis induitably occurred...


How?
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Re: Abiogenesis discredited

#458  Postby Rumraket » Apr 16, 2012 9:57 am

rainbow wrote:
Just A Theory wrote:And yet abiogenesis induitably occurred...


How?

We don't know, and when we're speaking of Abiogenesis here on earth, the way it actually happened, we may never know with any great deal of certainty. The best we can do is suggest ways in which it could have happened, and try to demonstrate how by performing experiments and correlate them with what we know about conditions that were extant on the early earth.

I have to ask you, though, rainbow, what the point is with that question? Because given the innumerable times we've been over this subject, you must know this by now. So I'm a bit puzzled why you keep returning with the same question? If you wish to imply that, since we don't know in any detail how it happened, that we can't say for certain that it happened, I can demonstrate the fallacy of that silly piece of logic with a bit of mathematics. Here's how:

I don't know what the square root of 35 is(how life began), but I know 35 has a square root(that it began), and I know it's not 5(goddidit).

QED.

Have a nice day.
"When inventing a god, the most important thing is to claim it is invisible, inaudible and imperceptible in every way. Otherwise, people will become skeptical when it appears to no one, is silent and does nothing." - Anonymous
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Re: Abiogenesis discredited

#459  Postby GrahamH » Apr 16, 2012 10:10 am

asyncritus wrote:The comparison of natural selection and mutations to the running of a genetic algorithm of some kind is pure nonsense.


Not at all. An algorithm is a sequence of basic operations. The nature of the operations could be anything, such as assembling proteins, duplicating strands of DNA or killing a cell that can't metabolise available energy sources.
The genetic algorithm is simply:

Add small random variation to pattern (mutate and/or mix)
Test fitness effect of pattern (does the pattern support itself?)
Duplicate/persist pattern (e.g. stay alive to reproduce)
Repeat

That is an algorithm describing evolutionary processes.

That algorithm can be 'run' with chemicals, with structures, in software, in human design, in brains, literally anywhere a pattern can persist with small variation through multiple 'fitness tests'. Passing a 'fitness test' means greater prevalence of the pattern. Failing a 'fitness test' means the pattern is less prevalent.
Why do you think that?
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Re: Abiogenesis discredited

#460  Postby CharlieM » Apr 16, 2012 10:16 am

Just A Theory wrote:
The original assertion was that genetic sequences (of DNA) are algorithmically incompressible. Even if there is a differential rate of transcription between codons, the assertion of incompressibility is still false.


Are you saying that you could insert any equivalent codons (ie GCT for GCC) into the germ cell of an organism and still end up with a viable adult? Do you think that the timing of protein production is of little or no consequence? For example, would it matter if one protein sub-unit was produced ten times slower than its partner sub-units? An organism is an organized entity, organized in space and in time. And if you are arguing only about isolated DNA sequences then you are arguing about abstractions, not about life.
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