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Probability of evolution

Probability of evolution

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Originally posted by telerion
Even worse that he is not right. I really can't wait for him to stroll back through here and try to defend his source.
jeeze how many times is that pseudo science gonna be shown.
the "cereatioists" think the following is invalid because Hardison had required a particular outcome , of course he did ,, he assumed there was a chain that was being built by the letters':

the probility of it occuring according to dj's type of probability would be 26 ^13 which is pretty unlikely to happen anytime soon ,, however the test did assume that the sequencial steps once made ,,remained and the program moved on the the next ,
which incidently does mimic chemical reactions for more closely thean requiring the already bonded chemicls yo "unbond" and return to the pool.

this 1984 program by Richard Harsison on average produced the sequence "tobeornottobe" is 338 seconds

THE COMPUTER PROGRAM IN APPENDIX E IN "UPON THE SHOULDERS OF GIANTS" BY
RICHARD HARDISON

10 REM 1984 R. HARDISON
11 PRINT "RANDOMIZING ALPHABET"
12 PRINT "WRITE HAMLET, KEEPING"
13 PRINT "SUCCESSES."
14 PRINT :; REM N-COUNTER: # OF TRIALS
15 REM T=COUNTER:REUSE "TO BE"
16 PRINT "SUBROUTINE TO
17 PRINT "RANDOMIZE AND SELECT"
18 PRINT "LETTER"
30 N = 0
40 FOR G = 1 TO 10
50 T = 0
60 GOTO 80
70 X = INT (26 * RND (1)) + 1: RETURN
80 GOSUB 70
90 N = N + 1
100 IF X = 20 THEN PRINT "T": IF X = 20 THEN GOTO 120
110 GOTO 60
120 N = N + 1
130 GOSUB 70
140 IF X = 15 THEN PRINT "O": IF X = 15 THEN PRINT : IF X = 15 THEN GOTO 160
150 GOTO 120 160 N = N + 1 170 GOSUB 70 180 IF X = 2 THEN PRINT "B": IF X = 2
THEN GOTO 200 190 GOTO 160 200 N = N + 1 210 GOSUB 70 220 IF X = 5 THEN PRINT
"E": IF X = 5 THEN PRINT : IF X = 5 THEN GOTO 240 230 GOTO 200 240 T = T + 1
250 IF T = 2 THEN GOTO 460 260 N = N + 1 270 GOSUB 70 280 IF X = 15 THEN
PRINT
"O": IF X = 15 THEN GOTO 300 290 GOTO 260 300 N = N + 1 310 GOSUB 70 320 IF X
= 18 THEN PRINT "R": IF X = 18 THEN GOTO 340 330 GOTO 300 340 N = N + 1 350
GOSUB 70 360 IF X = 14 THEN PRINT "N": IF X = 14 THEN GOTO 380 370 GOTO 340
380 N = N + 1 390 GOSUB 70 400 IF X = 15 THEN PRINT "O": IF X = 15 THEN GOTO
420 410 GOTO 380 420 N = N + 1 430 GOSUB 70 440 IF X = 20 THEN PRINT "T": IF
X
= 20 THEN PRINT : IF X = 20 THEN GOTO 60 450 GOTO 420 460 PRINT "N=";N;" KEYS
PRESSED TO WRITE 'TO BE OR NOT TO BE'" 470 PRINT "FOR";G;" RUN(S) OF PROGRAM"
480 PRINT 490 NEXT G 500 END 510 REM IF THE PROGRAM WERE 511 REM WRITTEN TO
INCLUDE 512 REM PUNCTUATION MARKS ETC. 513 REM THE PROGRAM WOULD 514 REM
TAKE LONGER, BUT WOULD 515 REM STILL NOT BE PROHIBI- 516 REM TIVE 517 PRINT
518 PRINT "WITH 3000 RUNS, THE MEAN" 519 PRINT "# of trials=333" 520 PRINT
"THE MEAN TIME REQUIRED" 521 PRINT "WAS .14 MINUTES TO PRINT" 522 PRINT
"TOBEORNOTTOBE" ------------------------------- From this analysis of Darwin,




AThousandYoung
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Originally posted by flyUnity
Im suprised that you and LemonJello refute that DNA dont evolve, Evolutionist claim that DNA came from RNA, I never heard of any scientist say that DNA evolves, as a matter of fact, thats one purpose of DNA, to keep offspring like the parent.

I may be wrong, I just never heard of any scientist say that DNA evolved
I am a scientist. DNA has evolved.

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Originally posted by flyUnity
Im suprised that you and LemonJello refute that DNA dont evolve, Evolutionist claim that DNA came from RNA, I never heard of any scientist say that DNA evolves, as a matter of fact, thats one purpose of DNA, to keep offspring like the parent.

I may be wrong, I just never heard of any scientist say that DNA evolved
Its a facile argument. DNA is DNA and always is DNA. What does vary is the structure of DNA (eukaryotes vs. prokaryotes) and highly structured nuclear DNA is common to 'higher' plants and animals. The order in which bases occur within DNA also varies; recombination does not change (or evolve) the DNA but reshuffles it into new combinations, novel DNA is generated by point mutations, indels and copying errors. As fU, DNA passes genetic information from parents to progeny, and genic regions are highly conserved. Other region however, are highly variable.

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Originally posted by AThousandYoung
I am a scientist. DNA has evolved.
How feasibile is the proposition that Earth's Carbon,Nitrogen and Oxygen were produced in the same supernova and had been forming organic compounds before the Earth formed ? Giving the process a jump start.

AThousandYoung
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Introduction
Every so often, someone comes up with the statement "the formation of any enzyme by chance is nearly impossible, therefore abiogenesis is impossible". Often they cite an impressive looking calculation from the astrophysicist Fred Hoyle, or trot out something called "Borel's Law" to prove that life is statistically impossible. These people, including Fred, have committed one or more of the following errors...

...1) They calculate the probability of the formation of a "modern" protein, or even a complete bacterium with all "modern" proteins, by random events. This is not the abiogenesis theory at all.

2) They assume that there is a fixed number of proteins, with fixed sequences for each protein, that are required for life.

3) They calculate the probability of sequential trials, rather than simultaneous trials.

4) They misunderstand what is meant by a probability calculation.

5) They seriously underestimate the number of functional enzymes/ribozymes present in a group of random sequences.

I will try and walk people through these various errors, and show why it is not possible to do a "probability of abiogenesis" calculation in any meaningful way.

A primordial protoplasmic globule
So the calculation goes that the probability of forming a given 300 amino acid long protein (say an enzyme like carboxypeptidase) randomly is (1/20)300 or 1 chance in 2.04 x 10390, which is astoundingly, mind-beggaringly improbable. This is then cranked up by adding on the probabilities of generating 400 or so similar enzymes until a figure is reached that is so huge that merely contemplating it causes your brain to dribble out your ears. This gives the impression that the formation of even the smallest organism seems totally impossible. However, this is completely incorrect.

Firstly, the formation of biological polymers from monomers is a function of the laws of chemistry and biochemistry, and these are decidedly not random.

Secondly, the entire premise is incorrect to start off with, because in modern abiogenesis theories the first "living things" would be much simpler, not even a protobacteria, or a preprotobacteria (what Oparin called a protobiont [8] and Woese calls a progenote [4]), but one or more simple molecules probably not more than 30-40 subunits long. These simple molecules then slowly evolved into more cooperative self-replicating systems, then finally into simple organisms [2, 5, 10, 15, 28]. An illustration comparing a hypothetical protobiont and a modern bacteria is given below.

The first "living things" could have been a single self replicating molecule, similar to the "self-replicating" peptide from the Ghadiri group [7, 17], or the self replicating hexanucleotide [10], or possibly an RNA polymerase that acts on itself [12].

Another view is the first self-replicators were groups of catalysts, either protein enzymes or RNA ribozymes, that regenerated themselves as a catalytic cycle [3, 5, 15, 26, 28]. An example is the SunY three subunit self-replicator [24]. These catalytic cycles could be limited in a small pond or lagoon, or be a catalytic complex adsorbed to either clay or lipid material on clay. Given that there are many catalytic sequences in a group of random peptides or polynucleotides (see below) it's not unlikely that a small catalytic complex could be formed.

These two models are not mutually exclusive. The Ghadiri peptide can mutate and form catalytic cycles [9].

No matter whether the first self-replicators were single molecules, or complexes of small molecules, this model is nothing like Hoyle's "tornado in a junkyard making a 747". Just to hammer this home, here is a simple comparison of the theory criticised by creationists, and the actual theory of abiogenesis.

Note that the real theory has a number of small steps, and in fact I've left out some steps (especially between the hypercycle-protobiont stage) for simplicity. Each step is associated with a small increase in organisation and complexity, and the chemicals slowly climb towards organism-hood, rather than making one big leap [4, 10, 15, 28].

Where the creationist idea that modern organisms form spontaneously comes from is not certain. The first modern abiogenesis formulation, the Oparin/Haldane hypothesis from the 20's, starts with simple proteins/proteinoids developing slowly into cells. Even the ideas circulating in the 1850's were not "spontaneous" theories. The nearest I can come to is Lamarck's original ideas from 1803! [8]

Given that the creationists are criticising a theory over 150 years out of date, and held by no modern evolutionary biologist, why go further? Because there are some fundamental problems in statistics and biochemistry that turn up in these mistaken "refutations".

The myth of the "life sequence"
Another claim often heard is that there is a "life sequence" of 400 proteins, and that the amino acid sequences of these proteins cannot be changed, for organisms to be alive.

This, however, is nonsense. The 400 protein claim seems to come from the protein coding genome of Mycobacterium genetalium, which has the smallest genome currently known of any modern organism [20]. However, inspection of the genome suggests that this could be reduced further to a minimal gene set of 256 proteins [20]. Note again that this is a modern organism. The first protobiont/progenote would have been smaller still [4], and preceded by even simpler chemical systems [3, 10, 11, 15].

As to the claim that the sequences of proteins cannot be changed, again this is nonsense. There are in most proteins regions where almost any amino acid can be substituted, and other regions where conservative substitutions (where charged amino acids can be swapped with other charged amino acids, neutral for other neutral amino acids and hydrophobic amino acids for other hydrophobic amino acids) can be made. Some functionally equivalent molecules can have between 30 - 50% of their amino acids different. In fact it is possible to substitute structurally non-identical bacterial proteins for yeast proteins, and worm proteins for human proteins, and the organisms live quite happily.

The "life sequence" is a myth.

Coin tossing for beginners and macromolecular assembly
So let's play the creationist game and look at forming a peptide by random addition of amino acids. This certainly is not the way peptides formed on the early Earth, but it will be instructive.

I will use as an example the "self-replicating" peptide from the Ghadiri group mentioned above [7]. I could use other examples, such as the hexanucleotide self-replicator [10], the SunY self-replicator [24] or the RNA polymerase described by the Eckland group [12], but for historical continuity with creationist claims a small peptide is ideal. This peptide is 32 amino acids long with a sequence of RMKQLEEKVYELLSKVACLEYEVARLKKVGE and is an enzyme, a peptide ligase that makes a copy of itself from two 16 amino acid long subunits. It is also of a size and composition that is ideally suited to be formed by abiotic peptide synthesis. The fact that it is a self replicator is an added irony.

The probability of generating this in successive random trials is (1/20)32 or 1 chance in 4.29 x 1040. This is much, much more probable than the 1 in 2.04 x 10390 of the standard creationist "generating carboxypeptidase by chance" scenario, but still seems absurdly low.

However, there is another side to these probability estimates, and it hinges on the fact that most of us don't have a feeling for statistics. When someone tells us that some event has a one in a million chance of occuring, many of us expect that one million trials must be undergone before the said event turns up, but this is wrong.

Here is a experiment you can do yourself: take a coin, flip it four times, write down the results, and then do it again. How many times would you think you had to repeat this procedure (trial) before you get 4 heads in a row?

Now the probability of 4 heads in a row is is (1/2)4 or 1 chance in 16: do we have to do 16 trials to get 4 heads (HHHH)? No, in successive experiments I got 11, 10, 6, 16, 1, 5, and 3 trials before HHHH turned up. The figure 1 in 16 (or 1 in a million or 1 in 1040) gives the likelihood of an event in a given trial, but doesn't say where it will occur in a series. You can flip HHHH on your very first trial (I did). Even at 1 chance in 4.29 x 1040, a self-replicator could have turned up surprisingly early. But there is more.

1 chance in 4.29 x 1040 is still orgulously, gobsmackingly unlikely; it's hard to cope with this number. Even with the argument above (you could get it on your very first trial) most people would say "surely it would still take more time than the Earth existed to make this replicator by random methods". Not really; in the above examples we were examining sequential trials, as if there was only one protein/DNA/proto-replicator being assembled per trial. In fact there would be billions of simultaneous trials as the billions of building block molecules interacted in the oceans, or on the thousands of kilometers of shorelines that could provide catalytic surfaces or templates [2,15].

Let's go back to our example with the coins. Say it takes a minute to toss the coins 4 times; to generate HHHH would take on average 8 minutes. Now get 16 friends, each with a coin, to all flip the coin simultaneously 4 times; the average time to generate HHHH is now 1 minute. Now try to flip 6 heads in a row; this has a probability of (1/2)6 or 1 in 64. This would take half an hour on average, but go out and recruit 64 people, and you can flip it in a minute. If you want to flip a sequence with a chance of 1 in a billion, just recruit the population of China to flip coins for you, you will have that sequence in no time flat.

(continued)

AThousandYoung
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Originally posted by AThousandYoung
Introduction
Every so often, someone comes up with the statement "the formation of any enzyme by chance is nearly impossible, therefore abiogenesis is impossible". Often they cite an impressive looking calculation from the astroph ...[text shortened]... So, if on our prebiotic earth we have a billion peptides growing s
So, if on our prebiotic earth we have a billion peptides growing simultaneously, that reduces the time taken to generate our replicator significantly.

Okay, you are looking at that number again, 1 chance in 4.29 x 1040, that's a big number, and although a billion starting molecules is a lot of molecules, could we ever get enough molecules to randomly assemble our first replicator in under half a billion years?

Yes, one kilogram of the amino acid arginine has 2.85 x 1024 molecules in it (that's well over a billion billion); a tonne of arginine has 2.85 x 1027 molecules. If you took a semi-trailer load of each amino acid and dumped it into a medium size lake, you would have enough molecules to generate our particular replicator in a few tens of years, given that you can make 55 amino acid long proteins in 1 to 2 weeks [14,16].

So how does this shape up with the prebiotic Earth? On the early Earth it is likely that the ocean had a volume of 1 x 1024 litres. Given an amino acid concentration of 1 x 10-6 M (a moderately dilute soup, see Chyba and Sagan 1992 [23]), then there are roughly 1 x 1050 potential starting chains, so that a fair number of efficent peptide ligases (about 1 x 1031) could be produced in a under a year, let alone a million years. The synthesis of primitive self-replicators could happen relatively rapidly, even given a probability of 1 chance in 4.29 x 1040 (and remember, our replicator could be synthesized on the very first trial).

Assume that it takes a week to generate a sequence [14,16]. Then the Ghadiri ligase could be generated in one week, and any cytochrome C sequence could be generated in a bit over a million years (along with about half of all possible 101 peptide sequences, a large proportion of which will be functional proteins of some sort).

Although I have used the Ghadiri ligase as an example, as I mentioned above the same calculations can be performed for the SunY self replicator, or the Ekland RNA polymerase. I leave this as an exercise for the reader, but the general conclusion (you can make scads of the things in a short time) is the same for these oligonucleotides.

Search spaces, or how many needles in the haystack?
So I've shown that generating a given small enzyme is not as mind-bogglingly difficult as creationists (and Fred Hoyle) suggest. Another misunderstanding is that most people feel that the number of enzymes/ribozymes, let alone the ribozymal RNA polymerases or any form of self-replicator, represent a very unlikely configuration and that the chance of a single enzyme/ribozyme forming, let alone a number of them, from random addition of amino acids/nucleotides is very small.

However, an analysis by Ekland suggests that in the sequence space of 220 nucleotide long RNA sequences, a staggering 2.5 x 10112 sequences are efficent ligases [12]. Not bad for a compound previously thought to be only structural. Going back to our primitive ocean of 1 x 1024 litres and assuming a nucleotide concentration of 1 x 10-7 M [23], then there are roughly 1 x 1049 potential nucleotide chains, so that a fair number of efficent RNA ligases (about 1 x 1034) could be produced in a year, let alone a million years. The potential number of RNA polymerases is high also; about 1 in every 1020 sequences is an RNA polymerase [12]. Similar considerations apply for ribosomal acyl transferases (about 1 in every 1015 sequences), and ribozymal nucleotide synthesis [1, 6, 13].

Similarly, of the 1 x 10130 possible 100 unit proteins, 3.8 x 1061 represent cytochrome C alone! [29] There's lots of functional enyzmes in the peptide/nucleotide search space, so it would seem likely that a functioning ensemble of enzymes could be brewed up in an early Earth's prebiotic soup.

So, even with more realistic (if somewhat mind beggaring) figures, random assemblage of amino acids into "life-supporting" systems (whether you go for protein enzyme based hypercycles [10], RNA world systems [18], or RNA ribozyme-protein enzyme coevolution [11, 25]) would seem to be entirely feasible, even with pessimistic figures for the original monomer concentrations [23] and synthesis times.

Conclusions
The very premise of creationists' probability calculations is incorrect in the first place as it aims at the wrong theory. Furthermore, this argument is often buttressed with statistical and biological fallacies.

At the moment, since we have no idea how probable life is, it's virtually impossible to assign any meaningful probabilities to any of the steps to life except the first two (monomers to polymers p=1.0, formation of catalytic polymers p=1.0). For the replicating polymers to hypercycle transition, the probability may well be 1.0 if Kauffman is right about catalytic closure and his phase transition models, but this requires real chemistry and more detailed modelling to confirm. For the hypercycle->protobiont transition, the probability here is dependent on theoretical concepts still being developed, and is unknown.

However, in the end life's feasibility depends on chemistry and biochemistry that we are still studying, not coin flipping.

http://www.talkorigins.org/faqs/abioprob/abioprob.html#Intro

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Originally posted by dj2becker
Suppose we put chance to a test which is less simple, yet something that would be quite easy for any school child. Let it spell this phrase: “the theory of evolution.” Drawing from a set of twenty-six small letters and one blank for the space between letters, what is the probability expectance?
All that is needed is simply to get those twenty-three ...[text shortened]... 0,000,000 times the assumed age of the earth!

http://creationsafaris.com/epoi_c02.htm#ec02f06
Adding to all the other arguments against this improbability claim is this:
Life is not trying to spell 'the theory of evolution'. this is just what the end result randomly ended with. For all we know those 23 letters might be put together in a much better way.
For example:
NO TO THY RELIEVE OF THOU
OR HOT YOUTH FELINE VOTE
YOUTH FERTILE VOTE OH NO
HOTFEET LOVER HIT ON YOU

The first one sounds like something your God would say, and the last one looks rather intriguing πŸ™‚

AThousandYoung
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Originally posted by frogstomp
How feasibile is the proposition that Earth's Carbon,Nitrogen and Oxygen were produced in the same supernova and had been forming organic compounds before the Earth formed ? Giving the process a jump start.
No idea. It seems feasible to me.

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Originally posted by AThousandYoung
No idea. It seems feasible to me.
Acetic acid , formic acid,methyl formate , acetic acid,ammonia and glycolaldehyde(real important since its a sugar and a building block of Ribose) among others have been detected in space.
A large number of Hydrocarbon, some with as many as 72 atoms were detected by Cassini in Titan's upper Atmosphere.

This really has increased the size of the original system to include Earth's upper atmosphere. as well as the material that formed the planet ( although high temperatures might be a problem in the latter)

"Glycolaldehyde, an 8-atom molecule composed of carbon, oxygen and hydrogen, can combine with other molecules to form the more-complex sugars Ribose and Glucose. Ribose is a building block of nucleic acids such as RNA and DNA"

http://www.sciencedaily.com/releases/2000/06/000619072351.htm

t
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Originally posted by flyUnity
Im suprised that you and LemonJello refute that DNA dont evolve, Evolutionist claim that DNA came from RNA, I never heard of any scientist say that DNA evolves, as a matter of fact, thats one purpose of DNA, to keep offspring like the parent.

I may be wrong, I just never heard of any scientist say that DNA evolved
Every living thing is evolving. DNA is certainly evolving and changing as well. Of course, it's all so incredibly slow from our everyday perspective that it's really not noticeable in the present moment. This is probably why you don't hear scientists commonly saying that DNA evolves. I think that they all take for granted that every living thing evolves and so they don't point it out too often.

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Originally posted by telerion
Every living thing is evolving. DNA is certainly evolving and changing as well. Of course, it's all so incredibly slow from our everyday perspective that it's really not noticeable in the present moment. This is probably why you don't hear scientists commonly saying that DNA evolves. I think that they all take for granted that every living thing evolves and so they don't point it out too often.
Oh I see, there is no evidence that it evolves, (There's more evidence that it dont) but in order for evolution to be true, it has to evolve.

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Originally posted by flyUnity
Oh I see, there is no evidence that it evolves, (There's more evidence that it dont) but in order for evolution to be true, it has to evolve.
Relax there, hotshot. I wasn't presenting a defense of evolution. I was just telling you that DNA does evolve and giving a reason why you may not have heard a scientist tell you so until here in this thread.

BTW when I say that one doesn't notice DNA evolving in the present moment or from our everyday perspective, I mean it in the same way that one doesn't look at a glacier and remark right away, "Hey, that thing is melting at a rate of 1 inch every 5 years!" Some things take careful research to observe. That's all I was meant by that comment.

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"The course will provide basic principles for understanding factors that govern the evolution of DNA and protein sequences. Students will be provided with the opportunity to learn the formation and evolution of multigene families and other evolutionary phenomena. They also will be introduced to statistical methods and computer programs for analyzing DNA and protein sequence data." (Italics mine)

http://gsbs.gs.uth.tmc.edu/courses/gs110103.html

So, yes there is no evidence for the evolution of DNA and no scientist would say it does evolve and it is not taught at any university.
πŸ˜•

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Originally posted by KneverKnight
"The course will provide basic principles for understanding factors that govern the evolution of DNA and protein sequences. Students will be provided with the opportunity to learn the formation and evolution of multigene families and other evolutionary phenomena. They also will be introduced to statistical methods and computer programs for analy ...[text shortened]... ion of DNA and no scientist would say it does evolve and it is not taught at any university.
πŸ˜•
Thankyou πŸ™‚

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Originally posted by flyUnity
Thankyou πŸ™‚
you're thanking KK for mocking your claims?

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