Debate: Creationism vs. Evolutionism
Side: Evolutionism

Firstly, here are some questions for you creationists: -There is no need of a god, the universe may have simply tarted from a chain reaction of universes collapsing into a space-time singularity and then re-expanding due to entropy. - Assume the previous point is false. Who created god? Can god exist in a dimension where space and time don't exist?- At CERN, physicists were able to create anti-matter using enormous amounts of energy (around 30 Billion kW to create 1 nanogram). How does God get the energy to create the ENTIRE UNIVERSE?- Why does God look human? For all we know there may be so many other living species spread throughout the universe, so why does God, which is their creator as well, look coincidentally like us?-The Earth isn't 6000 years old, there are literally cave paintings that are 5 times older.-Beauty lies in simplicity. Why would God create such complex creatures? For example, why do we have 10 fingers, and not 12 (arithmetics is much easier in base 12).- Fossil records show that evolution is a FACT.Now, here comes the explanation disproving the probability argument that creationists love so much. If you're not a biochemist (why are you even arguing about something you barely know about), then I suggest reading just the part about tossing coins onwards. If you're too lazy to read the explanation, read the final conclusion, since it's pretty important.Having said that, all the calculations saying that the probabiblity of a protein forming is around (1/20)^300 are flawed, they include mistakes: 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.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 and Woese calls a progenote ), 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. The first "living things" could have been a single self replicating molecule, similar to the "self-replicating" peptide from the Ghadiri group, or the self replicating hexanucleotide, or possibly an RNA polymerase that acts on itself . Another view is the first self-replicators were groups of catalysts, either protein enzymes or RNA ribozymes, that regenerated themselves as a catalytic cycle . An example is the SunY three subunit self-replicator . 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.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.CREATIONISTS: simple chemicals ------> bacteriaABIOGENESIS: simple chemicals---->polymers------>replicating polymers----->hypercycle------>protobionts----->bacteria 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.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! 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".﻿ 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. However, inspection of the genome suggests that this could be reduced further to a minimal gene set of 256 proteins . Note again that this is a modern organism. The first protobiont/progenote would have been smaller still, and preceded by even simpler chemical systems.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.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. I could use other examples, such as the hexanucleotide self-replicator, the SunY self-replicator or the RNA polymerase described by the Eckland group, 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 10^40. This is much, much more probable than the 1 in 2.04 x 10^390 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 10^40, a self-replicator could have turned up surprisingly early. But there is more.1 chance in 4.29 x 10^40 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.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.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 10^40, 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 10^24 molecules in it (that's well over a billion billion); a tonne of arginine has 2.85 x 10^27 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 weeksSo 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 10^24 litres. Given an amino acid concentration of 1 x 10^-6 M (a moderately dilute soup, see Chyba and Sagan 1992), then there are roughly 1 x 10^50 potential starting chains, so that a fair number of efficent peptide ligases (about 1 x 10^31) 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 10^40 (and remember, our replicator could be synthesized on the very first trial).Assume that it takes a week to generate a sequence . 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. The general conclusion (you can make scads of the things in a short time) is the same for these oligonucleotides.﻿With that said, it's easy to see how the probability of proteins forming is not (1/20)^300. The reason that we haven't been able to reproduce these findings yet is because it takes time, millions of years maybe...Finally, evolution has been proved. Nowadays, many new technologies rely on evolution, such as in computer science, where evolutionary algorithms are used to simplify complex modelling problems. Now, if evolution were false, these technologies wouldn't work... however they do work, therefore showing that evolution HAS to be true,