Friday, September 02, 2005

Response to Difficulty of Random Formation of Life

Those in the evolution debates frequently hear, "Life's formation according to the DNA/RNA/etc. model is so amazingly complex that it could not have happened by random chance." It's a daunting argument, because it seems to have good science behind it. But a little good reasoning and it falls like all other empty ascientific arguments. An example is available here: Here is my rebuttal.


First of all, as points out in a similar vein, your argument at best questions the beginning of life. But you have offered zero rebuttal to Darwinist methods once life has been created. Notice that Darwin had nothing to say about cosmology, primordial soups, etc. The problem is that arguments like yours that blanket “evolution” to include very disparate things means that one in essence throws the baby out with the bathwater (assuming the bathwater is tainted in the first place.)

Second, mathematicians may call 10 to the 50th “impossible”, but in fact such numbers matter in cosmological terms. All of string theory depends on 10 to the 100th or larger random quantum deviations in an empty universe creating Big Bang-like events; in fact, it requires not just this, but also selecting our universe out of numerous possible string sets, an even more infinitesimal possibility. Yet I have not heard people rebutting science's declaration in this area with religious motivation; indeed, to do so (though some, like Pat Robertson, seem to object to the Big Bang, as the above article notes) would be silly, since the Big Bang proves that the universe had a discrete beginning, a vital argument for a Christian to win. Give the billions of years in which life has had to evolve, plus consider that there are trillions of planets to choose from (your argument assumes Earth as historically unique, a fantastically large fallacy), and life can emerge even given your sanguine calculations. Notice how, in one case, science says that the chances are not so daunting and Christianity seeks a way to disprove that; in another case, science says that the chances are daunting and Christianity accepts that. The problem with those seeking for God's footprints is that they will find them, no matter where they look.

But in fact numerous explanations including protein-like structures from meteors, primordial soups or sandwiches, have been proposed. Take this:

“What about the argument concerning the statistical improbability of obtaining a specific 141 amino acid sequence by looking for the correct sequence among randomly generated sequences? Certainly this mechanism could not explain the origin of protein sequences, but the creationist suggestion that this mechanism is part of evolutionary theory is false; it is a "straw-man" -- a false creationist caricature of evolution -- used repeatedly by creationists to mislead naive audiences into thinking that evolution is illogical. It is false because it demands a specific sequence in a SINGLE selection step from a pool of random sequences, whereas the real evolutionary model for the origin of protein sequences involves MULTIPLE ROUNDS OF RANDOM MUTATION followed by MULTIPLE selection steps as outlined above.

In a beautiful discussion of the distinction between these two models, British biologist Richard Dawkins (The Blind Watchmaker New York, 1986) simulated the creationists' straw-man caricature on a computer. He programmed the computer to generate random sequences to see if it would ever generate a line from Hamlet: "Methinks it is a weasel." This line has 28 characters (including spaces), so the computer was programmed to make 28 selections from the 27 possible characters (26 letters plus space). A typical output was


Since there are 2728 different possible ways of choosing from 27 alternatives 28 times, one can calculate the probability of picking the correct sequence and, based on the speed of the computer, estimate how long on average one would have to wait for the correct sequence to be printed. Dawkins figured a million million million million million years. If this were the best way protein evolution could be conceptualized -- by selection in a SINGLE step from random sequences -- one might conclude, along with the creationists, that a protein sequence could not have evolved. But the creationists' single step selection model is clearly a "straw-man" designed to ridicule the concept of randomness as a component of evolution. The real evolutionist model is that modern amino acid sequences evolved by successive steps in which random mutations of pre-existing sequences were subjected to selection; any rare mutant that provided more efficient function was propagated to future generations, in which the process of mutation and selection was repeated over and over. When Dawkins terminated his computer program simulating the straw-man "creationist version" of evolution and rewrote a program that more closely approximates the "evolutionist version" of evolution, the results of the simulation were quite different. Dawkins programmed the computer to generate an initial sequence randomly, as in the first model, and the computer produced:


Then, following Dawkins's revised program, the computer made multiple copies (progeny) of this sequence, while introducing random "errors" (mutations) into the copies. The computer examined all the mutated progeny and selected the one that had most similarity (however slight) to the line from Hamlet. This selected sequence was used as the basis for another generation of progeny with further mutations, from which the best copy was again selected -- and so on. By ten generations, the sequence had "evolved" to


By thirty generations, it was:


Instead of taking millions of years, the computer generated METHINKS IT IS LIKE A WEASEL in about half an hour, at the forty-third generation. Thus a cumulative multi-step model is not at all implausible as a model for evolution, given both a mechanism for replicating imperfect copies and a strong selective pressure. (The replication mechanism is, of course, a big "given"; how such a mechanism might have developed is a separate question concerning the origin of life rather than its evolution, and is not the subject of this article.) The importance of Dawkins's simulation is that it highlights the error of all the creationist arguments against the statistical improbability of evolution, by showing that the creationists' choice of a single-step versus cumulative multi-step model creates a falsely low estimate of the potential for deriving a particular sequence via random mutation and selection. Although both the single-step model and the cumulative multi-step model involve random sequences and selection, the predicted consequences of the two models are very different. The creationists ignore this difference and intentionally discuss only the model that gives the result they like, even though this model corresponds least well to the theory of evolution.”

What is amazing about evolution from a scientific standpoint is precisely its aesthetic: how supple it is, how well it has been documented on micro-scales (the butterflies in England turning to black wings, fruit fly studies, the fact that bacteria evolve, etc.) The resistance to evolution is not just about abstract models. Evolution (say, in the above case of bacteria gaining resistance) is a vital thing to understand.

What scientific experience do you have? You've clearly done some research, but have your
findings been analyzed in a peer reviewed journal? Far be it from me, an anarchist, to fetishize expertise, but there is something to be said for the stringent process of peer review and debate that goes on in science: Easy to catch fallacies, like the numerous ones you've exercised, can be spotted.

Now, admittedly, there is a serious question about how one gets from amino acids to the entire complex DNA/RNA/ribosomes/proteins. The question for the scientifically minded is not, “Where can we squeeze God in?”, but rather, “Is there an intrinsic aspect to such chemical formations that they are in fact very easy to form, such that life is everywhere? Or are they indeed nearly impossible, such that they will only appear on a few lucky planets?”

And the nail in the coffin argument: You imply that opposing your arguments would be Christophobia. But that's ridiculous. Even if you have shown a gap in the existing structure of knowledge, this does not prove that said gap must be filled by God: the “god of the gaps” fallacy. It simply means the state of the art has not advanced to explain it. Of course, to say that science must come up with an answer is also a claim of faith, and people should stop saying it. People should also stop saying that they think there's a rational explanation. “God did it” is rational if it is true or verifiable. Nonetheless, armed with your logic, one could easily have said that we should not teach Newton; for who knows what the aether is? We should not teach quantum theory because many things remain unexplained. To abandon theories, however incomplete, with useful predictive value for a religiously-based hypothesis (that, by the way, advances the Judeo-Christian God not at all; couldn't Zeus or Brahma be controlling this?) is sheer lunacy, especially if the proposed alternative is the pointedly uninsightful and useless “God chose it to happen that way”.


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