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Friday, August 26, 2011

Does Evolution explain how life was created?

Evolution does not care about how the universe started or how life was formed on Earth. When people make this claim, they are creating a straw man argument. The Theory of Evolution discusses how existing life changes over time. That life could have been created by the biblical god, the Greek gods or Quetzalcoatl, The Aztec Plumed Serpent god. It makes no difference to the theory whatsoever. The theory of evolution applies as long as life exists. How that life came to exist is not relevant to evolution. Claiming that evolution does not apply without a theory of abiogenesis makes as much sense as saying that umbrellas do not work without a theory of meteorology.

They are actually arguing over Abiogenesis, which is the theory of how life was started and the Big Bang Theory, which is the current idea of how the universe was created. However, even if those ideas are completely wrong, that would not change one thing about the Theory of Evolution. They are not interdependent and do not require each other to be accurate. However, Abiogenesis is a fact. Regardless of how you imagine it happened (note that creation is a theory of abiogenesis), it is a fact that there once was no life on earth and that now there is. Thus, even if evolution needs abiogenesis, it has it.

This is an article of one creationist site trying to discount evolution. I am showing it since it is common of the arguments against evolution. 

Schroeder cites a Wistar institute conference as showing evidence of the improbability of evolution. The symposium was transcribed from audio and published in 1967 as Mathematical Challenges to the Neo-Darwinian Interpretation of Evolution, a Symposium Held at the Wistar Institute of Anatomy and Biology April 25 and 26, 1966, Paul Moorhead and Martin Kaplan, eds. Needless to say, this is quite out of date. Worse, it does not support Schroeder at all. Only one paper comes anywhere near proposing that the origin of life and subsequent evolution is improbable: Murray Eden, "Inadequacies of Neo-Darwinian Evolution as a Scientific Theory" (pp. 5-20). He does not really argue that evolution is improbable, but rather that no present theory accounts for certain peculiarities of life on earth, especially the fact that all living organisms are composed of a very tiny fraction of all the possible proteins.
In particular, Eden argues that given all "polypeptide chains of length 250 [amino acids] or less...There are about 20^250 such words or about 10^325" (p. 7). This number is ripe for quoting, but it does not stand as the odds against life, and even Eden did not even imply such a meaning--to the contrary, he admits that perhaps "functionally useful proteins are very common in this space [of 10^325 arrangements]," and facing tough criticism in a discussion period (where his paper was torn apart, pp. 12-9) he was forced to admit again that perhaps "there are other domains in this tremendous space which are equally likely to be carriers of life" (p. 15). But his main argument is that life is concentrated around a tiny fraction of this possible protein development "space" and we have yet to explain why--although his critics point out why in discussion: once one system involving a score of proteins was selected, none others could compete even if they were to arise, thus explaining why all life has been built on one tiny set of proteins. One thing that even his critics in discussion missed is the fact that his number is wrong: he only calculates the number of those chains that are 250 acids long, but he refers to all those and all smaller chains, and to include all of those he must sum the total combinations for every chain from length 1 to 250. Of course, the number "250" is entirely arbitrary to begin with. He could have picked 100, 400, or 20. He gives no arguments for his choice, and as we have seen, this can have nothing to do with the first life, whose chain-length cannot be known or even guessed at [5].
Among the huge flaws in Eden's paper, pointed out by his critics, is that he somehow calculates, without explanation, that 120 point mutations would require 2,700,000 generations (among other things, he assumes a ridiculously low mutation rate of 1 in 1 million offspring). But in reality, even if only 1 mutation dominates a population every 20 generations, it will only take 2400 generations to complete a 120-point change--and that even assumes only 1 point mutation per generation, yet chromosome mixing and gene-pool variation will naturally produce many at a time, and mix and match as mating proceeds. Moreover, a beneficial gene can dominate a population faster than 20 generations, and will also be subject to further genetic improvements even before it has reached dominance. I discuss all of these problems in my analysis of Schroeder above. But in the same Wistar symposium publication, C. H. Waddington (in his "Summary Discussion") hits the nail so square on the head that I will quote his remarks at great length:
The point was made that to account for some evolutionary changes in hemoglobin, one requires about 120 amino acid individual events, as though it is necessary to get one of them done and spread throughout the whole population before you could start processing the next one...[and] if you add up the time for all those sequential steps, it amounts to quite a long time. But the point the biologists want to make is that that isn't really what is going on at all. We don't need 120 changes one after the other. We know perfectly well of 12 changes which exist in the human population at the present time. There are probably many more which we haven't detected, because they have such slight physiological effects...[so] there [may be] 20 different amino acid sequences in human hemoglobins in the world population at present, all being processed simultaneously...Calculations about the length of time of evolutionary steps have to take into account the fact that we are dealing with gene pools, with a great deal of genetic variability, present simultaneously. To deal with them as sequential steps is going to give you estimates that are wildly out." (pp. 95-6)

There is a great deal about abiogenesis that is unknown, but investigating the unknown is what science is for. Speculation is part of the process. As long as the speculations can be tested, they are scientific. Much scientific work has been done in testing different hypotheses relating to abiogenesis.

There is still the same, single, fundamental problem with all these statistical calculations, one that I mention in my review of Foster: no one knows what the first life was. People like Morowitz can try to calculate what is, at a minimum, possible, and laboratory experiments, like that which discovered the powers of tetrahymena (see Addenda C), can approach a guess, but these guesses still do not count as knowledge, and it is not sound to claim that simply because we don't know what it was, therefore we can't assume there was such a simple life form. And even if we accept such an argument, to go from there to "god" is essentially a god-of-the-gaps argument. When we did not know how the bumble-bee flew, was that an adequate ground for positing god as the answer, or was it instead cause for further scientific investigation aimed at finding out the natural explanation? All of science is the result of choosing the latter approach. Once there was a time when nothing was explained. Since then, everything which has been explained has been found to have a natural, not a divine, explanation. Although this does not prove that all future explanations will be of like kind, it shows that it is not at all unreasonable to expect this--and it is not a very reliable bet to expect the opposite.

Theories which make the origin of life plausible are hypotheses like any others, awaiting future research--in fact, generating that research. On the other hand, in the words of Frank Salisbury, "Special creation or a directed evolution would solve the problem of the complexity of the gene, but such an idea has little scientific value in the sense of suggesting experiments." And the experiments suggested by Salisbury and his colleagues led, in fact, to a simplification of the very problem that vexed Salisbury in 1969. Science, once again, gets somewhere. Creationism gets us nowhere. Coppedge suspected in his day "many evolutionists have avoided such investigations [into the odds against life forming] because they intuitively recognize that it will threaten evolutionary doctrine" (p. 234). Yet scientists hardly avoided the matter at all. Quite to the contrary, while creationists engaged in no actual research for twenty-five years and contributed nothing to our understanding of biology, scientists chewed away at the very problems Salisbury and Coppedge discussed, and solved a great many of them (see Stuart Kauffman, The Origins of Order: Self-Organization and Selection in Evolution, 1993). That none of them thought to make arbitrary and groundless guesses for the purpose of calculating a useless statistic is a testament to their wisdom, just as it is a testament to the ignorance of those, like Coppedge, who actually do this. We only need consider which has added to our knowledge to see who is making better use of their time.

If someone wants to argue against an idea, they should learn what the idea is in the first place.

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