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  Topic: A natural process for creating information, A reply to a claim by Phillip Johnson< Next Oldest | Next Newest >  

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Joined: Jan. 2006

(Permalink) Posted: Jan. 26 2006,21:23   

In the ID-Files section of this BBS, under the topic "Phil Johnson, Links to interviews, works, reviews, etc", niiicholas quotes Phillip Johnson as saying, "The scientific key is, "No natural processes create genetic information." As soon as we get that out, thereís only one way the debate can go because Darwinists arenít going to come up with a mechanism."

Professor Johnson should read a little on the subject before opening his mouth.  Darwinian evolution has a mechanism for creating genetic information that's simple enough for even a lawyer to understand if he tries hard enough.

I was going to write this to Zardoz in the "After the bar closes/Official Uncommon Pissant Discussion Thread", but he has shown himself to be emotionally resistant to all attempts at education, so I'll post it here where it can be read by people who are emotionally capable of understanding the concept.  Professor Johnson is invited to read and comment if he's in that group.

Abstract: Mutations create new genetic information.  Natural selection tests the new information to see if it's useful or not where "useful" is defined as improving the ability of the organism to produce more offspring capable of reproducing the new information.  If the new information is useful, natural selection leaves it in the genome, if it's not, it gets rid of it.

Detail: Suppose you have a stretch of DNA that contains this sequence: "CAGTAGTTAC".  If the organism that contains that stretch of DNA reproduces and the DNA is copied perfectly, the offspring will have the exact same sequence of DNA and there will be no new information generated.  (In one of his books, Dembski compares this to printing a second copy of a book.  No new information is generated, the information that already exists is merely copied.)

Now suppose that an organism with that stretch of DNA reproduces and an error is made copying the DNA.  Suppose that "CAGTAGTTAC" becomes "CATTAGTTAC".  This is new information because it's not exactly the same as the original sequence.  

So we have new information, courtesy of mutation/copying errors, but we don't know if this new information is bad, neutral or one of the rare instances of good new information that improves on the original.  The odds are low that the new information is an improvement.  As Richard Dawkins once said, "...however many ways there may be of being alive, it is certain that there are vastly more ways of being dead!"  Similarly, there are 4^10 or 1,048,576 different ways of arranging 10 DNA base-pairs and most of them won't do anything useful, which is lethal if the organism is depending on those ten base-pairs to do something vital.

So how do we find out if the new information is useful or harmful?  Simple, we allow the new organism to try to make a living and reproduce using the new DNA sequence.  Most of the time, the new organism does as well as its parent did because most changes in the DNA sequence change non-functioning "junk DNA" or code for amino acids that are buried deep inside a protein molecule and have no effect on how it works.  If this turns out to be the case with the new DNA sequence, then mutation has given us two different ways of making DNA that can successfully run this specific organism - the original DNA and the new mutated DNA.  This is creating new genetic information through a natural process, Dr. Johnson!  

Before the mutation, we had one set of information that would run a successful organism, "CAGTAGTTAC".  After the mutation, we have a second set of information that will run a successful organism, "CATTAGTTAC".  This is not the same as printing another copy of an existing book, it's printing a second book that differs from the first, but which works just as well.  It's new genetic information!  Since the new information is no better than the original, organisms containing the new DNA may increase in numbers or decrease or disappear altogether.  This is the "genetic drift" you hear about.  An organism has new DNA, but it works as well as the old DNA, so nothing much happens.

If the new DNA sequence does make a difference in how the organism functions, the odds are that it will make the organism work worse than it's parent.  Remember that there are lots more ways of being dead than alive.  In the extreme case, the organism won't function at all and it will die.  If it dies before it has a chance to reproduce and copy the new DNA, the new DNA sequence dies with it and all the other organisms carry on with the original DNA.  Mutation generated some new information and natural selection tested it, discovered that it was bad and got rid of it.  We're back to where we started.

If the organism lives, but doesn't function as well as its parent(s), it may reproduce, but it won't reproduce as successfully as organisms with the old, original DNA and over the long run the organisms with the new DNA will be crowded out and disappear, taking their new but less effective DNA with them.  Again, the other organisms, with the original DNA, will continue to live, preserving the old DNA sequence.

In the rare case where the new DNA works better than the original sequence, the organism will tend to reproduce better than it's parents and it will gradually spread and increase its percentage of the population until it eventually takes over and replaces the old DNA sequence with the new, improved sequence.  

That is how new, useful information is created by the natural process of evolution:  Mutations create the new information, natural selection (which means, basically, having the new organism try to make a living with the new DNA) tests it, destroys new sequences that don't work as well as the original and preserves new sequences that work as well as or better than the original.

Your turn, Dr. Johnson.

  0 replies since Jan. 26 2006,21:23 < Next Oldest | Next Newest >  


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