Russell Husted, a fellow blogger not to be confused with Rusty, left a couple of comments in response to postings far down on my page, so I thought I'd move them up toward the top and answer them before they scroll off entirely. I hadn't noticed them until now. One was in response to my post concerning the Richard Dawkins incident. Russell wrote:
You said of the question:"Can you give an example of a genetic mutation or an evolutionary process which can be seen to increase the information in the genome?", that it is absurd. Why?You also say Dawkins eventually gave a good answer. Can you repeat, or link me to it?
Certainly. Here is Dawkins' response to the question (not his bungled response during the interview, but his actual response published later). And here is mine...
The reason the question is absurd, in my view, is that it presumes, or at least implies, a serious misunderstanding of what evolution requires. It seems to presume that there is a simple way to measure the amount of information in the genome and that evolution requires with each successive change a mere increase in the total amount of information. The person asking the question must have the notion that evolution progresses by successive and discrete additions of information with each new...what? Each new mutation? Each new mutation that is preserved? Each new trait developed within a species? Each new species that splits off? This goes unspoken. In and of itself, the question makes little sense. How would one measure a raw increase of information? An increase in the number of chromosomes? An increase in the number of genes or base pairs per chromosome? This also goes unspoken. If all they are asking for is a mere increase in the total amount of genetic information in the genome, then we know of several mechanisms by which it can not only increase, but double with a single mutation. That's what polyploidy does, and we observe polyploidy all the time, especially in plants. Gene duplication would also increase the total amount of information in the genome. As Dawkins points out in his response, the crested newt has a genome several times larger than the human genome, which is the result of gene duplication. And that fact, at the least, means that the unspoken assumption of the question above - that there is a correlation between the amount of information in the genome, as opposed to how the information is expressed in the phenotype is the key to evolution - is false.
It should also be said that an increase in the amount of information in the genome is not required for a new trait to emerge, and this has also been observed. For example, the nylon-eating bacteria. A single frame shift mutation allows for an entirely new trait - the ability to metabolize nylon. We know that this is a new trait for the obvious reason that nylon didn't exist a few decades ago. This frame shift mutation neither increases or decreases the amount of information, it simply shifts the sequence by a nucleotide or two. Yet an entirely new trait evolves and is preserved, and the amount of information has nothing to do with it. That's why I say it's an absurd question, because it betrays, at the very least, a serious oversimplification of evolutionary genetics.
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Ed, I think we have a problem in communication, here. Evolution is a word of many meanings, a theory of many parts and variations, and truly a buzzword that buzzes very differently depending where it is flying. Im not even sure youre being all that consistent in how you use it, or what you mean.
Among other things, you ought not treat adaptation, phenotypic change, change in gene frequencies, genetic drift, even mutation, etc., as evolution. These are merely biological changes through time, to quote Kathy Cox. They may be looked at as possible evidences for evolution, considered possible mechanisms that could lead to evolution, or facts to be explained by a theory of evolution, but they are not evolution. Even adaptation that ultimately accomplishes speciation is not proof of the common meaning attached to evolution.
An example of your own confusion is your example of the nylon-eating bacteria. Though you might assume it, you cant really prove that that is an example of evolution. You err in your assumption that because nylon didnt exist 30 years ago, the ability to eat it is new. Sorry, but a lot of adaptation involves utilizing pre-existing abilities in new ways. The ability to metabolize nylon may have been there all along, but is only now being exploited. Suppose we can show that a new genetic mutation actually occurred (and wasnt already existing in a small frequency among the population) to create that new trait. Is that evolution? Depends very much on your definition. It still fits Kathy Coxs phrase. It also fits descent with modification. And if these bugs will even lose their ability to eat other things that they once ate, some may call it speciation. But is it? More importantly, is that evolution? You tell me, because Im not certain of your definition.
It seems to me that you usually use evolution in the way the lay public seems to, considering it a process by which new, and novel, and ever-increasingly complex forms of life come about. But thats a tough thing to prove. Your nylon-eating bug is not relevant to that theory - by using it you either are confused yourself, or trying to confuse your readers. And using it, you seem to be trying to duck the sensibility of the question about increase in information. I dont think its absurd if the theory and process being advocated is that evolutionary events (as opposed to mere adaptation, even speciation events) are responsible for evolving higher and more complex forms of life. If that is what is under discussion, then it is not absurd because the genome of higher, more complex forms is almost, if not demonstrably always, one of greater information content.
It is silly to say we cant measure the information content. We do try, and we are getting better at it. Weve tried using volume of DNA and chromosomal counts; weve tried gene counts, and protein counts; and today we are developing even better measures. There is some correlation between the amount of information in a genome and the complexity of the phenotype expressed, both in body and behavior. The correlation is not 100%, any more than the correlation between the size of a software program and what it can show on the monitor and perform in the computer.
I think you are ducking behind a smokescreen, pretending not to know where that question was going, or why. The first and biggest quantum leap in information content in a living organism, of course, had to be the leap from atoms and chemicals strewn about a beach or pond, to a genome assembled and working and reproducing in a cell or protective enclosure. Evolution theory goes outside itself to try to explain/account for that, and opponents rightly challenge you on that.
The next step is the meat and potatoes of evolutionary theory (and philosophy) itself. The general paradigm is this: We have a living cell with a genome; a mutation occurs (almost always fatal, but) which is (necessarily, once in a while) actually constructive (adding new information, or constructively changing the read), making possible a novel and useful structure and behavior; it results in a new species; this is repeated a zillion times, resulting in many new species, AND some increase in information, some added information, in one or more species, that manifests in more complex behavior (far more important than structure in this paradigm) and possibly, occasionally, some more complex structure.
Most mutations amount to loss of information. At least they lose relevant information. And natural selection says irrelevant information in a genome is a loser. But a rare few mutations can add information. Sure, some, like the nylon-eating gene, might only change and not add to the amount, but this is not what evolution is all about. Without progress, without adding information, we only have a never-ending proliferation of species of single-cell creatures. Not what Evolutionists believe in, want to believe in, and expect to replace divine or intelligent design theories with.
So I asked my question. I dont like your answer. I dont think the question betrays a serious oversimplification of evolutionary genetics. I think your response betrays a serious oversimplification of evolutionary theory, and the questioners intelligence. Evolutionists (the true believers who elevate a reasonable scientific paradigm into a theology) never like anyone trying to apply thermodynamics (entropy) and information theory, but I think they are appropriate, particularly when questioning the big bang episode (first life) and the trend toward higher and more complex forms.
I think the only problem in communicating that we are having at the moment is that you seem to want to change the subject to something entirely different. The issue at hand in this particular thread is whether the question "Can you give an example of a genetic mutation or an evolutionary process which can be seen to increase the information in the genome?" is a reasonable one or not. The first three paragraphs of your response were irrelevant to that issue. We can discuss definitions of evolution and all the different ways the term can be used, but it's not really relevant to this question. Now on to the parts that were relevant.
"It is silly to say we cant measure the information content. We do try, and we are getting better at it. Weve tried using volume of DNA and chromosomal counts; weve tried gene counts, and protein counts; and today we are developing even better measures."
I didn't say there's no way to measure the amount of information in the genome, I said, "It seems to presume that there is a simple way to measure the amount of information in the genome and that evolution requires with each successive change a mere increase in the total amount of information." Your response only proves my point - you named 3 different ways of measuring information in the genome, and that's not even mentioning the multiple definitions of information that there are. The question, as asked, doesn't specify how information is measured, nor what is even meant by information. If you use any of the three definitions you posted, then of course we know of genetic mutations that increase the amount of information in the genome. I named two of the ways it happens, gene duplication and polyploidy, and those are both regularly observed both in the lab and in the wild. These can increase the total amount of DNA in an organism, the number of genes per chromosome, the number of chromosomes, and the number of proteins produced. There, the question is answered, right?
I don't really mean to appear so flippant about this, but the issue at hand was whether the question, as asked, was absurd or not. There may be related questions that could be asked that are more reasonable and don't show such an oversimplification of genetics, but that's not really relevant to what I said or the issue you raised about it. Having said that, the related questions that you bring up in your second response do deserve a much more thorough answer, but that will have to wait for now. I will post a more detailed answer to the main page soon, but it's behind several others that I plan to do. Stay tuned.
I do like this answer. And looking back over the first, I think I owe you an appology. Looking again, carefully, I think you did give a good answer the first go-round, and I missed it - I need to slow down, I guess. I walked in (figuratively) with expectations and a mindset that didn't do you justice, and I just hope there's a new more tasty crow in the works.
I do think you were off in your nylon-eater, but even there I was too personally critical.
Actually, I quit debating evolution some years ago, because both sides tended to be abusive, and rarely knew what they were talking about. I came across your exchanges with Rusty, and thought you were a cut above the usual "Evolutionist". I think, in this instance, I saw more what I expected in the old days, and deserve my dish of crow.
I haven't mastered the art and technology of this blog stuff, and can't keep track of the sites I like, or exchanges (ie, didn't know if/when you responded to my comment). I think the system (like trackback) does do that, but I haven't figured it out yet. I'll try to keep you on my "to do" list, and check for future responses.