Evolution is a basic, biological process

If you figured this out all by yourself, then you're to be commended for your percipacity. I do mean that in all seriousness. That's a remarkably insightful realization.On the other hand if you believe this to be a depature from the "mainstream" evolutionary/biological thinking, then you're misinformed. To my knowledge evolutionists don't propose that environmental pressures stimulate or create certain mutations, but rather, environmental pressures select from pre-existing mutations, exactly as you propose. (Though it is believed that certain kinds of environmental stress in certain organisms can stimulate increased mutation rates in general.)What I guess I mean to say is that you're so right, we've known this for a while. I'm not sure where you got the idea that mainstream biology believed anything else. I commend you for your percipacity, again. Why not? Remember that evolution is mutation and selection; we know that mutation occurs constantly, so any time mutations are being selected for or against by environmental stresses, that's evolution.This message has been edited by crashfrog, 01-11-2005 00:06 AM

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What I meant was that one does not need to understand the origin of the code in order to understand the code itself or how it works.

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So you are saying that "why should we lern about the past and understand the present."?
Well the thing is if we thought like that... religion wouldn't exist. because we have always had the curiosity to find out were things came from
But if you want to copy something, it is much easier to understand how it was created.

The discussion of antibiotic resistant bacteria is very interesting. For more information, you might want to visit these two sites which discuss how antibiotics work and how resistance develops.http://helios.bto.ed.ac.uk/bto/microbes/penicill.htmPage Not Found | FDAHere is an excerpt from the latter site Re these comment from The Lit Sorry if my writings implied a proposal of on-demand evolution. As pointed out in several places, evolution is essentially a random process. With billions of bacteria, dividing relatively quickly (the time interval required for a bacterial cell to divide or for a population of bacterial cells to double is called the generation time. Generation times for bacterial species growing in nature may be as short as 15 minutes or as long as several days.), the simple law of averages predicts that mutations will occur with sufficient frequency to give rise to resistant bacteria in a matter of months if not a couple of years. Whether resistant bacteria are present when the antibiotic is introduced or appear after the antibiotic is introduced is moot. I think someone pointed out that if no antibiotic is introduced, the relative number of resistant bacteria, if any are present, will probably not change very much. But, if an antibiotic is introduced, sooner or later, resistant bacteria will appear and the relative number of resistant bacteria will increase since the non-resistant bacteria will be killed off.The Lit is absolutely correct that antibiotics should be used sparingly — using them to fight viral infections, as is done, only hastens the demise of antibioticsSoplar

OOPs!I'll have to be more careful - very careless of me. Thanks for the correction.Re the interplay between brain scanning an behavioral examination, I'm sorry if I impled that behavioral examination is unimportant or that PET, FMRI, CAT etc obsoleted behavioural examination. I believe that behavioural examination shows what is happening while the scanners are beginning to show the where and why. Both are important, but ultimately we need to know why things happen and external observation is unlikely to provide this information.Soplar

Soplar,Sorry I jumped to the conclusion that you were proposing evolution-on-demand.Consider this snippet from MSNBC: Such claims are common in short news articles about this subject. Per our earlier discussions, we know the defenses already exist and widespread antibiotic use simply makes the bacteria with these pre-existing defenses widespread. IF anything evolved, it did so without the aid of the antibiotic. However, many people (including myself) would read this and think that this article is saying that the antibiotic is causing the evolution.It is only now that I understand that evolutionists may use the term "evolution" to refer to a pre-existing trait being favored as opposed to the development of the trait itself.Consider these selections from your first quoted source, http://www.bioteach.ubc.ca/Biodiversity/AttackOfTheSuperbugs: Once again, it SOUNDS like they are saying that exposure to an antibiotic leads causes the resistant trait to be ACQUIRED. The last sentence really drives home the impression that the term "acquired" is reference to the development of the actual genes.Another of your sources, Page Not Found | FDA, does a better job of making this distinction clear: While I don't believe in evolution, this article presents a more accurate picture of how resistance develops in a bacterial population.But, if the antibiotic is only exterminating the pre-existing, non-resistant variants and favoring the pre-existing, resistant variants, then, when we see resistance develop in a given bacterial population, we are not "seeing evolution occur." Rather, we are seeing a change in the proportion between between two pre-existing variants. This says nothing about HOW the two variants came to be.BTW, did you get a chance to read this post of mine: Message 203?--TheLiteralist

We know that the mutations occurred during the bacterial reproductive process because these experiments have also been performed on bacterial populations raised from a single bacteria. Any genetic differences in the population had to have arisen through mutation, in other words, inaccurate copying of the DNA during reproduction. And the DNA has been sequenced to find the precise mutations that confer the resistance. What part of bacterial evolution don't you accept? That mutations happen? Or that the bacteria best suited for the environment are more likely to reproduce and least likely to die?Just to confuse the issue, let me also comment on this: Experiments indicate that some organisms increase their mutation rate in response to environmental stress. And some mutations are more likely to occur than others simply because of the gene's particular location on a DNA strand. For example, nucleotides that occur at tight bends in the DNA can be more prone to copying mistakes.--Percy

Right. Which is evolution. Both of those things are evolution, because evolution is simply changing allele frequencies. Yes, we literally are. The process you described is called "natural selection", which is one of the two components that change allele frequencies. We know how they came to be, because we know how bacteria reproduce, and so we know where their alleles have to come from. Thse two variants came from random mutation, which is the other half of evolution.Random mutation + natural selection = evolution. When we see a hostile environmental factor selection among alleles, and allele frequency changing as a result, we're literally observing evolution.

Crashfrog, Thanks for the compliment, but, unfortunately, I think I learned this concept in my highschool biology class. I think I have seen many phrases like "the bacteria keep evolving resistance..." in short news articles here and there. Also a chatroom experience makes me think that many folk believe exactly what we have determined is not happening--i.e., that the antibiotic induces the very mutations that cause resistance to the antibiotic. Also, you can look at Message 215 where I show why I thought one of Soplar's quoted articles was implying this. The introduction of the antibiotic merely demonstrates that two general varieties of bacteria exist through selection. Introduction of the antibiotic gives us no clue as to HOW the two general varieties came to be. Evolution is merely an assumption before and after the antibiotic is introduced.There may be SOME example somewhere of mutation and selection working together, but this is selection alone--the mutation event is not proved in this case.I would think it would be very difficult to prove that any beneficial trait is the result of a mutation unless the genetic code of the particular organism were completely understood before and after the arrival of the new trait. Otherwise, how would one know whether the new trait wasn't merely a function of the existing code that had only recently been implemented (i.e., sort of like a giant database, not all of which is being used at any given time) or even there might be a sort of random generator in the code that allows variety¹ within limits for certain traits. I seem to recall that the human immune system employs some sort of random generator.What is percipacity? It's not in my online dictionary or my desk dictionary. It sounded like a good compliment...even though I didn't actually deserve it.

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¹Corrected spelling via edit.This message has been edited by TheLiteralist, 01-11-2005 20:24 AM

And, although the change that confers resistance in any particular experiment often differs (that's the way evolution works), in many cases we can identify the change and show that it was not present in the original bacterium is present in the final population. For example, in many experiments resistance to streptomycin is conferred by a single point mutation in the rpsL gene, coding for a particular ribosomal protein (S12). "AAA" in codon 42 mutates to either "ACA" or "AGA" and the bacterium laughs at streptomycin. See, for example, Novel ribosomal mutations affecting translational accuracy, antibiotic resistance and virulence of Salmonella typhimurium.

Sorry, wrong. The mutation event is proven. In many of the experiments, literally thousands of them, the fact that a random mutation conferred the antibiotic resistance is a result of measurements, not assumptions. A little simplistically put you start with one bacterium, sequence its genome, grow a culture from it, introduce the antibiotic, grow the survivors, re-introduce the antibiotic, and repeat until you have a mostly resistant population. Then sequence the genome of a few of the resistant populaation, compare it to the original, note the differences, then run other tests to determine what the differences do.See, for example, the link I posted in my message just above this one. {edited to add: see also Acquisition of Certain Streptomycin-Resistant (str) Mutations Enhances Antibiotic Production in Bacteria.}Evolution is not assumed, it is measured.This message has been edited by JonF, 01-11-2005 20:45 AM

Hi JonF,What words do those abbreviations stand for?Thanks.

Hi TheLiteralistFor someone who doesn’t believe, you know a lot about it.Yes I did read your 203 response, just haven’t had time to prep a reply. So I will combine the two.Re your two comments in 203 I think this is somewhat along the line I was taking. One can go to school and learn about quantum mechanics without going through all the steps that led to QM. But, as someone who has gone through the steps, I find my understanding is better for it.The same is true of genetics, I suppose one can learn about the genetic code and its relationship to DNA plus how mutations occur due to DNA copying errors without encountering evolution. BUT, when one starts to use genetics experiments with the fruit fly to learn about human DNA, perhaps one might want to know why the DNA of the fly and human are close enough to do this. Also, as a person studies the genetic structure of various animals, one finds that the DNA is very simple in the lower forms, becoming increasingly complex as one approaches the human, one might want to know why. Also, the genetics student will learn that the DNA of chimpanzees differs from humans by only a few percent.So, while one can learn genetics without touching evolution, it’s much easier if genetics is taught using evolution as a backdrop. For example, I suppose you could just say these fruit fly genes are identical to these human genes so we going to experiment with the fly. I would be amazed if someone didn’t ask why this is so.Regarding I suppose that in the strictest sense, this is probably true, but modern biology is just not done this way. The latest copy of Science arrived yesterday and many of the articles made either direct or indirect references to evolution. Most scientists assume a knowledge of evolution.Regarding you comment in 215 Not sure what the this is. If it is the article, the article doesn’t explain How since it doesn’t have to. The author probably assumes everyone is familiar with evolutionFinally, a qualification re modern biology is unintelligible without evolution It doesn’t mean one can’t understand modern biology without evolution, but as I indicate above, one can’t make much sense of such things as the literature of modern biology without evolutionSoplar

I have to disagree with the weakness of this statment.Without evolutionary theory there is simple no way to explain the nature of life on the planet. The nature of all living things, their relationships to each other and how they could have gotten that way can't be explained. The pattern of life past can't be explained.None of what we see as the big overall picture makes any sense any other way.Then the details and odd nature of living organisms is just a mystery without the explanation supplied by evolutionary theory.In each case you might say that God choose to make it that way and think it is an explanation. The very next question would be why in the world would he pick such a cockamaymie way of doing it?

Soplar,Thanks for the post.This first: Okay...if I stayed completely ignorant of the evolution theory I would have trouble understanding most journals (actually understanding more about it than many who believe it, I still find biology journals unintelligible, but that has more to do with me having a highschool biology knowledge and trying to read PhD materials.)I could go with this qualified statement. But, I think you see by now (and remember I have only a highschool biology background), a YECer can learn a lot about evolution, too. Thus your statement, which makes me grin a bit: Well, thank you. I don't know enough, I assure you...not enough to grapple with biologists or, even worse, geologists (and I certainly don't dislike the geologists here, but they have quickly demonstrated that I shouldn't say much about geology right now...a lesson I have forgotten and learned again). My knowledge of geology is woefully pitiful./reminiscing begins/
Not only that...I HATED Biology in high school. Too many little nit-picky fact to remember. I hated chemistry for the same reason. Now PHYSICS...I enjoyed that quite a bit...I took a college level physics course in high school and calculus, too. I liked math and physics...forgotten most of it by now, though...especially the calculus...it's all gone...all I remember are the words "limits" and "functions" and "derivatives."From physics I remember "vectors"...that was key to so much...but all is lost. I retain only the general idea of net forces and acceleration.Anyways...
/reminiscing ends/ In case you have not previously encountered the idea of a common Designer, I shall summarize the idea here (and not too well, I'm afraid). The basic idea is that the world's organisms have many traits in common (esp. the basic DNA code) because they were all designed by the same designer. On the other hand, since the Designer was creative as well as intelligent, He designed diversity into the lifeforms as well. So, yes, even in the Creationists' framework, we could conclude that we could learn something about humans by studying fruitflies...in particular the DNA...as that is the code used by most all organisms.Regarding chimpanzees and humans, there are many obvious similarities and differences...and we are made by the same Creator (in my view)...so I am not surprised that there are many similarities in the codes for both creatures as well as differences. Also, what does a 2% difference work out to be as far as the actual number of base pairs is concerned? And most importantly, what does that different 2% code for?Have you enjoyed the debate so far? They close the threads down around 300 posts...there's not much left to this one. I think we've done a fair job so far covering all your several points. If there's any point from your opening statements that you wished to cover...now's the time to bring it up...or you can resubmit just that one point for approval as a new topic. One-point topics are the easiest to discuss, in my opinion, and tend to get approved more easily, I think.I've learned and am learning much about the art of debate here at EvC. There are fantastic lessons to be learned in that area in this forum.Regards,
--TheLiteralist

AFAIK they aren't abreviations, although they may be. I think they're just names.