Friday, March 09, 2007

Is Drug-Resistant Bacteria An Argument for Darwinian Evolution?

The past couple of days, I have been a bit under the weather. I finally went to the doctor today who, after poking and prodding, diagnosed me with a very scientific-sounding ailment. He said: “You’ve got The Crud.”

Apparently, The Crud is currently going around; many people have had it. Basically, it’s just a glorified head-cold. So the good doctor slapped out a prescription for some antibiotics and sent me on my way to heal.

This got me to thinking about drug resistances in bacteria. Quite often, the occurrence of drug-resistant strains of bacteria is used as a “proof” for Darwinian evolution. Basically, the claim goes like this:

When a drug is introduced into the environment bacteria live in, a certain number of bacteria will be drug-resistant. Those bacteria that are not drug-resistant die off, leaving behind only the drug-resistant strain of bacteria. Since only the drug-resistant strain can propagate (as the non-resistant strains are dead), in short order you have a “new species” of bacteria that is resistant to the drug, and the drugs no longer work.

There is nothing wrong with the above illustration until you get to the term “new species.” In reality, no new species were created. We started with two types of the same species of bacteria—one resistant, the other not—and one type was killed off. This is identical, by the way, to what happened with the famous “peppered moths” illustration, where the light moths died off when pollution turned the trunks of the trees dark.

And, in reality, it is no different than any adaptation. For instance, a wolf in the northern steppes of Russia may have longer hair than his brothers in more temperate climate. If we rounded up some random wolves, killed off certain wolves without a specific length of fur, we’d have the same result as with the peppered moths and the drug-resistant bacteria. It is, indeed, something that breeders have been doing for centuries—that is, artificial selection for certain traits within a species.

However, just as wolves with varying lengths of fur and moths with different colored bodies are still members of the same species, so too are drug-resistant bacteria strains in the same species as non-resistant bacteria. In other words, if you have E. Coli in a Petri dish, some of which is resistant and others not, every bacteria cell remains E. Coli. The drug-resistant E. Coli is not a different species.

Perhaps this can best be illustrated by moving the argument to the human level. Human beings naturally range in tolerability toward some diseases. Some people are immune to the effects of a particularly ravishing disease. Others are not. However, in no case would we consider an immune individual to be a different species than a non-immune individual. People from each group are still human beings, capable of reproducing with each other, etc.

So, far from being an argument for species evolution, at most drug-resistant bacteria merely demonstrates the adaptability of an organism. The problem for the Darwinist is that adaptability is not a sufficient step toward species evolution to make species evolution viable.

The variations possible in any organism are limited. While we can artificially breed for certain traits, there are certain other traits that are impossible to be selected because they do not exist within the gene pool. This is why you cannot breed a mouse with neon-orange fur; the only way to get that to happen is to physically mutate the DNA. This means that only a certain range of differences can occur before you hit the wall of homeostasis. Barring a fortuitous mutation (something not yet proven scientifically), we cannot claim species evolution.

And this indeed actually brings up an important counter-argument to Darwinian evolution. Homeostasis is a huge problem. We know that through artificial selection, no one has ever bred a new species (the closest anyone can come to that is through direct genetic mutation, in which case you’ve got artificial mutation). Furthermore, bacteria can reproduce very quickly.

For example, E. Coli can, in the right circumstances, double the size of the colony in 20 minutes. And E. Coli is also a very quick mutating bacteria. Unfortunately for the Darwinist, for all the mutation that E. Coli does, and for as quick as it can reproduce, no scientist has ever observed E. Coli evolve into a different species of bacteria. (Can you imagine the world-wide press attention if this did occur!?)

While E. Coli can mutate quickly to become drug resistant, it never becomes anything other than E. Coli. It’s no different than having various breeds of dogs: from the Great Dane to the Cocker Spaniel, all are still Canis Familiaris.

Thus, the rapid generations of bacterial reproduction, where we supposedly could see “evolution in real time” show us that millions of generations of bacteria have not evolved a single new species…yet we are to believe that animals, such as primates, who breed at a much slower rate, can have this much beneficial mutation in so short a time as 65 million years? The odds of this are astronomically faint.

But we’re not through with the mutative ability of E. Coli. The mutative ability actually appears to be a function of its design. That is, when the bacteria is stressed, it purposely turns on and off various genes, ensuring that the next generation will be different from the previous version; yet not so radically that the next generation is anything other than E. Coli.

This technique makes perfect sense from a design point of view. After all, if you have an organism in an environment where a specific drug can wipe out the entire colony, being able to spontaneously mutate various immunities will help at least some of the bacteria survive to reproduce another day. The colony continues to function because A) not all the individual organisms are wiped out and B) the colony remains E. Coli.

Indeed, we could argue the same thing on the human level too. No one disease will wipe out all of mankind since each of us are born with varying immunities. These “random” immunities ensure that there will be at least some survivors, even for bugs that do not yet currently exist. Since this fits perfectly into a design theory, it does not function as proof of Darwinian evolution. Indeed, if falls far short of what is needed to demonstrate Darwinism, making ID look all the more attractive.

3 comments:

  1. Oh, Peter, Peter, Peter,

    There is nothing wrong with the above illustration until you get to the term “new species.” In reality, no new species were created.

    Just what exactly do you think the definition of evolution is? Of course no "species" are created "in reality" by the change of a feature of a particular organism. "Species" is a categorizing tool that humans use to make sense to the degrees of difference between organisms. Typically humans definse species as whether or not tw oanimals can mate, but even that isnt always the case with species. And what of bacteria, who are asexual?

    We started with two types of the same species of bacteria—one resistant, the other not—and one type was killed off. This is identical, by the way, to what happened with the famous “peppered moths” illustration, where the light moths died off when pollution turned the trunks of the trees dark.

    And, in reality, it is no different than any adaptation. For instance, a wolf in the northern steppes of Russia may have longer hair than his brothers in more temperate climate. If we rounded up some random wolves, killed off certain wolves without a specific length of fur, we’d have the same result as with the peppered moths and the drug-resistant bacteria. It is, indeed, something that breeders have been doing for centuries—that is, artificial selection for certain traits within a species.


    So far so good, but a train wreck comes shortly thereafter:

    However, just as wolves with varying lengths of fur and moths with different colored bodies are still members of the same species, so too are drug-resistant bacteria strains in the same species as non-resistant bacteria.

    BWAHAHAHAHAHA! You are speaking complete nonsense. Species is a categorization tool, not some hard feature of a given organizm. You cant point out "species" in an organism like you can a wing, or an eyeball.

    The "species" of the E. Coli can be different between the resistant and nonresistant strains if we want them to be. Bioologists argue endlessley about which organizm belongs to which species. What Im saying is that its a category tool and is not a physically identifiable feature of the E. Coli.

    In other words, if you have E. Coli in a Petri dish, some of which is resistant and others not, every bacteria cell remains E. Coli. The drug-resistant E. Coli is not a different species.

    Yes, and if you have one flying mouse, and one non flying mouse, what you have are two mice. They are both the same "kind" of animal (to borrow a creationist term).

    Perhaps this can best be illustrated by moving the argument to the human level.

    "Human" isnt a species term, its a genus term. And again, its for categorizational purposes among biologists.

    Human beings naturally range in tolerability toward some diseases. Some people are immune to the effects of a particularly ravishing disease. Others are not. However, in no case would we consider an immune individual to be a different species than a non-immune individual.

    The key here is "would we consider" because these identifiers are all up to us and how we want to categorize the organisms we come across.

    People from each group are still human beings, capable of reproducing with each other, etc.

    Incidentally, there are many instances of different species reproducing with each-other to create hybrid species. Ever hear of a Liger?

    So, far from being an argument for species evolution, at most drug-resistant bacteria merely demonstrates the adaptability of an organism. The problem for the Darwinist is that adaptability is not a sufficient step toward species evolution to make species evolution viable.

    What, besides adaptability, constitutes "evolution" according to you, Peter? The ability for an organizm to "adapt" to the point where it meets an arbitrary criteria to be determined to be a "different species"?

    The variations possible in any organism are limited. While we can artificially breed for certain traits, there are certain other traits that are impossible to be selected because they do not exist within the gene pool. This is why you cannot breed a mouse with neon-orange fur; the only way to get that to happen is to physically mutate the DNA.

    Did resistance to antibiotics exist within the "gene pool" of the "crud" that you got?

    This means that only a certain range of differences can occur before you hit the wall of homeostasis. Barring a fortuitous mutation (something not yet proven scientifically), we cannot claim species evolution.

    So resistance to antibiotics is not a fortuitous mutation for the bacteria that you are infected with? And was the pepper moth scenario not a fortuitous mutation for the moths themselves?

    While E. Coli can mutate quickly to become drug resistant, it never becomes anything other than E. Coli.

    You mean that youve never seen it change into something other than E. Coli.

    Thus, the rapid generations of bacterial reproduction, where we supposedly could see “evolution in real time” show us that millions of generations of bacteria have not evolved a single new species…yet we are to believe that animals, such as primates, who breed at a much slower rate, can have this much beneficial mutation in so short a time as 65 million years? The odds of this are astronomically faint.

    Apparently you dont know the difference in degrees of variation that result in sexual reproduction (with the aforementioned primates) and asexual reproduction (with bacteria). Do you know why more advanced organisms have boy and girl parts, while less advanced organisms are all the same sex, and how it applies to your above complaint?

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  2. Aaron said:
    ---
    "Species" is a categorizing tool that humans use to make sense to the degrees of difference between organisms.
    ---

    He also said:
    ---
    Species is a categorization tool, not some hard feature of a given organizm. You cant point out "species" in an organism like you can a wing, or an eyeball.
    ---

    To quote Aaron's response: BWAHAHAHAHAHA! You're saying that Darwinian species-to-species evolution occurs...simply because scientists define certain organisms as a new species!!! BWAHAHAHAHAHA!

    In point of fact, speciation is another sticky problem for Darwinists. And it is true that scientists have disagreed with what the definition of a species is. For instance, Dobzhansky gave a strict definition of a species--one that could actually be scientifically tested. He defined it as: "That stage of evolutionary progress at which the once actually or potentially interbreeding array of forms becomes segregated into two or more arrays which are physiologically incapable of interbreeding."

    The problem with this definition is that A) scientists would have to actually prove that two organisms could not interbreed and B) many "distinct species" would suddenly not be "distinct species" any longer. For instance, Darwin's hallowed finches.

    Jonathan Weiner, to give one example, wrote of the finches on the Galapagos Islands: "Some of [the various finch species] look so much alike that during the mating season they find it hard to tell themselves apart." These "species" interbreed, have "hybrid" offspring that can also breed, etc. Obviously, then, the two starting finches are from different species....

    On the other hand, we might not wants such a strict definition. We could go with Mayr's more nebulous version: "Groups of actually or potentially interbreeding natural populations which are reproductively isolated from other such groups." That allows us more flexibility to define as unique species organisms that dare to interbreed anyway. Plus, it enables us to say Darwinism has proven the creation of new species! This fit's Aaron's view: "The 'species' of the E. Coli can be different between the resistant and nonresistant strains if we want them to be."

    But of course this merely demonstrates that Darwinian evolution is based on semantics, not science. Darwinian species evolution is simply defined into existence.

    Naturally, Darwinists would object if Creationists used this tactic. When Creationists do this, it's "faith", not science; when Darwinists do it, it's science.

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  3. > "particularly ravishing disease"

    You mean "ravaging"?

    ReplyDelete