PROBLEM: Evolution is only a theory

If it seems that way to you, you didn't understand the experiment.The virus destroys all but a few individuals, which then form a new population. There's only two explanations for why some individuals survived:1) Bacteria possess an innate ability to resist this virus.2) Certain individuals had a mutation that allowed them to resist the virus.We know it can't be 1, because the bacteria are clones - they must be, that's a fact of how bacteria reproduce. If bacteria have an innate ability to resist this virus, they all would have. There would have been no visible effect when the virus was added.We know therefore that 2 must have happened by process of elimination. Mutation is the only logical explanation for the resistance to the virus. What the hell are you talking about? It's easy to get new fruit fly species in the lab, and it's been observed many times:

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5.3 The Fruit Fly Literature

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5.3.1 Drosophila paulistorum

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Dobzhansky and Pavlovsky (1971) reported a speciation event that occurred in a laboratory culture of Drosophila paulistorum sometime between 1958 and 1963...

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5.3.2 Disruptive Selection on Drosophila melanogaster

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Thoday and Gibson (1962) established a population of Drosophila melanogaster from four gravid females...

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5.3.3 Selection on Courtship Behavior in Drosophila melanogaster

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Crossley (1974) was able to produce changes in mating behavior in two mutant strains of D. melanogaster...

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5.3.4 Sexual Isolation as a Byproduct of Adaptation to Environmental Conditions in Drosophila melanogaster

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Kilias, et al. (1980) exposed D. melanogaster populations to different temperature and humidity regimes for several years. They performed mating tests to check for reproductive isolation. They found some sterility in crosses among populations raised under different conditions...

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5.3.5 Sympatric Speciation in Drosophila melanogaster

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In a series of papers (Rice 1985, Rice and Salt 1988 and Rice and Salt 1990) Rice and Salt presented experimental evidence for the possibility of sympatric speciation...

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5.3.6 Isolation Produced as an Incidental Effect of Selection on several Drosophila species

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In a series of experiments, del Solar (1966) derived positively and negatively geotactic and phototactic strains of D. pseudoobscura from the same population by running the flies through mazes...

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5.3.7 Selection for Reinforcement in Drosophila melanogaster

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Some proposed models of speciation rely on a process called reinforcement to complete the speciation process. Reinforcement occurs when to partially isolated allopatric populations come into contact. Lower relative fitness of hybrids between the two populations results in increased selection for isolating mechanisms...

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5.3.8 Tests of the Founder-flush Speciation Hypothesis Using Drosophila

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The founder-flush (a.k.a. flush-crash) hypothesis posits that genetic drift and founder effects play a major role in speciation (Powell 1978)... Dodd and Powell (1985) tested this hypothesis using D. pseudoobscura... Forty-four months after the start of the experiment (and fifteen months after the last flush) the populations were again tested. Once again, no postmating isolation was seen. Three populations showed behavioral isolation in the form of positive assortative mating.

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from Observed Instances of SpeciationAs you can see, it's almost trivial to cause speciation in fruit flies. Oh, I see. You don't know what the word "species" means. Why didn't you just say so instead of looking like an idiot?Here's the most useful definition, from the same link:

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Over the last few decades the theoretically preeminent species definition has been the biological species concept (BSC). This concept defines a species as a reproductive community.

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Dobzhansky defined a species as

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"... that stage of evolutionary progress at which the once actually or potentially interbreeding array of forms becomes segregated into two or more separate arrays which are physiologically incapable of interbreeding." (Dobzhansky 1937)

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So, in fact, not only are new species possible, they're quite common, as are mutations. You yourself have somewhere between 5 and 50. And speciation can be stimulated to the same degree of repeatability and accuracy. The mechanisms are quite well-understood in most cases. What you seem to be ignorant of is the fact that biologists use evolutionary theory to create those crops and vaccines. That's the greatest testament to the accuracy of the evolutionary model. Religion? Not by any definition of religion I'm aware of.

Well, I used "clones" in a loose sense of the term. If they were always clones, obviously evolution couldn't occur.But to as large an extent as possible, bacteria reproduce clonally. They only process besides mutation that introduced variety is the genetic exchange that most bacteria engage in sometimes. I'm not sure if "clone" refers to an exact copy, or just as exact a copy as possible. Theoretically all your somatic cells are supposed to be clones of each other, but obviously each of your cells is likely to have mutations caused by chemical or radioactive damage. Mutations are always possible. If the practical definition of "clone" doesn't allow for mutation then I suspect no organism could ever be referred to as a clone. I think that when biologists call something a clone, they're referring to reproduction that doesn't allow for the genetic shuffling of obligate sexuality, which as I understand it is the primary source of variety in sexual species.This message has been edited by crashfrog, 05-29-2004 03:07 AM

Presumably she has a few mutations; DNA replication is usually errorless but in an entire animal's worth of cells we would expect a number of mutations.If you wanted to be absolutely pedantic about it, Dolly is an exact replica of her mom except for:1) Whatever mutations were present in the mother's somatic cell from which Dolly's genetic material was extracted;2) Dolly's mtDNA, which were inherent to the zygote who's nucleus was replaced with the above;3) Any mutations accrued in Dolly's somatic cells through the course of her life (though we usually ignore these as they aren't passed on to offspring);4) Any epigenetic factors - things like coat pigmentation or structure of the iris, or more general things like exact height and weight, which are more environmentally influenced than genetic. Yeah, it's neat. There's a lot of mutation going on that simply isn't that relevant to evolution; for instance mutations that don't happen in germ cells (and therefore aren't usually passed on) or mutations that simply have no effect due to being on non-coding sequences or that, through redundancy, wind up coding for the same protien as before.Actually maybe I shouldn't say it isn't relevant; it's just that these mutations rarely, if ever, have any effect on the selective fitness of the organism, and so they generally slide into the background of our consideration, you know?This message has been edited by crashfrog, 05-29-2004 04:01 AM

I'm an ex-creationist, so I'll try and share what the deal was with me:For one thing, I was a teenager, and I suspect you've noticed that that's true of a lot of YEC's here. It's attractive to think that you have a kind of secret knowledge about the universe - something that only you and a select few seem to know. The fact that the vast, vast majority of scientists disagree with creationism makes it all the more attractive to some young folks.Also the species thing confused me. I never understood until much, much later how they got around the "hopeful monster" problem - if a species is defined as a reproductive community, then the first individual of a new species is going to be SOL because there's nobody else he can reproduce, right?Well, wrong, obviously, but it took me a while to learn to look at the problem from the aspect of population genetics and not individual physiology. Honestly if you asked me for advice about a high school biology curriculum, I'd start with population genetics and Mendel's experiments (the high-level behavior of heredity) before delving into the world of the cell (the actual mechanisms of heredity.) I think the way we teach biology is one of the greatest barriers to the understanding of evolution by laypeople.But I agree with your sentiment. Once you understand it, evolution is almost so simple that it just has to be accurate. So elegant.

You don't think shortened telomeres count as a kind of somatic mutation? If by "mutation" we mean "genetic change", it would seem to apply. Then again I supppose it's not a mutation in the traditional sense, right? Bah - never mind, I hate talking about what words mean.You're right, though, I had forgot about those. I had hoped by mentioning somatic genetic changes, I had covered all the bases, but apparently not. This message has been edited by crashfrog, 06-01-2004 07:14 AM

I didn't know about those, so thanks for bringing them up.