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04-08-10, 10:53 PM #421Valued Senior Member
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I could be wrong, I could be right....
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04-09-10, 05:21 PM #422Banned
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In 1988, John Cairns at the Radcliffe Infirmary in Oxford, England, and a group of other scientists renewed the Lamarckian controversy (which by then had been a dead debate for many years).[18] The group took a mutated strain of E. coli that was unable to consume the sugar lactose and placed it in an environment where lactose was the only food source. They observed over time that mutations occurred within the colony at a rate that suggested the bacteria were overcoming their handicap by altering their own genes. Cairns, among others, dubbed the process adaptive mutation.If bacteria that had overcome their own inability to consume lactose passed on this "learned" trait to future generations, it could be argued as a form of Lamarckism; though Cairns later chose to distance himself from such a position.[19] More typically, it might be viewed as a form of ontogenic evolution.
There has been some research into Lamarckism and prions. A group of researchers, for example, discovered that in yeast cells containing a specific prion protein Sup35, the yeast were able to gain new genetic material, some of which gave them new abilities such as resistance to a particular herbicide. When the researchers mated the yeast cells with cells not containing the prion, the trait reappeared in some of the resulting offspring, indicating that some information indeed was passed down, though whether or not the information is genetic is debatable: trace prion amounts in the cells may be passed to their offspring, giving the appearance of a new genetic trait where there is none.[20]
http://en.wikipedia.org/wiki/Lamarckism
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04-09-10, 05:25 PM #423Banned
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04-09-10, 06:00 PM #424
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04-09-10, 06:18 PM #425Banned
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04-09-10, 06:41 PM #426Banned
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04-09-10, 06:55 PM #427Banned
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04-09-10, 06:57 PM #428Banned
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04-09-10, 07:14 PM #429Banned
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What you cannot understand about TOE is that it requires reproduction to alter chemistry through random mutations.
These experiments indicate that the species themselves altered their own chemistry to explain the rate beyond random variables. Further, the species were able to gain additional dna by will.
I do not want to lecture anymore.
Think on your own.
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04-09-10, 07:28 PM #430Banned
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04-09-10, 07:41 PM #431
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04-09-10, 08:02 PM #432
It's possible that stress, such as lack of food, can trigger increased mutation rates, this is an interesting evolutionary trait. Also, life forms like bacteria can borrow genetic material from other life forms.
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04-09-10, 08:28 PM #433
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04-09-10, 08:36 PM #434
It's known that some foods contain chemicals that act as mutagens. That is why most animals restrict themselves to a specific diet. If something is starving, it might go outside it's usual diet, and thus expose itself to more mutations than might otherwise occur. Indications are that other kinds of stress can trigger a similar phenomenon:
Abstract
Comparative biochemistry demonstrates that the metabolites, complex biochemical networks, enzymes and regulatory mechanisms essential to all living cells are conserved in amazing detail throughout evolution. Thus, in order to evolve, an organism must overcome new adverse conditions without creating different but equally dangerous alterations in its ongoing successful metabolic relationship with its environment. Evidence suggests that stable long-term acquisitive evolution results from minor increases in mutation rates of genes related to a particular stress, with minimal disturbance to the balanced and resilient metabolism critical for responding to an unpredictable environment. Microorganisms have evolved specific biochemical feedback mechanisms that direct mutations to genes derepressed by starvation or other stressors in their environment. Transcription of the activated genes creates localized supercoiling and DNA secondary structures with unpaired bases vulnerable to mutation. The resulting mutants provide appropriate variants for selection by the stress involved, thus accelerating evolution with minimal random damage to the genome. This model has successfully predicted mutation frequencies in genes of E. coli and humans. Stressed cells observed in the laboratory over hundreds of generations accumulate mutations that also arise by this mechanism. When this occurs in repair-deficient mutator strains with high rates of random mutation, the specific stress-directed mutations are also enhanced.
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04-09-10, 08:57 PM #435Banned
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Ah, cool, thanks

In all fairness, though- this could not apply to Jack_'s experiment cited.
I would consider the likeliest possibility to be that a few bacteria could eat lactose. Those that already had the gene survived and multiplied whereas those vast majority that didn't died and their population was quickly overwhemled and replaced by those few that could.
Also, alleles...
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04-09-10, 09:21 PM #436
Jack_:
Is this a roundabout way of saying you're a Lamarckian, who believes in inheritance of learned traits?
Do your Lamarckian views extend beyond bacteria to higher animals, or do they only apply to bacteria?
That's debateable and controversial.These experiments indicate that the species themselves altered their own chemistry to explain the rate beyond random variables.
There's no evidence of that, as far as I can see.Further, the species were able to gain additional dna by will.
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04-10-10, 08:46 AM #437
I have heard of a similar experiment with citrate. It's a long running and rigorous experiment with e. coli. Far from disproving evolution, it actually supports the theory. They know exactly which generation aquired one mutation, which was a prerequisite to metabolizing citrate. Then, another mutation happened, which together with the first, enabled e. coli to live off something it never could before. Only one of 12 original strains developed these two particular mutations.
Bacteria make major evolutionary shift in the lab
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04-10-10, 03:17 PM #438Moderator
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They wouldn't be in the same genus if they didn't have a common ancestor. That would violate the rules of taxonomy.
BTW...
* * * * NOTE TO THE MODERATOR * * * *
A couple of years ago it was decided to compromise on evolution denialism. Rather than dump it all in Pseudoscience or the Cesspool, one single thread was set up for it. This thread should be merged with that one. This makes evolution denialism the only form of crackpottery that is permitted on the science boards, and the permission is strictly limited.
Mod note: Done.Last edited by Hercules Rockefeller; 04-11-10 at 06:21 PM.
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04-10-10, 05:03 PM #439Banned
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04-10-10, 06:03 PM #440Banned
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Umm, this thread is not about denying TOE.
It is about showing it is not sufficient.
If you are declaring TOE as absolute truth, then let's see how that will turn out for you.
I have supplied documentation that indicates this insufficiency. You have not been able to refute this.
For you to exclude these experiments in logic is intellectual dishonesty.
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