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Conservapedia talk:Lenski dialog (view source)
Revision as of 00:46, June 30, 2008
, 00:46, June 30, 2008→Lead author won't answer simple, basic questions
:::::::This is utterly beside the point, however, because the importance of this recent paper does not depend on the detail of the strain being Cit+ - it could have been the development of a toxin, or some other event that led the new strain to be markedly, phenotypically different from its ancestors in some way. The importance lies in the work that was done to sketch out the outline of how the new trait developed, and in the re-development of the same trait during a re-running of the experiment from ancestral stock.<br />
:::::::This is utterly beside the point, however, because the importance of this recent paper does not depend on the detail of the strain being Cit+ - it could have been the development of a toxin, or some other event that led the new strain to be markedly, phenotypically different from its ancestors in some way. The importance lies in the work that was done to sketch out the outline of how the new trait developed, and in the re-development of the same trait during a re-running of the experiment from ancestral stock.<br />
:::::::Is it interesting that the trait seen in Lenski's E. coli is the metabolism of citrate under aerobic conditions? Yes. Is it remarkable? Yes, since you can count the number of E. coli strains that can do this on one hand. It's so wild and crazy that it might lead one to question whether the bacteria involved should even be called E. coli anymore - it's that striking a difference from 'normal' E. coli behavior. Was the development of the Cit+ strain an accident? Entirely. Would another Cit+ strain arise if the experiment was completely restarted from 1988? Almost certainly not - Lenski's data suggests that this is a staggeringly unlikely event, dependent on a series of merely overwhelmingly unlikely events. Did Lenski wish to develop a Cit+ strain from the beginning? No man can know the inner mind of another, but I would bet the farm that he didn't see this coming. If I were designing an E. coli breeding scheme with the stated purpose of selecting for a Cit+ mutant, I can think of much, much, much better ways to do it than this experimental protocol. The Cit+ trait is a novelty - an interesting one, one that is remarkable because of its rarity, one that resonates - but the value of the research does not depend upon it. --[[User:Brossa|Brossa]] 17:33, 29 June 2008 (EDT)
:::::::Is it interesting that the trait seen in Lenski's E. coli is the metabolism of citrate under aerobic conditions? Yes. Is it remarkable? Yes, since you can count the number of E. coli strains that can do this on one hand. It's so wild and crazy that it might lead one to question whether the bacteria involved should even be called E. coli anymore - it's that striking a difference from 'normal' E. coli behavior. Was the development of the Cit+ strain an accident? Entirely. Would another Cit+ strain arise if the experiment was completely restarted from 1988? Almost certainly not - Lenski's data suggests that this is a staggeringly unlikely event, dependent on a series of merely overwhelmingly unlikely events. Did Lenski wish to develop a Cit+ strain from the beginning? No man can know the inner mind of another, but I would bet the farm that he didn't see this coming. If I were designing an E. coli breeding scheme with the stated purpose of selecting for a Cit+ mutant, I can think of much, much, much better ways to do it than this experimental protocol. The Cit+ trait is a novelty - an interesting one, one that is remarkable because of its rarity, one that resonates - but the value of the research does not depend upon it. --[[User:Brossa|Brossa]] 17:33, 29 June 2008 (EDT)
::::''"You continue to dwell on the semantics of 'goal' as though it has some particular relevance to the validity of the research presented in Lenski's latest paper. The experiment was started in '88 to track the evolution of a population of E. coli."''
::::I am trying to get answers to some simple, basic questions about the experiment. Is there something wrong with that?
::::Also, the "semantics" -- as you call them -- of "goal" are very important. A lot of people have the mistaken idea that a goal is necessarily an expected result or is necessarily an intended result. Just going around telling people that the Cit+ evolution was not a goal can be very misleading.
::::''"The purpose of the 'glucose cycling' is to provide the bacteria with an environment that will favor those mutants that are better able to exploit a limited critical resource."''
::::That statement is too vague.
::::''"The glucose cycling does not inherently favor the development of a Cit+ strain any more than it favors other potential solutions to the problem - like secreting a toxin to kill your competitors, or faster reproduction to outbreed them, or photosynthesis, or cannibalism, or what have you."''
::::The glucose cycling gives an especially big advantage to Cit+ bacteria because they have something to eat after the glucose supply is exhausted whereas their Cit- neighbors do not.
::::''"Citrate is present in the growth medium as a chelating agent and buffer -- it was not added solely to serve as a potential carbon source, although it is one."''
::::Yes, I know it is there as a chelating agent -- but I also want to know if Cit+ evolution was a goal (again, a goal does not have to be an expected result and can even be an unlikely result) and if favoring Cit+ evolution was a purpose or one of the purposes of the glucose-cycling (I also would like to know if there were other purposes of the glucose-cycling and exactly how any other purposes work). The fact that Cit+ evolution was observed once previously adds to my hunch that it was a goal. Also, the bacteria already had the ability to metabolize citrate and just needed to evolve a way to pass citrate through the cell wall.
::::''"You seem to believe that the reason that Lenski is getting acclaim for this research is just that has isolated a strain of E. coli that can metabolize citrate under unusual conditions"''
::::Well, he is getting a lot of acclaim for it, isn't he? The paper has been widely ballyhooed all over the Internet. The Internet has several articles and hundreds of comments about it.
::::''"If you could clearly state what your suspicions are"''
::::Right now I am just trying to understand the experiment. [[User:LarryFarma|LarryFarma]] 20:46, 29 June 2008 (EDT)
:::::::''"I'm sorry, I thought you were asking for help."'' You call that "help"? All you did was clutter up this talk page with your irrelevant "hypothesis" idea. With friends like you, who needs enemies? [[User:LarryFarma|LarryFarma]] 10:34, 29 June 2008 (EDT)
:::::::''"I'm sorry, I thought you were asking for help."'' You call that "help"? All you did was clutter up this talk page with your irrelevant "hypothesis" idea. With friends like you, who needs enemies? [[User:LarryFarma|LarryFarma]] 10:34, 29 June 2008 (EDT)
::::::::When did I call it help? I said that I thought you were asking for it. In any event Brossa seems to have clarified the situation.--[[User:British_cons|British_cons]] [[User_talk:British_cons|(talk)]] 11:38, 29 June 2008 (EDT)
::::::::When did I call it help? I said that I thought you were asking for it. In any event Brossa seems to have clarified the situation.--[[User:British_cons|British_cons]] [[User_talk:British_cons|(talk)]] 11:38, 29 June 2008 (EDT)