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Conservapedia talk:Lenski dialog (view source)
Revision as of 03:50, June 27, 2008
, 03:50, June 27, 2008→Reply to comments in archive
:::: The resolution of the graphs are more than sufficient to communicate the results. If the figures didn't provide sufficient clarity for their purpose the authors would have also provided tables. For example, in figure 1 it's clear the culture shifted its growth pattern. In figure 2, one can see that the Cit+ cultures reach a higher density in the media, as indicated by the higher ODs. To a microbiologist, those results indicate that the Cit+ cells can utilize more of the nutrients in the media (in this case, citrate). --[[User:Argon|Argon]] 21:08, 26 June 2008 (EDT)
:::: The resolution of the graphs are more than sufficient to communicate the results. If the figures didn't provide sufficient clarity for their purpose the authors would have also provided tables. For example, in figure 1 it's clear the culture shifted its growth pattern. In figure 2, one can see that the Cit+ cultures reach a higher density in the media, as indicated by the higher ODs. To a microbiologist, those results indicate that the Cit+ cells can utilize more of the nutrients in the media (in this case, citrate). --[[User:Argon|Argon]] 21:08, 26 June 2008 (EDT)
:::: I'd like to chime in here and give some professional perspective. I am a molecular biologist -- if I asked him to, Prof. Lenski would send me a sample from his bacterial stocks (I have a -80 freezer and know how to work with E. coli). Let's assume for a minute that, like you, I strongly suspected the results of the paper (I do not, but that doesn't matter for this exercise). If this were the case, two of the routes I could take would be to re-analyze Prof. Lenski's data or replicate his experiments. In some cases, data and their analysis are complex, and re-analysis can yield different results than those the original author reached. This is the case for a large-scale association study, for example -- there are tons of data to analyze, and their analysis is not straightforward. In Prof. Lenski's case, however, the data are extremely simple, consisting primarily of 1) OD readings to measure fitness, and 2) colony counts.
:::: OD readings, or optical density readings, are obtained by pipetting a sample of cultured bacteria into a cuvette, sticking that cuvette into a machine, and writing down the number that pops up on a screen. Somewhere in a grad student's notebook (or in his/her computer) is a list of these numbers, and their average and range were presented in the PNAS paper at each generation in Figure 1 (similar data are presented in Figure 2 and Figure 5). So, in other words, the data you see in the paper *are all of the data* save for a second grade computation...which was probably performed by Excel. If you don't believe the data in the paper, then what do you expect to gain from seeing these "raw" data? There is so little to gain that I seriously doubt that PNAS would take such a request seriously.
:::: The meat of the paper, in Table 1, is a presentation of colony counts. These are obtained by another grad student picking up a bacterial culture plate, counting the number of colonies on it, and moving on to the next plate. Again, the raw data are what you see in the paper. What exactly are you expecting here, photographic images of all of the tens of thousands of plates they examined? That is just not done. Why would we go to that level of self-surveillance to please a small, vocal minority of people claiming fraud? The public's interest is not served by spending inordinate amounts of effort and money on this level of surveillance. If the science is correct, his experiment will be replicated.
:::: In sum, as others have tried to explain, there really isn't any more complex data for you to reasonably request. A slightly expanded list of numbers from what's in the paper won't get you anything if you already don't believe the data. And the scientific culture doesn't even come close to expecting photographic evidence of bacterial plates. Your best bet, if you really don't believe the results, is to get an outsider to try and replicate and/or confirm some portion of his results. The easy route would be to ask for a cit+ strain and its ancestor and see if they are indeed cit- and cit+. You could even sequence them to check if the cit+ strain is indeed an ancestor of the cit- strain, but while this would be a perfectly normal approach in a molecular biology lab with impressive resources, the entire concept of evolution is anathema to you, so I can't think of a reasonable criterion you would use to determine ancestry. If you wanted to go the hard route, you could obtain the ancestral strain and grow and measure them for years as Prof. Lenski's lab did.
:::: I hope this has been somewhat instructive for you in explaining why a request for "further data" will not bear fruit beyond the small amount of data that Prof. Lenski says he will make available. And why it is not reasonable to expect further data. I am more than happy to respond to questions or requests for clarification if you would like. -- [[User:Princetonian|Princetonian]] 23:50, 26 June 2008 (EDT)
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[[User:Philip J. Rayment|Philip J. Rayment]] 23:14, 26 June 2008 (EDT)
[[User:Philip J. Rayment|Philip J. Rayment]] 23:14, 26 June 2008 (EDT)
==Lead author won't answer simple, basic questions==
==Lead author won't answer simple, basic questions==