Difference between revisions of "Flaws in Richard Lenski Study"
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[[Richard Lenski]] rejected a request to release his data to the public,<ref>See [[Conservapedia:Lenski dialog]].</ref> but the following serious flaws are emerging about his work<ref>Lenski et al., "Historical contingency and the evolution of a key innovation in an experimental population of ''Escherichia coli'', 105 PNAS 7899-7906 (June 10, 2008).</ref> even without a full disclosure of the data: | [[Richard Lenski]] rejected a request to release his data to the public,<ref>See [[Conservapedia:Lenski dialog]].</ref> but the following serious flaws are emerging about his work<ref>Lenski et al., "Historical contingency and the evolution of a key innovation in an experimental population of ''Escherichia coli'', 105 PNAS 7899-7906 (June 10, 2008).</ref> even without a full disclosure of the data: | ||
| − | 1. Lenski's "historical contingency" hypothesis, as specifically depicted in Figure 3, is contradicted by the data presented in the Third Experiment in Table 1 of his paper. | + | 1. Lenski's "historical contingency" hypothesis, as specifically depicted in Figure 3, is contradicted by the data presented in the Third Experiment in Table 1 of his paper. Figure 3 proposes a step-up in mutation rate to Cit<sup>+</sup> due to a historical contingency (potentiating mutation) occurring at about the 31,000th generation, yet the Third (and largest) Experiment in Table 1 shows Cit<sup>+</sup> arising just as often before the 31,000th generation as after. The abstract, in further contradiction with Figure 3, suggests that the historical contingency (potentiating mutation) occurred prior to the 20,000th generation. |
| − | 2. Lenski incorrectly included generations of the ''E. coli'' already known to contain Cit<sup>+</sup> variants in his experiments.<ref>Lenski incorrectly included generations 31,500, 32,000 and 32,500.</ | + | 2. Lenski incorrectly included generations of the ''E. coli'' already known to contain Cit<sup>+</sup> variants in his experiments.<ref>Lenski incorrectly included generations 31,500, 32,000 and 32,500.</refCit> Once these generations are removed from the analysis, the data disprove Lenski's hypothesis. |
3. Lenski's largest experiment (Third Experiment) failed to support his hypothesis with statistical significance. Even though this largest experiment was nearly ten times the size of his other experiments, Lenski did not weight this largest experiment correctly in combining his results. | 3. Lenski's largest experiment (Third Experiment) failed to support his hypothesis with statistical significance. Even though this largest experiment was nearly ten times the size of his other experiments, Lenski did not weight this largest experiment correctly in combining his results. | ||
Revision as of 14:36, July 13, 2008
Richard Lenski rejected a request to release his data to the public,[1] but the following serious flaws are emerging about his work[2] even without a full disclosure of the data:
1. Lenski's "historical contingency" hypothesis, as specifically depicted in Figure 3, is contradicted by the data presented in the Third Experiment in Table 1 of his paper. Figure 3 proposes a step-up in mutation rate to Cit+ due to a historical contingency (potentiating mutation) occurring at about the 31,000th generation, yet the Third (and largest) Experiment in Table 1 shows Cit+ arising just as often before the 31,000th generation as after. The abstract, in further contradiction with Figure 3, suggests that the historical contingency (potentiating mutation) occurred prior to the 20,000th generation.
2. Lenski incorrectly included generations of the E. coli already known to contain Cit+ variants in his experiments.Cite error: Closing </ref> missing for <ref> tag
References
- ↑ See Conservapedia:Lenski dialog.
- ↑ Lenski et al., "Historical contingency and the evolution of a key innovation in an experimental population of Escherichia coli, 105 PNAS 7899-7906 (June 10, 2008).
