Evolution in E. Coli

So I'm really getting my E. Coli fix. The Nondiscovery Blog has a nice post regarding Michael Behe's refusal to accept the conclusions of Lenski's recent paper in PNAS on demonstrated evolution in E. Coli. Rather, Behe thinks the evidence shows that random mutation breaks more beneficial genes than it makes and that there are enormous odds in developing a series of mutations, each one neither beneficial nor detrimental, yet resulting in an overall benefit at the end of the series. The likelihood of this occurring is rare, according to Behe, and so speaks against evolution rather than for it.

Yet Behe is shortsighted or is incapable of thinking outside the box. It is precisely these kinds of questions that beg for further exploration rather than just turning off the lights and going home with your bible tucked under your arm. As Carl Zimmer notes, there are several ways in which E. Coli transfers genetic information. More to the point, despite the odds, evolution did occur within Lenski's jars of E. Coli and it did occur in slow stages. Whether it was a vertical, stepwise occurrence (which is the only kind that Behe can conjure in his mind), or by a combination of horizontal and vertical information transfer, we don't yet know. However, if Behe wants to play the numbers game, he should allow that there might be several mechanisms at work that, in the aggregate, support evolution via natural selection acting on random mutation. After all, that is what Lenski's long running experiment shows.

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