Controversy Over a Visible Evolutionary Shift In Bacteria

To get an idea of the evolutionary presuppositions and interpretations the article is filled with, take a look at the first web comment it inspired:

More proof, if any were needed, that Darwin is right, and the God squad wrong. But it won’t make any difference to them . . . the truth is to be found in the holy texts, and not laboratories.

The New Scientist article, “Bacteria Make Major Evolutionary Shift in the Lab,” starts off, “A major evolutionary innovation has unfurled right in front of researchers’ eyes. It’s the first time evolution has been caught in the act of making such a rare and complex new trait.” But let’s take a look at this “evolutionary innovation,” this “rare and complex new trait” that the evolution god has “created.”

The story starts 20 years back at Michigan State University. Evolutionary biologist Richard Lenski took a single E. coli bacterium and propagated it, using its descendants to “found” 12 laboratory populations that have continued to grow since then.

Lenski’s been watching in the meantime—perhaps not always literally, but nonetheless observing as 44,000 generations of the E. coli have come and gone. Every 500 generations, Lenski pulled a sample of each E. coli population and put it in the deep freeze.

During all this time, the bacteria has mutated (as expected) and “evolved”—and here, of course, is where the controversy begins.

According to Lenski, most of the evolution in the populations was the same: larger cells and faster growth rates, as well as lower “peak population densities,” occurred in each of the populations.

The most notable change happened in just one of the populations: around the 31,500th generation, the bacteria “suddenly acquired the ability to metabolise citrate,” which E. coli cannot normally process. The E. coli that developed the citrate-processing ability then increased in population size and diversity.

Lenski figures that this “citrate-plus” ability was an unusual circumstance.

Lenski figures that this “citrate-plus” ability was an unusual circumstance. New Scientist explains, “either it was a single mutation of an unusually improbable sort, a rare chromosome inversion . . . or else gaining the ability to use citrate required the accumulation of several mutations in sequence.”

But Lenski wondered: would that same ability have evolved again? He has since “replayed” the evolution from frozen samples, but only the original population of E. coli has supposedly re-evolved the citrate-processing capability, and only from generation 20,000 or later. Thus, Lenski and his team have concluded that something occurred in the single population after generation 20,000 that enabled the citrate processing around generation 31,500.

The New Scientist article closes:

Lenski’s experiment is also yet another poke in the eye for anti-evolutionists, notes Jerry Coyne, an evolutionary biologist at the University of Chicago. “The thing I like most is it says you can get these complex traits evolving by a combination of unlikely events,” he says. “That’s just what creationists say can’t happen.”

While Darwinists are quick to claim this experiment as support for “evolution” (in reference to full-blown, molecules-to-man evolution), let’s first take a step back and review what “evolution” is, along with the different narratives evolutionists and creationists tell.

“Evolution” (in a biological sense), strictly defined, is simply a change in a population’s gene frequencies over time (as generations come and go). Thus, even mutations that remove genetic information can spread if they confer some reproductive and survival advantage.

Even mutations that remove genetic information can spread if they confer some reproductive and survival advantage.

Thus, any time a biological population is observed undergoing any sort of heritable change—even a change that keeps genetic information constant or that reduces genetic information—it is “evolution” in action. This evolution “before our very eyes” is usually then touted as proof for molecules-to-man evolution, even though the latter would require a massive increase in genetic information. It’s the old “bait and switch” tactic, as “evolution” shifts meaning from experimentally shown change to unobservable molecules-to-man change.

So what’s really going on in Lenski’s experiment? Actually, nobody really knows! Lenski’s team is still working to understand “just what that earlier change was, and how it made the . . . mutation possible.” They will likely be analyzing the genome of the original E. coli parent and the genomes of its “evolved” offspring. The citrate-processing ability may be due to the activation of a latent function or a beneficial (but not information-gaining) mutation that allows citrate processing.

It’s important for us all to remember that when we read science news that seems to “confirm” evolution, it’s never a true threat to the biblical worldview and the creation account because God’s Word never changes but man’s fallible ideas do.

Furthermore, creationists are just as interested in figuring out how the citrate-processing ability came about in this batch of E. coli. AiG’s Dr. Georgia Purdom is studying the research for an upcoming semi-technical article in the journal Answers In Depth.