Are the processes of mutation and natural selection sufficient to create “new information” in a genome?
There’s little debate that mutation and natural selection can allow a species of organism to develop traits that allow it to survive and reproduce in a given environment better than the original organism of that species could. Creationists tend to call this “micro-evolution.”
Creationists propose that micro-evolution is not sufficient to produce “macro-evolution,” which is usually defined as a “kind” becoming another “kind.”
Biologists usually state that there is no known limit to the accumulation of these changes, and so the line between “micro” and “macro” evolution is a false one. Creationists, on the other hand, state that “new information” is required to change one “kind” to another.
Because of this discrepancy in the requirements for what qualifies as evolution, there are going to be arguments about whether the observed changes in organisms’ genomes are evidence of evolution or not. Specifically, the definition of “new information” will be critical. To the majority of biologists, an organism’s ability to do something it couldn’t before is sufficient to show that new information has been added to a genome; creationists will argue that some traits can be added by either reactivating dormant genes, or integrating plasmids from other organisms. While the information may be new to the organisms, the creationist’s point is that no new information can be added to the whole biosphere’s collection of genomes, regardless of whether it’s passed between organisms.
I’ll limit the examples to those where an organism acquired new genetic traits based on mutation and selection of the existing genome.
It should be noted that this discussion will not change the nature of the science itself. It’s common to hear the phrase “That’s based on an assumption of millions of years,” as if that’s an a priori assumption made by researchers. In fact, it’s based on a mountain of data from geology, physics, biology, and nearly every other discipline, which, taken in toto, is simply overwhelming in its support for an old universe and the process of evolution. But of course, in internet discussions that level of investigation never happens the way it does in scientific circles, which is why every major scientific organization in the world has issued its own statement supporting evolution. You can read about a hundred of them here: http://ncse.com/media/voices/science
Last, before we talk about a few examples, I would like to ask creationists to make a prediction based on their own premises. If no new information is added to genomes, and as I’ve heard many times, that only degradation can happen because of Adam’s sin, it suggests that at some point in the future, species’ genomes will become so degraded that the species will simply fail to reproduce and lineages across the globe will simply end. I would be very interested in reviewing some creationist research that attempts to quantify the rate of degradation. It would be a very powerful prediction that evolution couldn’t make, and if it came to be proven accurate, would be enough to force researchers around the globe to reassess everything about evolution. It would be a fantastic triumph for creationism. I’m sure someone is working on it even as I write this.
Let’s pick an example. It’s a famous one, so I anticipate everyone in the discussion looking up what pundits on either side have said and parroting them here. That’s not much of a discussion, but I don’t see any other way of doing it. None of us here are trained evolutionary geneticists, so we will be relying on people who are. Please do the courtesy of referencing the original paper you’re using to make a point.
Lenski’s e coli experiment. Lenski has published literally dozens of papers on the evolution of his e coli genome, the latest of which is at Science http://www.sciencemag.org/content/342/6164/1364
(unfortunately unavailable without a subscription). Fortunately, there’s a not-terrible summary of his work on Wikipedia http://en.wikipedia.org/wiki/E._coli_long-term_evolution_experiment
. Creationists have been writing about his work for almost as long as he’s been publishing it, so we should have lots and lots and (ad nauseam) lots of material on both sides to wade through.
Here’s one of the key findings: “In 2008, Lenski and his collaborators reported on a particularly important adaptation that occurred in the population called Ara-3: the bacteria evolved the ability to grow on citrate under the oxygen-rich conditions of the experiment. Wild-type E. coli cannot grow on citrate when oxygen is present due to the inability during aerobic metabolism to produce an appropriate transporter protein that can bring citrate into the cell, where it could be metabolized via the citric acid cycle.”
And: “Examination of samples of the population frozen at earlier time points led to the discovery that a citrate-using variant (Cit+) had evolved in the population at some point between generations 31,000 and 31,500. They used a number of genetic markers unique to this population to exclude the possibility that the citrate-using E. coli were contaminants.”
To kickstart the discussion, here’s what creationists tend to say: http://www.evolutionnews.org/2012/11/rose-colored_gl066361.html
Now we will get into the discussion (perhaps, argument) of what constitutes “new information” and whether that is the proper method to measure the legitimacy of evolution.