Creationists evolve "new" arguments to explain genetic diversity

Guest post by David MacMillan.

David MacMillan is an author, engineer, and researcher who formerly wrote for Answers in Genesis before obtaining his degree in physics. He now writes about science and culture for Panda’s Thumb, the Huffington Post, and several other blogs.

In the buzz of excitement surrounding Opening Day at the Ark Encounter, the team of writers at Answers in Genesis continues their struggle to explain how all terrestrial life could have been shoved onboard the Ark and then exploded back out into millions of species in only a few dozen centuries. The more they write, however, the more difficult it becomes to make sense of their approach. Nathaniel Jeanson has a new post that further compounds my confusion.

One of AIG’s youngest writers, Jeanson sports an impressive Harvard degree in cell biology and has previously worked with the Institute for Creation Research. Given his degree, it must be assumed he has enough education to understand the subjects he is writing about. Jeanson appears sincere, and it is evident he believes his conclusions fervently. He has to know, though, that his arguments are completely detached from those conclusions. He writes with the awkward obfuscation of someone trying to defend a sinking ship while earnestly attempting to remain tenuously bound to the uncomfortable constraints of reality.

In past discussion, I’ve unpacked the hyperevolutionary claims of Ken Ham’s post-Flood speciation boom, as well as the implications of the whole ancestral-pair model. Young-earth creationists believe the entirety of the fossil record represents a single snapshot of the world ecosystem at a single point in time. All fossils are assumed to have been descended from the various “kinds” created during the Creation Week just a few centuries before the flood. Yet creationists have also committed to the notion that all this genetic diversity was preserved on the Ark and was reflected, however briefly, in the post-flood world.

The creationist model of genetics can be compared to a deck of playing cards that is continually being shuffled and dealt and cut. Each generation reproduces and shuffles the cards, producing new “hands” from the existing diversity in the deck. To creationists, speciation is the equivalent of cutting the deck and limiting a population to a smaller subset of the original deck of cards.

This approach presents enormous challenges. In their model, each of the “original kinds” was created with a “full deck” of genetic material, immediately being “cut” into new species that would end up being buried and fossilized in the Flood. But the Ark needed to preserve the “full deck” present at creation within each family; the post-flood world would then restart the process of splitting each of those decks into new species to form the diversity of life we see today.

The figure illustrates a series of problems that would not otherwise be readily apparent. For one thing, terrestrial creatures in the fossil record should not really look anything like modern terrestrial creatures, because they purportedly arose through a completely different set of speciation events. Of course, this doesn’t stop Answers in Genesis from touting “living fossils” ad nauseum. It is also unclear exactly how these creationists imagine that the genetic “deck” present at creation still existed at the flood. Presumably a sub-population from within each “created kind” avoided any sort of speciation in order to make it onto the Ark.

Still, the largest challenge remains clear: how do a couple of thousand ancestral pairs become millions of species in just a few thousand years, simply by shuffling and cutting the “deck” a few times?

One thing is for sure: it has nothing to do with the life cycle of amphibians. The life cycle of a frog from egg to tadpole to adult is fascinating to be sure, but it has nothing whatsoever to do with the process of speciation. Yet, astoundingly, this is what Jeanson leads with.

To skeptics of the Scriptures, producing so many species in such a short time span—short as compared to the evolutionary time span—seems implausible.

These skeptics forget the evidence right under their nose[s]. While the origin of over 30 living cat species might appear to require significant morphological changes, visible variety of a much greater magnitude can arise in an even shorter frame of time. For example, a frog begins its life as a fertilized egg—as single cell. No limbs, head, eyes, tongue, long toes, and so on are visible at the single-cell stage. Yet, in the process of development and maturity that spans less than 3 years, these anatomical features are formed. This progression from a single cell to an adult frog represents far more visible change than the process of forming new species from the kinds on board the Ark.

It is hard to imagine an argument more utterly irrelevant, surpassing even the inanity of “Why are there still monkeys?” and verging on statements like “I’ve never seen an ape becoming a person!” Why does Jeanson, a PhD biologist, make it—especially when he immediately repudiates it?

I can only assume that he is seeking some example that sounds even vaguely similar to what he wants to prove. It’s like a lawyer who says, “I couldn’t possibly tell the jury that the victim told the police she wasn’t hurt, because that would be hearsay” and hopes it “sticks” even when the judge rules his statements irrelevant.

With undeterred persistence, Jeanson leaps from one lily pad of irrelevancy to the next by bringing up “DNA differences” in order to lead into a discussion of mitochondrial DNA clocks.

Can enough genetic diversity arise in a few thousand years to make the young-earth speciation model work? Today, millions of DNA differences separate species from one another. How can millions of DNA differences arise in a few thousand years? To the skeptic, the answer is simple—millions of DNA differences can’t.

Ridiculously misleading. Speciation indeed involves numerous changes in DNA, but at a scale orders of magnitude higher than the number of DNA differences that typically exist between individual members of one species. In this paragraph, Jeanson illustrates a prime example of a tactic common among creationists. Humans have three billion base pairs, so variation of 0.4 % becomes “millions” of differences at the base pair level. Creationists cite these numbers without any comparison or explanation of what they represent, since they know that their audience will not have enough background information to recognize the fallacy.

Jeanson could have explained the significance of these numbers. Instead, he changes gears mid-argument, bringing up mitochondrial DNA. Mitochondrial DNA is not subject to sexual recombination and thus provides a genetic clock to identify divergence time between two lineages. It is a subject about which creationists already have existing discussions, so Jeanson simply slides into these talking points despite the fact that DNA differences in mitochondrial DNA have absolutely nothing to do with nuclear DNA differences or speciation.

His line of argument can only be compared to an earnest shotgun-inspired Gish Gallop. Mainstream science claims that there’s not enough time for speciation, and mainstream science also claims that there’s not enough time for mitochondrial DNA differences to accumulate—so if we can cast doubt on the latter claim, then maybe the general confusion will carry over to the former one.

Without explaining why he brought up mitochondrial DNA, Jeanson switches gears once more and spends several paragraphs explaining that two members of the same species can have numerous DNA differences. This fact has nothing to do with the issue at hand, but somehow he thinks it does—or at least thinks it is relevant:

Copying errors are unable to explain the vast amount of [nuclear] DNA differences we see today because the vast majority of these differences are not the product of error, but of deliberate design. Similarly, it appears that God created nuclear DNA differences in the animal kinds as well. Genetic calculations suggest that God created tens of millions of DNA differences from the start.

What good does this do? He tells us:

Once the animals stepped off the Ark, their reservoir of DNA differences could have easily translated into a massive amount of morphological change.

This claim is clear, concise, and well-defined. Jeanson could go on to provide evidence for this claim or make verifiable predictions associated with it. For example, he could point to observed speciation events matching this model (if any existed) or he could predict a series of conditions under which a single pair of organisms can produce rapid multiple branching speciation in its offspring.

But he doesn’t.

In a final topic change, Jeanson starts talking about junk DNA. Non-coding DNA has absolutely nothing to do with the generation of new species; it is just another tangentially related topic where prepared talking points already exist. After repeating the various prepared discussion concerning “junk” DNA, he claims:

Since DNA now appears to be extremely functional, it would seem that the production of a new species would simply require a few DNA differences to arise.

This statement is absurd, unsubstantiated, and demonstrably false speculation. It is irresponsible at best.

What we have here is, I suppose, precisely what would be expected from someone who has a high level of familiarity with the subject and yet knows he has no chance of making a cogent argument. He just goes through a bunch of tangentially related topics, making a bunch of fact statements that are usually not entirely wrong, and then declares victory. Even though none of his explanations have anything to do with the mechanism for turning a few thousand animal pairs into millions of species in just a few dozen centuries, he concludes:

With millions of DNA differences—massive amounts of DNA variety—encoded into each kind from the start of their existence, the potential for speciation is mind-boggling. Combined with the fact that species can recover enormous population sizes in very short amounts of time, in addition to the fact that the vast majority of DNA sequences within a creature appear to be functional, these results demonstrate that millions of species in a few thousand years is not only plausible, it is also probable.

The claim that millions of DNA differences constitute “massive amounts of DNA variety” capable of generating thousands of speciation events is ridiculously wrong.

There is something mind-boggling here, all right. But it is not the potential for post-flood speciation. What boggles my mind is the ability of creationists to talk so much and yet say so very little.