Reasons to Believe

A Skunk by Any Other Name

Over the few short months I’ve been a visiting scholar at RTB, I’ve noticed the emergence of new terminology in the scientific literature to describe data and observations that don’t fit neatly into the evolutionary paradigm, but do comport with RTB’s creation model. Here are a few examples:

• Incomplete lineage sorting

• Accelerated evolution

• Gene conversion (GC) biased evolution

The chaotic patterns of genome comparisons between humans and chimps discussed in this issue (see “Will the Real Human Ancestor Please Stand Up?”) are an example of “incomplete lineage sorting.” The first occurrence of this terminology in the scientific literature was in 1996, but since then 166 articles have been published on the topic. The jargon sounds impressive but it masks damaging data for the evolutionary paradigm. Scientists with expertise in this area expressed the problem this way:

In concordance with the experimental evidences, this implies that there is no such thing as a unique evolutionary history of the human genome.1

In other words, the nice, neat story of humans descending from a common ancestor shared with chimps doesn’t match the experimental evidence. In general, however, the authors (of the 166 articles or so) fail to acknowledge the negative implications of the data.

“Accelerated evolution” is another new term in the scientific literature. It describes an unusually large number of changes in a region of DNA that is otherwise highly conserved––that is, it usually has few or no changes among a large variety of species. I discussed an example of accelerated evolution––HAR1––in a recent Today’s New Reason to Believe. So how does one explain a large number of changes in a region of DNA that does not seem to tolerate sequence changes? The typical evolutionary explanation assumes positive selection; that is, the mutations are so beneficial that the organisms carrying the mutations have a tremendous advantage over other members of the species without the mutation. They and their offspring out-compete the other members of the species without the mutation. But how does this selection get started if the original sequence is as highly conserved as HAR1 is? No explanation is offered.

Another interesting phrase that occurs––often in conjunction with accelerated evolution—is “GC-biased evolution.” When there are DNA-sequence changes that are observed between species (for example, changes in the gene sequence in humans and chimps), the changes often involve the replacement of A or T with G or C. This phenomenon is called GC-biased evolution. Much controversy surrounds this topic. Some studies say that the process is still going on2; other research suggests it is not.3 Some studies say the process occurs in some species but not in others.4 There are a variety of proposed mechanisms for this process, but no consensus.

One thing is common to these sophisticated phrases––once a term is coined, it’s often used but seldom explained. They become words that mask confusing concepts that aren’t amenable to normal reasoning processes. It’s like calling a skunk a rose in the hopes that it will be better-received because of its pleasant name. But a skunk by any other name still smells like a skunk.

However, these studies and the clever nomenclature they’ve spawned remain consistent with a model that posits a Creator using the same design templates with modifications to fashion new creatures as He sees fit.


Dr. Patricia Fanning

Patricia Fanning is an RNA biochemist with a PhD from North Carolina State University and formerly a consultant for software companies. As a visiting scholar to Reasons To Believe in 2011, she specialized in human embryology and evolutionary development and regularly contributed to RTB’s podcasts and publications.


Subjects: Biochemical Design, TCM - Biochemical Design

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NOTES

1. Ingo Ebersberger et al., “Mapping Human Genetic Ancestry,” Molecular Biology and Evolution 24 (2007): 2266–76.

2. Sol Katzman et al., “Ongoing GC-biased Evolution Is Widespread in the Human Genome and Enriched Near Recombination Hotspots,” Genome Biology and Evolution, advance access published June 21, 2011.

3. Laurent Duret et al., “Vanishing GC-Rich Isochores in Mammalian Genomes,” Genetics 162 (2002): 1837–47.

4. Ruth Hershberg and Dmitri A. Petrov, “Evidence that Mutation Is Universally Biased towards AT in Bacteria,” PLoS Genetics 6 (2010):e1001115–28.