Classic Multidimensional Scaling isn’t the Sine Qua Non of Baraminology by Gordon Wilson

Phil Senter recently wrote a very revealing paper in the Journal of Evolutionary Biology entitled “Using creation science to demonstrate evolution: application of a creationist method for visualizing gaps in the fossil record to a phylogenetic study of coelurosaurian dinosaurs” (Senter 2010). The main objective in his research was to beat certain creation scientists at their own game. In short, he sought to demonstrate that classic multidimensional scaling (CMDS) used by baraminologists can be used to show evolutionary continuity among a variety of taxa traditionally held by mainstream creationists to be discontinuous because they were too different to be shoehorned into one created kind. I think his paper highlights a common misunderstanding about the conclusiveness of this test and the importance of understanding the underlying assumptions of CMDS.

Senter has “demonstrated” statistically the very thing I was worried about over the last year or two. My worry was the use of statistical baraminology in drawing holobaraminic conclusions particularly on groups that I suspected were polyphyletic. It seems other important criteria are not duly considered. In Senter’s study he uses CMDS to suggest evolutionary continuity between Archaeopteryx, early birds, and coelurosaurian dinosaurs. This was quite revealing since the vast majority of creationists over the last several decades assumed that dinosaurs of any kind are not phylogenetically related to birds. Notwithstanding Senter’s conclusions using baraminological tools, they’re not phylogenetically related, based on biblical and fossil evidence. Sure, all birds have feathers and many other structural and functional similarities (common design) but we also know from Scripture that there were, from the beginning, a variety of flying baramins including ravens and doves (Genesis 8:7, 12), pterosaurs, bats (Leviticus 11:19–20), and probably winged insects (Deuteronomy 14:11–20). Using evolutionary terminology; they are polyphyletic, i.e. completely unrelated to each other with regard to common descent. This is clear from Scripture. On Day Five, “[God] created every winged bird according to its kind” (Genesis 1:21). Neither Aves nor Aves plus coelurosaurs should be considered holobaraminic. The fossil record reflects this in that it shows distinct morphological gaps between the various orders of birds (Carroll, 1987). On Day Six God created the beasts of the earth, which included land dinosaurs. Even if many dinosaurs turned out to have feathers, but didn’t have wings, it can be maintained scripturally that they are not to be included in any of the created kinds of winged creatures simply because they were created on two different days.

Over the past few years I have become increasingly uncomfortable with the conclusions drawn from statistical baraminology. I initially didn’t balk at the method because it was showing patterns of similarity and dissimilarity. At first I thought it was pretty nifty because creationists had a quantitative method to show discontinuity. After I heard several presentations at the BSG annual meeting I began to feel baraminic distance correlation and multidimensional scaling was somewhat unnecessary when I saw it applied to whales. Were these necessary quantitative methods when they were telling us what was visually obvious to biologists and lay people alike? Just looking at whales, I could clearly see they were in two basic groups: baleen whales and toothed whales, and I didn’t need a quantitative method to convince me of that. Distinctly separated clusters in MDS scatter plots do not necessarily indicate different holobaramins. They could possibly represent higher level taxa above or lower taxa below the created kind.

I also began to be skeptical about the large size and disparity within these putative holobaramins. One example was the grass family Poaceae (Wood 2002), which included significant disparity exemplified by bamboo, cereal grains, and putting green grass. Even though I didn’t like it, I was at a loss to identify the fundamental blind spot I thought they had. At first I figured my objection was subjective because I was a splitter at heart (one who sees distinctions over similarities and errs toward chopping taxa into more and more groups). Was there an objective criterion (or criteria) that could be used to stop what I viewed as unchecked growth of baramins. Were these huge holobaramins simply larger patterns of similarity at higher taxonomic levels above “created kinds”? Would the creationist, Carolus Linnaeus, have derived similar groupings given the same data? Through his own detailed observations, Linnaeus saw natural groupings which he designated Kingdom, Class, Order, Genus, and Species (more taxa were added later). Though he assumed these groupings were unrelated, he still saw the need for more general groupings above the species level (he initially felt species was the created kind). He even classified orangutans in the genus Homo without assuming common ancestry with man. Creationists have never denied the presence of large taxonomic groups e.g. Animalia, Chordata, Aves, and Reptilia. But they don’t necessarily assume phylogenetic continuity when morphologic and molecular similarities are paraded before them as conclusive evidence of relatedness. Creationists have long held that remarkable similarity can be attributed to a same or similar design pattern conceived in the mind of the Creator. My fear is that statistical baraminologists have grown accustomed to using this technique to draw conclusions (albeit tentative) about holobaramins without looking hard at the differences in genetics, morphology, and behavior of the organisms in question. In addition, I also think they should first consider a number of important criteria described below before publishing decisive conclusions on any particular holobaramin. I strongly advocate that baraminologists should proceed slowly and should err on the side of small, well documented baramins that have fully met one or more of the following criteria.

1. Hybridization: Most creation biologists agree that the ability to interbreed and produce offspring (fertile or infertile) is the most robust criterion in determining whether or not two species belong to the same monobaramin (a subset of a holobaramin that have been shown to be related by common descent). Hybridization reveals fundamental similarities at a number of biological levels that would be difficult to demonstrate using other detailed analyses (Wood et al. 2003). McConnachie and Brophy (2008) also mention the value of using “multiple lines of evidence when delimiting holobaramins.” Of course fossil species lack the ability to breed due to obvious reasons so drawing conclusions and making pronouncements on the baraminological status of fossil taxa should be taken with a grain of salt. If the skeletal morphology between two “species” is very similar, I would still regard baraminological analysis as inconclusive. It is not due to faulty analysis with the available data; it is simply due to the paucity of relevant data. Often scientists abhor not knowing the answer and so they draw conclusions anyway based on highly tenuous and incomplete data. This is often true of creationists and evolutionists alike.
2. Synapomorphy Criterion (Wise 1992): Within the creationist paradigm a synapomorphy can be defined as any uniquely designed trait (internal or external) that is indicative of and shared by all members of the same holobaramin (Wilson 2010). In the absence of hybridization data, when testing for holobaraminic status of a particular group, if an apomorphy is not shared by all its members, one must ask if there is at least genetic evidence to suggest the apomorphy has the potential to develop in those presumed extant members lacking it. If a particular apomorphy is phenotypically and genotypically absent, holobaramic status should be tentatively denied (Wilson 2010). Wood et al. 2003 also states that since holistic datasets are unattainable, “datasets should be assembled from a balanced variety of morphological, ecological, and molecular data.” In the analysis of fossil data this cannot be done adequately. A lot of relevant soft anatomy, ecology, behavior, and genetics cannot be known at all or at best, cannot be determined with much certainty. It may be amazing how much can be ascertained through induction from skeletal evidence, particularly musculature, brain size, and shape, but at the end of the day, the level of certainty is lacking on particulars such as behavior, digestion, neurology, reproduction, and many other anatomical and physiological details. If these were known, it could reveal enormous disparity between the organisms in question. We may erroneously assume a high degree of overall similarity because of similar skeletal evidence.
3. Genomic Equivalence: It has been held by most creationists that genetic homology does not necessarily constitute common ancestry on the grounds that God can create different kinds with similar genomes. However, it is also true that organisms that have descended from a common ancestor will, of course, share an enormously high percentage of the same genes. How do we determine which similarity is due to common descent and which is due to common design? This is a very important question that requires much more understanding about the correspondence between genes and morphological traits. We need to elucidate all gene modules and/or gene networks responsible for morphological traits before drawing baraminic conclusions on genetic evidence alone. It seems reasonable that members of a created kind should have an exceedingly high degree of genomic equivalence. Because we know from Scripture that humans constitute a monophyletic group, we could use them as a rough measuring stick of genomic equivalence in analyzing other groups. We can ascertain the degree of genetic disparity within the human race and then use it as a gauge to approximate how much variation we could expect to find within other baramins. We should not expect to discover in certain humans additional genetic information which does not have an equivalent counterpart in the genome of other humans. Using this human standard we can analyze other extant organisms to see if they are similar enough to be in the same baramin. We should be extremely reticent to lump taxa together if we see significant differences in the genetic material (coding or noncoding) in one group but not in the other, even if the missing or extra genetic information constitutes a small percentage of the total. Differing chromosome number may not preclude the merging of very similar species because, despite karyological differences, the two groups may have a high degree of genomic equivalence. However, even this criterion is tenuous in the absence of hybridization data and conclusions should be expressly tentative.

One does not need to know the details of CMDS (classic multidimensional scaling) to see the faulty assumption that strong clustering of organisms necessarily reveals the identity of holobaramins. It simply doesn’t. As mentioned earlier, depending on the characters selected it may simply reveal higher apobaraminic groupings based on common design, monophyletic subsets of created kinds (monobaramins), or it may even stumble on the actual holobaramin. My point is that, apart from solid hybridization data, shared synapomorphies, and/or robust genomic equivalence, there is no surefire way of distinguishing between the actual holobaramins and larger or smaller groupings above or below them. Therefore, applying the term holobaramin to a group of organisms based solely on statistical tests is not appropriate.

Despite Phil Senter’s anti-creationist motivation, he doesn’t demonstrate evolution using a creationist method. This method spatially shows degrees of similarity and dissimilarity and may be useful taxonomic information, but it does not at all reveal any naturalistic mechanism for gradualistic transmutations from one potentiality region to another (Wood et al. 2003). He does, however, effectively expose a flaw in the assumptions of statistical baraminology; there is no way to know if the similarities or differences are really holistic based on this method alone. When a creationist methodology succeeds in lumping groups that contradict Scripture, such as early birds and coelurosaurian dinosaurs, it is time for creationists to “blow the whistle” and address some basic issues. The underlying assumptions of statistical baraminology should be better scrutinized, its role and utility in the baraminological toolbox should be seriously reconsidered, and strong conclusions should be avoided when other supporting data is absent.

Although baraminologists have noted that their conclusions are tentative, this fact is not emphasized enough. Though occasionally mentioned, it is generally assumed or subtly stated among colleagues. Consequently the tentative nature of science is not well understood by most lay readers. Because of a widespread tendency of the lay public to absolutize the pronouncements of science (both creationist and secular), it is paramount that creation scientists bend over backwards to make their conclusions overtly tentative particularly when certain organizations are eager to popularize their findings. Unless Scripture has clearly spoken on the matter it is essential that we are not hasty, that we have considered all relevant data, and that we have interpreted it circumspectly using sound biblical and scientific principles. The term holobaramin implies to most creationists that a definitive conclusion has been reached. If we are too inclusive with our holobaramins (family and above) without considering multiple lines of evidence, it could lead the lay public to make unwarranted generalizations among untested taxa (Wilson 2010).

Despite my critique of CMDS’s current role in baraminology, I want to make clear to my readers that I have brotherly love for and am a personal friend of all its practitioners in creation science. Though I am in disagreement with many of the conclusions that have been drawn, I greatly respect their intellect, diligence, productivity, commitment to the scriptures, and love for our Lord Jesus Christ. In the midst of having significant differences of opinion regarding this or other topics, it is paramount that all creationists strive to keep the unity of the Spirit through the bond of peace. We are a tiny minority in the scientific community, and nothing is more counterproductive in the advancement of young earth creation science than to allow differences of opinion to degenerate into sinful and sectarian hostilities toward one another.

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