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Using Creation Science to Demonstrate Evolution 2: Morphological Continuity Within Dinosauria Philip J

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Using Creation Science to Demonstrate Evolution 2: Morphological Continuity Within Dinosauria Philip J Fayetteville State University DigitalCommons@Fayetteville State University Biological Science Working Papers College of Arts and Sciences Summer 2011 Using creation science to demonstrate evolution 2: morphological continuity within Dinosauria Philip J. Senter Fayetteville State University, [email protected] Follow this and additional works at: http://digitalcommons.uncfsu.edu/bio_wp Recommended Citation Senter, Philip J., "Using creation science to demonstrate evolution 2: morphological continuity within Dinosauria" (2011). Biological Science Working Papers. Paper 1. http://digitalcommons.uncfsu.edu/bio_wp/1 This Article is brought to you for free and open access by the College of Arts and Sciences at DigitalCommons@Fayetteville State University. It has been accepted for inclusion in Biological Science Working Papers by an authorized administrator of DigitalCommons@Fayetteville State University. For more information, please contact [email protected]. doi: 10.1111/j.1420-9101.2011.02349.x Using creation science to demonstrate evolution 2: morphological continuity within Dinosauria P. SENTER Department of Biological Sciences, Fayetteville State University, Fayetteville, NC, USA Keywords: Abstract baraminology; Creationist literature claims that sufficient gaps in morphological continuity Ceratopsia; exist to classify dinosaurs into several distinct baramins (‘created kinds’). Here, Coelurosauria; I apply the baraminological method called taxon correlation to test for creationism; morphological continuity within and between dinosaurian taxa. The results creation science; show enough morphological continuity within Dinosauria to consider most Dinosauria; dinosaurs genetically related, even by this creationist standard. A continuous Microraptor; morphological spectrum unites the basal members of Saurischia, Theropoda, Ornithischia; Sauropodomorpha, Ornithischia, Thyreophora, Marginocephalia, and Orni- Sauropoda; thopoda with Nodosauridae and Pachycephalosauria and with the basal Theropoda. ornithodirans Silesaurus and Marasuchus. Morphological gaps in the known fossil record separate only seven groups from the rest of Dinosauria. Those groups are Therizinosauroidea + Oviraptorosauria + Paraves, Tazoudasaurus + Eusauropoda, Ankylosauridae, Stegosauria, Neoceratopsia, basal Hadrosauri- formes and Hadrosauridae. Each of these seven groups exhibits within-group morphological continuity, indicating common descent for all the group’s members, even according to this creationist standard. (e.g. Strobel, 2004). This phenomenon is a problem, Introduction because it increases the already huge number of voters An alarmingly large portion of the population in North who believe that the creationist world view has scientific America and Europe rejects evolutionary theory (Mazur, validity and empirical support. 2005; Miller et al., 2006), and political opposition to the Because of this onslaught, it is imperative to demon- teaching of evolution in public schools is strong (Berk- strate that evolutionary theory is supported by empirical man et al., 2008; Branch & Scott, 2009). This opposition evidence. Towards this end, it is important to use is fuelled by practitioners of the discipline called creation methodology that is endorsed by creation science, so science, the endeavour to find physical evidence sup- that creation scientists cannot reject the results of such porting a literal interpretation of the biblical book of studies without rejecting their own research. Towards Genesis. Creation scientists publish technical accounts of that end, here I present a study using methodology their research in journals such as Journal of Creation and endorsed and used in baraminology, the branch of Creation Research Society Quarterly. The technical journals creation science in which organisms are classified into of creation science have limited readership, but research separately created ‘kinds’ (baramins). published therein is translated into ordinary language for Mainstream biologists and baraminologists alike con- the average reader in a vast, ever-growing collection of sider morphological continuity between species to be popular creationist literature that makes it appear that a evidence of genetic relatedness. Creationists long ago literal interpretation of Genesis is supported by scientific abandoned the concept of fixity of species, and for many studies. Some such books have even become best sellers decades, they have accepted that speciation occurs within baramins (Siegler, 1978). Baraminologists measure mor- Correspondence: Phil Senter, Department of Biological Sciences, phological continuity among species, accepting different Fayetteville State University, 1200 Murchison Road, Fayetteville, NC 28301, USA. species as part of the same baramin if they form a Tel.: +1 910 672 1304; fax: +1 910 672 1159; continuous morphological series. They classify different e-mail: [email protected] groups of species into different baramins if the groups are ª 2011 THE AUTHOR. J. EVOL. BIOL. JOURNAL OF EVOLUTIONARY BIOLOGY ª 2011 EUROPEAN SOCIETY FOR EVOLUTIONARY BIOLOGY 1 2 P. SENTER separated from each other by a gap in morphological scaling (CMDS). This is a technique in which the matrix continuity (Robinson & Cavanaugh, 1998; Wood, 2006, of character states is converted into a matrix of morpho- 2011). logical distances between taxa, and from that matrix of Mainstream biologists consider morphological conti- morphological distances, a set of three-dimensional coor- nuity through fossil lineages to be one of the main lines dinates is calculated. These coordinates are used to of evidence for macroevolution. Morphological continu- construct a three-dimensional scatter plot in which each ity between basal members of different lineages is one of dot represents a taxon, and the distances between dots the main lines of evidence that those lineages evolved represent morphological distances between taxa (Wood, from a common ancestor; for example, in recent years, a 2005). In a previous publication, I used CMDS to visualize plethora of transitional fossils linking major dinosaurian morphological distances between taxa within the dino- taxa have been discovered, increasing the known mor- saurian clade Coelurosauria. The resulting scatter plot phological continuity within Dinosauria and supporting appeared to show a continuous morphological spectrum the long-standing claim by mainstream biologists that all linking basal, Mesozoic birds (Archaeopteryx, Sapeornis and dinosaurs are descended from a common dinosaurian Confuciusornis) and several coelurosaurian groups (Senter, ancestor (e.g. Kirkland et al., 2005; Xu et al., 2006; 2010). I concluded that the study demonstrated the Choiniere et al., 2010; Yates et al., 2010). However, evolutionary relatedness of these groups with each other creationist literature claims that sufficient morphological and with basal birds in such a way as could not be discontinuity exists between dinosaurian taxa to effec- countered by creation science. However, baraminologist tively demonstrate special creation (e.g. Gish, 1995; Todd Wood subsequently pointed out that I had mistaken a Bergman, 2009). Here, I use the baraminological tech- mere visualization technique (CMDS) for a technique that nique called taxon correlation to test that claim. a baraminologist would accept as a test of genetic related- Taxon correlation begins with a matrix of character ness. Taxon correlation is a method that a baraminologist states for a set of taxa, e.g. the matrices of anatomical would accept as a test of genetic relatedness. Wood (2011) data that are routinely used by systematists in phyloge- restudied the Coelurosauria matrix using taxon correla- netic studies. The technique uses a Pearson correlation tion and found morphological discontinuity between coefficient to measure the morphological similarity three coelurosaurian groups: Oviraptorosauria, basal between taxa in the matrix. A detailed description is birds + Deinonychusauria and a group consisting of the supplied by baraminologist Todd Wood (2011): remaining coelurosaurs. A baraminologist could therefore infer that three baramins had been identified. Creationists Robinson & Cavanaugh (1998) introduced the Since then, the phylogenetic data matrix used in those taxon correlation method, wherein a Pearson correlation coefficient is used to estimate the relative similarity of two studies (Senter, 2010; Wood, 2011) has been enormously taxa. Beginning with a set of characters with discrete states, improved by an overhaul that included a vast number a square distance matrix D with elements dij representing of corrections and updates, detailed later. Most of the the per cent difference between the character states of taxa changes resulted from examination of a large number of i and j is calculated. The relative similarity of taxa i and j is specimens that I had not previously had the chance then estimated from D by calculating the Pearson correla- to study, at the Institute of Vertebrate Paleontology and tion coefficient for rows i and j of D. In theory, two taxa Paleoanthropology (IVPP) during a 2010 trip to Beijing. that are similar should have similar distances to the same Enough changes were made to justify a new phyloge- third taxon and should therefore exhibit positive correla- netic analysis and a new taxon correlation study with the tion. Negative correlation should occur between taxa that matrix, to see whether the technique would now identify are very different (i.e. taxa that are close to i will be far
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