SGER: Fringelites: Fossil Organic Molecules as a Proxy for Phylogeny in Paleozoic Crinoids

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SGER: Fringelites: Fossil Organic Molecules as a Proxy for Phylogenetic Analysis in Paleozoic CrinoidsW.I. Ausich and Y.-P. ChinOhio State UniversityEAR-0514203ABSTRACTFossil crinoids from LeGrand Iowa (Early Mississippian) are famous for their excellent preservation and characteristic species-specific coloration. Similar trends in color occur among crinoids from the Borden Group (Mississippian) of Indiana, as well as other locations across North America and Europe, but the reasons behind these trends and applications of this information have not previously been investigated. Inorganic pigments are usually the cause of unusual coloration in fossils, but in this case the species-specific coloration is due to organic molecules and is not entirely a relic of taphonomic processes. From hue, chroma and saturation observations alone, these crinoids sort into their morphologically determined phylogenetic groupings. Therefore, the molecules responsible for the colorations are candidates to function as a proxy for phylogenetic reconstruction. Identifiable basal and radial plates from multiple localities in North America and Europe will be tested for the presence of biomarker molecules. Specimens for analysis were selected to test for clade-specific biomarker distinctions at several taxonomic levels. Spectroscopic data of chromophoric organic molecules will be analyzed for aqueous extracts for several species of fossil crinoids and spectral data will be obtained by UV-Vis (Ultraviolet-Visible Light Spectroscopy), GC-MS (Gas Chromatography-Mass Spectrometry) and Fluorometry. Preliminary work on the organic molecules in Paleozoic and Mesozoic crinoids indicates the presence of substituted anthraquinone molecules. Complex molecules in the extracts will be analyzed for their utility as trackable characters for phylogenetic analysis. Additionally, two phylogenetic trees will be constructed for modern crinoids based on biomarkers and genetic markers (DNA), then compared to the historical understanding of modern crinoid phylogeny to test for congruence among the three trees to determine the applicability of using biomarker molecules in fossils as an aid in interpreting crinoid phylogeny. Ultimately, PIs' goal is to devise a means for establishing some correlation between a specific crinoid and a biomarker index unique to that species.