NON-DESTRUCTIVE, THREE-DIMENSIONAL VISUALIZATION OF FOSSIL ECHINODERMS

Visualizing the interior and three-dimensional structure of exceptionally preserved fossils is a key step in resolving the morphology of extinct species, and can yield critical palaeobiological insights. Fossil echinoderms may be especially amenable to such analysis; well-preserved, three-dimensional specimens are known for many different groups. Several non-destructive scanning technologies exist for imaging high-resolution, three-dimensional anatomy. X-ray microtomography (XMT or micro-CT) is the most widely accessible; it is appropriate for visualizing millimetre- to centimetre-scale material, and is hence well-suited for the study of complete echinoderm fossils. Several examples will be presented, including ctenocystoids, edrioasteroids, eocrinoids, rhombiferans, and stylophorans. This 'virtual palaeontology' approach provides detailed information on articulations, openings and internal characters of fossil echinoderms; such features are of key significance for assessing competing morphofunctional and phylogenetic hypotheses, but can be difficult to study using conventional palaeontological techniques.