The imagery on this page was the basis for a paper entitled Digital Preparation of a Probable Neoceratopsian Preserved Within an Egg, with Comments on Microstructural Anatomy of Ornithischian Eggshells, by A.M. Balanoff, M.A. Norell, G. Grellet-Tinner, and M.R. Lewin (Naturwissenschaften Early View). The abstract is as follows:

       We describe the first known embryo of a neoceratopsian dinosaur, perhaps the most ubiquitous        Laurasian group of Cretaceous dinosaurs, which is preserved completely enclosed within an egg. This        specimen was collected from Late Cretaceous beds of southern Mongolia,        which commonly preserve fossils of the neoceratopsian, Yamaceratops        dorngobiensis. The small egg was scanned using high-resolution X-ray        computed tomography (HRCT) and digitally prepared from the matrix. The        preserved and imaged elements support a diagnosis of the embryo to        Neoceratopsia, and allow preliminary observations of ontogenetic        transformations within this group. The addition of an embryo also adds another important data point        to the already impressive postnatal ontogenetic series that are available for this clade.

This specimen was made available to the University of Texas High-Resolution X-ray CT Facility for scanning by Dr. Matthew Lewin of the UCSF Medical Center. Funding was provided by Dr. Lewin.

Egg and scan

This specimen was scanned by Matthew Colbert on 3 February 2004 along the 'coronal' (long) axis for a total of 1296 slices. Each 1024 x 1024 pixel slice is 0.036 mm thick, with an interslice spacing of 0.036 mm and a field of reconstruction of 32 mm.

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