Eggshell characterisation of the early sauropodomorph dinosaur Massospondylus

While most known dinosaur egg consist of a hard calcitic shell, including their avian descendant, a recent study suggested early dinosaurs laid soft-shelled eggs. This result is quite controversial, mostly as it is based on the study of a single species, and also as the visible light Raman spectroscopy results presented are quite disputed. We propose to characterise the eggshell of another sauropodomorph dinosaur, Massospondylus, being of older geological age and earlier-branching position. Traditional method have resulted in vastly contradicting results, interpreting these egg as soft, semi-rigid, or hard-shelled. We propose to use synchrotron X-ray texture tomography to inspect these eggshell in fine details, allowing more in depth interpretation of their crystal lattice. This unexplored method in this field will provide important information to understand the reproduction mode in early dinosaurs.