Dinosaur eggs, embryos, and juveniles from the Upper Triassic and Lower Jurassic

Fossils with direct evidence on dinosaur reproduction behaviour and early ontogeny (development of embryos and hatchlings) are very rare, particularly those from deposits predating the Late Jurassic. We aim to reconstruct previously undescribed dinosaur embryos and juveniles from the Late Triassic-Early Jurassic of Poland and Sweden. The fossils to be scanned comprise: (1) eggshell fragments and infilled eggs from the newly discovered and oldest (latest Rhaetian) theropod nesting site (Skåne, Sweden), (2) eggs with probable theropod dinosaur embryos from an early Hettangian site (Holy Cross Mts., Poland), and (3) bones of a ?juvenile, basal theropod preserved in carbonate concretions from a mid-late Carnian site (Holy Cross Mts., Poland). By studying these specimens, we aim to cast new light on the ontogeny of some of the earliest large-sized theropod dinosaurs. Retrieving this information, however, will require the use of a powerful imaging technique.