A 3D reconstruction of a reclining Psittacosaurus showing the long umbilical scar surrounded by distinctive scales that was identified by study team.
While the egg-laying nature of dinosaurs predicts a long belly button scar, this study is the first to support this hypothesis with fossil evidence
Laser-stimulated fluorescence (LSF) image of the whole Psittacosaurus specimen showing the location of the umbilical scar
Insets show the umbilical scar close-up, including the distinctive scales surrounding it (highlighted in blue in the line drawing)
“Using LSF imaging, we identified distinctive scales that surrounded a long umbilical scar in the specimen, similar to certain living lizards and crocodiles
'This specimen is the first dinosaur fossil to preserve a belly button, which is due to its exceptional state of preservation.'