Reconstruction of a Lokiceratops rangiformis being surprised by a crocodilian in the 78-million-year-old swamps that would have existed in what is now northern Montana. Andrey Atuchin/Museum of Evolution hide caption
horned dinosaur
Scientists have identified a fossil of an herbivorous dinosaur, Psittacosaurus, being bitten by a mammal, Repenomamus. Gang Han hide caption
This fossil of a mammal biting a dinosaur captures a death battle's final moments
Scientists in Canada have diagnosed malignant cancer for the first time in a dinosaur, a Centrosaurus apertus from 76 to 77 million years ago. Sergey Krasovskiy/Stocktrek Images/Getty Images hide caption
Life reconstruction of Wendiceratops pinhorn. Danielle Dufault/PLOS ONE hide caption