Vertebra would have been joined together to form the spine of the animal in question. It is rare to find a fossil of the entire vertebral structure, rather than part of the vertebrae. We can gain information about an animal by examining its vertebrae – for instance, marine animals had different vertebrae to land dwelling animals.
Mosasaurs were large, marine reptiles – from the Late Cretaceous Period. They became extinct around 66 million years ago – along with all other non avian dinosaurs. This was in the Cretaceous-Paleogene extinction event, which was caused by an asteroid colliding into earth.
