Why do they have nutritive foramina in the vertebral centra?
The presence of nutritive foramina is used diagnostically to identify vertebral centra as being plesiosaurian. These formina are found on the underside of cervical and caudal, and on the sides of dorsal centra, and on the base of the neural canal. They are either tubes joining the neural canal to the underside of the spinal column, or openings into a space filled with some sort of specialised tissue within the body of the centrum. They occur on virtually all centra. What sort of metabolic system serves the entire body, and runs dorsally/ventrally rather than anterior/posterior?
