Plesiosaur Day, 18 November 2004 - Some notes on the meeting
Discussion
An interesting discussion led by Arthur Cruickshank followed. The New Zealand 'elasmosaur' Mauisaurus differs from other elasmosaurs in their rod-like fused prezygapophyses which contribute to the stiffness of the neck. Cervicalisation of dorsal vertebrae appears to be a significant mechanism in the elongation of plesiosaurs necks. The distribution of binocular-shaped cervical centra was discussed, and the suggestion made that these are found only in the 'southern weirdos' - the rather aberrant upper Cretaceous Cryptoclidids such as Kaiwhekea and Aristonectes.
Richard Forrest presented Mike Everhart's photographs of gastroliths showing conchoidal fractures, which formed part of his talk at the 2004 SVP meeting. Mike has suggested that the fractures may be the result of high pressures within the digestive tract. There was a general consensus that it was more probable that the fracture pattern was incurred pre-ingestion. Another aspect of Mike's work on gastroliths is the investigation of their geological and geographical origin. This would be of considerable interest, as it would reveal aspects of plesiosaur behaviour and ecology not accessible by other methods.
Arthur closed the meeting by discussing the 'plesiosaur research renaissance' that has occurred since the 1970s. When, back in the '70s, Mike A. Taylor started a DPhil on plesiosaur heads he was discouraged by one senior palaeontologist on the grounds that there was no work worth doing specimens would not be made available, and/or that it was all taken up anyway by other workers.. It should be noted that Bev Halstead did not share this view, and instead shared his enthusiasm and his specimens. As Mike and others were to go on to show, this view was a rather grotesque misrepresentation and even today there are huge problem areas that require lots of work.