The long neck of the plesiosaur is a mysterious adaptation for which many hypotheses have been proposed. The most recent suggestion comes from Dr Leslie Noe of the University of Cambridge . After examination of the neck vertebrae of the long-necked plesiosaur Muraenosaurus, whose name translates as ‘Moray eel lizard’, Dr Noe concluded that the natural position of the neck was a downwards curve towards the sea-bed. The ability of the neck to flex in other dirctions was limited and the swan-like pose often seen in restorations of plesiosaurs (pictured) was impossible. Also impossible was the ability to raise the neck out of the water in an arc. The research was originally presented in 2004 at the 52nd Symposium of Vertebrate Palaeontology and Comparative Anatomy, Leicester, England (see abstract), but was more recently presented This October (2006) at the 66th Annual meeting of the Society of Vertebrate Paleontology, in Ottawa, Canada (abstract can be downloaded here). Incidentally, the findings have implications for the famous cryptid sometimes regarded as a plesiosaur, the Loch Ness Monster – the inability to raise the neck out of the water contrasts with reports of Nessie, and so constitutes evidence against a plesiosaur identity for any monster living in the loch.
The plesiosaur neck may have been used for sifting through the sea bed for soft animals such as worms and soft small crustaceans. The idea is backed up by other recent findings – namely the discovery of fossil stomach contents in a plesiosaur containing sea-shells as reported here last year (see news entry). Although the idea is appealing, Dr Noe states (personal communication) that this is probably only part of the story concerning the function of the long neck in plesiosaurs.
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