Pick a random piece of plesiosaur paleoart and chances are the animal will be depicted with an arched back. A hump, almost. But did plesiosaurs really have the hump?
This arched posture can be traced back in the scientific literature to Andrews’ 1910-13 seminal works on the marine reptiles from the Oxford Clay.
One of the many areas of controversy in plesiosaur palaeobiology is the topic of how they swam. The question goes back almost 200 years to the 1820s when the first complete plesiosaurs were described from the Jurassic cliffs of Lyme Regis, UK.
It was once common knowledge that elasmosaurid plesiosaurs were bendy-necked beasts that swanned about near the surface, striking snake-like at slippery prey. It is now common knowledge that their necks were relatively rigid rod-like structures, the function of which remains something of a mystery.
An exciting new paper published this week in the journal Science (Vol. 333, p.870-873) provides the first direct evidence for live birth in plesiosaurs, and may have implications for plesiosaur behaviour (O’Keefe and Chiappe 2011).
So far, 2008 has seen a healthy number of new papers on plesiosaurs and a few new taxa too. Way back in February, Druckenmiller and Russell (2008a) introduced Nichollsia borealis, a plesiosaur of uncertain affinity, based on a beautifully preserved specimen from Alberta, Canada.
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 Noè of the University of Cambridge . After examining the neck vertebrae of the long-necked plesiosaur Muraenosaurus, whose name translates as ‘Moray eel lizard’, Dr Noè concluded that the natural position of the neck was a downwards curve towards the seabed.
