One of the biggest questions in plesiosaur research concerns their most striking and obvious feature: why did their necks get so long? To determine how plesiosaurs used – or didn’t use – their long necks, we must understand their anatomy. Outline of Albertonectes, the plesiosaur with the most neck vertebrae. By Adam S. Smith. Contrary to early work (Zarnik 1925),...
How did plesiosaurs swim? There is no other animal with four large flippers like a plesiosaur. This has led to much debate about plesiosaur locomotion (Robinson 1975). The tail in plesiosaurs is short, so while it may have provided some assistance as a rudder, it was not used for propulsion. Plesiosaurs were paraxial swimmers – they used their limbs to...
What did plesiosaurs eat and how do we know? Types of evidence for diet Pollard (1990) established three broad categories of evidence for diet in prehistoric organisms: direct evidence, indirect evidence and general evidence. Direct evidence consists of various grades of gut contents, indirect evidence includes bite marks, and general evidence consists of functional analyses. Focussing specifically on the...
Introduction Plesiosaurs belong to a larger group of reptiles known collectively as the Sauropterygia. Sauropterygians had a worldwide distribution (Rieppel 1997) and range in age from the Triassic Period to the end of the Cretaceous Period (Benton 1990a). The fossil record of sauropyerygians is relatively rich because aquatic environments have high rates of deposition and so organisms that inhabit water...
All plesiosaurs have four flippers, a short body and a short tail. The skeleton below belongs to Meyerasaurus victor, one of the most complete plesiosaur specimens ever found. It shows the ventral surface (underside) of the animal (redrawn from Fraas 1910). Cranium and jaws There is considerable variation in plesiosaur skull anatomy. N.B. This section of the page is currently...
Some museum collections contain a few scraps of plesiosaur materal. Others have large quantities. Whatever the size of the collection, there are almost always odd specimens which are interesting in one way or another and usually encountered whilst engaged in some completely different project. We may make a mental note to come back to them, but usually either forget, or...