'sea serpent' is snake ancestor
Researchers claim the 'missing link' between lizards and snakes, in the evolutionary tree, is not, as previously thought, a tiny burrowing lizard but a giant marine monitor.
In the latest issue of Nature, researchers from the US, Australia and Canada have shown that the skulls of giant lizards called mosasaurs, that lived alongside the dinosaurs, were intermediate between lizard skulls and snake skulls.
"In particular, mosasaurs had highly flexible jaws just like those of snakes, for instance, the lower jaws can be dislocated to allow them to engulf extremely large prey" said one of the authors, Dr Michael Lee from the Department of Zoology, University of Queensland.
The ability of snakes to devour huge prey is one their most distinguishing features but the transition from the relatively inflexible lizard skull to the highly flexible snake skull had puzzled scientists for some time.
Mosasaurs were voracious predators with flippers and a paddle-like tail and grew to over 15 metres long. They retained the rigid upper jaw of lizards but had a highly flexible lower jaw.