Nearly 250 million years ago, a very odd reptile patrolled the shorelines and coves of the Triassic Alps. Called Tanystropheus, it had a toothy head and a body echoing that of modern monitor lizards. But between them stretched a horizontal, giraffe-like neck.

The question of how this 6m-long creature used that 2.7m-long neck has bedevilled paleontologists for more than 100 years, and it is seen as "one of the most baffling animals that ever lived", said Mr Stephan Spiekman, a paleontologist at the University of Zurich, in Switzerland.