Tracking monsters: Skye and Australia's Dino Stampede
New research has questioned the established view of what is regarded as the only known example of a dinosaur stampede. But one Scottish scientist says he is interested, but not convinced, by the latest theory.
In central Queensland, Australia, there is the Dinosaur Stampede National Monument.
The monument is a former quarry where, since the 1960s, as many as 4,000 dinosaur footprints have been uncovered.
In 1984, the tracks were identified by scientists as being the result of small creatures fleeing from a larger animal, possibly a predator similar to the Tyrannosaurus rex, about 95 million years ago.
"The story is an interesting one," says Dr Neil Clark, of University of Glasgow's Hunterian Museum and Art Gallery.
However, he adds: "I am afraid that I don't agree with the aquatic footprints."
Two years ago a BBC Two programme, Dino Stampede, examined the Australian site and interviewed Dr Clark as an expert on the subject.
The programme used evidence of dinosaur footprints found at Valtos on Skye - Scotland's Misty Isle - to help explain what happened in Queensland.
Dr Clark has previously described Skye as one of the world's most important palaeontology sites. Its standing is underlined by the number of finds from the Middle Jurassic, about 170 million years ago.
Evidence of dinosaurs and ancient large reptiles from other periods have also been found on the island. They include more than 100 marks left by a lizard called Isochirotherium - also known as the hand-beast - 270 million years ago.'Dogs walking'
Dr Clark has been intrigued by the new research challenging Australia's dinosaur stampede.
"Yes, the animals probably were running about in wet mud, perhaps a shallow stream to allow for the aligning of the bits of plant, as they suggest," says Dr Clark.
"However, they would not have been running at the same rate counter to the flow direction, as they are with the current if they were swimming.
"Long claw marks is not an indication of swimming tracks."
Dr Clark adds: "If you ever go to the beach and look at the marks left by dogs walking, or running, along the shoreline, you will see some very long drag marks of their claws in the sand.
"I think that they are dealing with a shoreline deposit - which would also explain the aligning of the plant material parallel to the shore - with dinosaurs running along it, mostly in one direction, but not exclusively."
Dr Clark admits to also having some doubts about a stampede of small dinosaurs being pursued by a large predator.
He says that some of the footprints show animals running towards the bigger beast. Dr Clark suggests the tracks may have been made over a number of hours, days or weeks in different layers of mud.
While having doubts about there having been a stampede, Dr Clark does not dismiss completely theories that the larger footprints were made by a theropod, a diverse group of creatures that stood up on their back legs and include Tyrannosaurus rex.
He said: "I would plank for the predator - or at least a large theropod of some sort - based on the sharp, pointed claw marks of the larger tracks."
The smaller prints may have been made by family groups of smaller theropods possibly similar to those that left footprints on Skye.
Dr Clark said: "In short, I am not sure that the case has been made for either the stampede, or the current swimming, and a lot more work will need to be done on this to account for all the observable features of the track site."