'Dinosaur disco' footprints reveal lifestyle of Jurassic giants: study

Washington: On a platform of rock jutting into the Atlantic on Scotland's Isle of Skye, hundreds of newly discovered dinosaur tracks are changing the way scientists view the lifestyle of some of the largest creatures ever to walk the Earth.

Scientists on Tuesday said they found the vast collection of Jurassic Period footprints, some reaching 28 inches in diameter, made when dinosaurs called sauropods waded through shallow water in a brackish lagoon 170 million years ago.

"There were clearly lots of sauropods moving all around this lagoon. They were at home there, they were thriving there. Looking at the chaotic jumble of tracks, it looks like a dance floor, like a dinosaur disco," University of Edinburgh paleontologist Steve Brusatte said.

Sauropods were four-legged plant-eaters with long necks, long tails, pillar-like legs and immense bodies. It is uncertain what species made the Isle of Skye tracks, but Brusatte estimates these dinosaurs were 50 feet long and weighed 15-20 tonnes.

Sauropods as a group included the planet's biggest terrestrial animals ever. The Isle of Skye sauropods were relatively primitive, perhaps "an early cousin or ancestor of the famous ones like Diplodocus and Brontosaurus," Brusatte said.

Brusatte said many decades ago scientists thought sauropods must have lived in swamps because such behemoths could never support their weight on land, but that idea was discarded in the 1970s with the realization they were well-adapted for living on land as shown by their skeletal structure.

This fossil footprint site and other recent finds show these dinosaurs really did spend at least some time in the water, Brusatte said. These sauropods were not swimmers or pure water-dwellers, probably living mostly on land but still spending considerable time in the water, he said.

"Maybe these lagoons were a ready source of food, or offered protection from predators. But regardless of the answer, this discovery and the other recent ones are inspiring us to re-imagine the lifestyles of these most incredible of ancient creatures," Brusatte said.

Few fossils are known from this age, the middle of the Jurassic, University of Edinburgh paleontologist Tom Challands said.

The site boasts at least three layers of sandstone and limestone with trackways, demonstrating sauropods flourished in lagoon environments over multiple generations. The main layer, with numerous trackways crisscrossing one another, measures about 50 by 80 feet.

The research was published in the Scottish Journal of Geology.