Researchers have identified two sites on the Isle of Skye in Scotland which contain the handprints and footprints of various dinosaurs which lived around 170 million years ago during the Middle Jurassic Period.
Among these tracks are those which may have been left by plate-backed stegosaurian dinosaurs, which were not previously known in the region, according to study published in the journal PLOS ONE.
"This is the first record of stegosaurs from Scotland, and one of the oldest records in the world," Stephen Brusatte, an author of the study from the University of Edinburgh in Scotland, told Newsweek. "They tell us that these famous dinosaurs were evolving and spreading around by the middle part of the Jurassic Period, as part of a wave of dinosaur diversification."
Between them, the two coastal sites on the island—which lies to the west of the Scottish mainland—contain around 50 preserved dinosaur footprints.
Alongside the stegosaur prints, the sites also contain tracks of early carnivorous theropods—a group of bipedal, three-toed dinosaurs—as well as those of large herbivorous, ornithopod dinosaurs. The stegosaur tracks the team found are the oldest known, and those of the herbivorous ornithopod dinosaurs are also among the earliest evidence for this group of animals.
Dinosaur fossils and tracks from the Middle Jurassic—a time when major evolutionary diversification took place—are usually rare. However, the Isle of Skye is rich in both, providing a window into this region during a time when the environment would have looked totally different.
"Jurassic Scotland was a humid, subtropical paradise completely unlike the rainy Scotland of today," Brusatte said. "It was part of an island back then too, perched in the middle of the growing Atlantic ocean. Giant rivers drained mountains, emptying in the ocean, fringed by beaches and lagoons that were havens for many types of dinosaurs. The climate was probably similar to parts of Florida or Spain today."
The latest results indicate that the island hosted a thriving community of dinosaurs 170 million years ago, while also increasing the known diversity of dinosaurs that used to live there.
"These are important discoveries for Scotland, and expand the roster of dinosaurs that have been found here," Brusatte said. "We now know there was a great diversity of meat-eating and plant-eating dinosaurs, some big and some small, some with long necks and big guts, others like the stegosaurs with plates on their backs."
"Skye is one of the only places in the world with good fossils of Middle Jurassic dinosaurs, so these fossils are a window into one of the most important phases of dinosaur evolution—when species like stegosaurs and giant long-necked sauropods were diversifying like mad," he said.
