for National Geographic News
Around 160 million years ago, a small group of large meat-eating dinosaurs walked along the sandy shore of a lake on Scotland's Isle of Skye, leaving their footprints in the sand.
The tracks are the largest and the youngest dinosaur footprints ever found in Scotland. A research team headed by Neil Clark, a paleontologist at the University of Glasgow's Hunterian Museum, is at the site now, looking for more tracks and making molds of the 15 that have been uncovered.
The find is particularly significant because the tracks still lie in the rock strata in which they were formed.
"Tracks we've found before were all in loose boulders that had fallen down from the cliffs onto the beach," said Clark. "Finding them in their original horizon helps us define exactly how old they are."
Middle Jurassic Dinosaurs
Cathie Booth, a Skye resident, discovered the first track on a loose sandstone rock while walking her dog on the beach. Fourteen more tracks have since been found.
Each footprint shows three huge toes, with the middle toe the longest. Judging from the size of the tracks, some of which are close to 20 inches (50 centimeters) long, the dinosaurs walked on two feet and probably measured about 33 feet (10 meters) from head to tail. The toes are very narrow, suggesting that the animal was a carnivore. Plant eating dinosaurs generally have toes that are more spatulate (spread out).
Dinosaur remains from the lower end of the Middle Jurassicabout 167 to 160 million years agoare rare worldwide; there are only one or two places in the U.S. where remains of this age can be found, said Clark. He thinks the tracks may have been made by a Megalosaurus.
"It's impossible to be 100 percent sure unless we follow the traffic and find a dead dinosaur at the end," he said. "But the Megalosuarus was the only large meat-eating animal known at the time."
While today's Isle of Skye is cold and frequently battered by storms from the sea, 160 million years ago it was probably humid and swampy, said Clark.
Scotland's Jurassic Isle
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