Researchers have discovered the skin imprints of a dinosaur left behind just before the fatal asteroid wiped the creatures off the planet, making them some of the last pieces of evidence of dinosaurs from Europe. The two sections of impressions, thought to have been made by the same dinosaur, were discovered in northern Spain by scientists working at the Autonomous University of Barcelona.
The skin prints were preserved in the soft mud of a river bank, perhaps when the giant creature lay down, though without anything else to go on, it is impossible to tell if the dinosaur was simply taking a break, or if this was its final resting place. Either way, not long after that the bank must have been covered in a fine layer of sediment that sealed the impression in, before turning it into rock. By being able to accurately date the rock itself, the researchers can say without a doubt that the print was made approximately 66 million years ago – just before the infamous asteroid struck.
This makes it one of the last pieces of evidence of dinosaurs living in Europe before they were all rendered extinct. “This is the only registry of dinosaur skin from this period in all of Europe, and it corresponds to one of the most recent specimens, closer to the extinction event, in all of the world,” explains Victor Fondevilla, the lead author of the study published in Geological Magazine. “There are very few samples of fossilised skin registered, and the only sites with similar characteristics can be found in the United States and Asia.”
The imprint is incredibly distinctive, being made up of “pentagonal and hexagonal contours of the scales confer[ing] a rosette arrangement, [with] each scale being surrounded by five or six scales,” according to the authors. The size of the scales rules out the maker of the prints being either a carnivorous dinosaur or a hadrosaur, both of which were known to live in the region at the right time. But the discovery of some other dinosaur footprints from the same rock layer nearby may give a hint. These were formed by a titanosaur, suggesting that both skin and footprints may belong to the same or similar culprit.
The unique age of the sandstone, dating from just before the asteroid hit, is rare not only for Europe, but also in other parts of the world. This makes the discovery of the imprints an incredibly exciting and significant find.