Paleontologists have found the fossilized remains of two Jurassic dinosaur species in Co. Antrim in Northern Ireland. These are the first dinosaur remains reported from anywhere in Ireland and some of the most westerly in Europe.
“This is a hugely significant discovery,” said Dr. Mike Simms, a curator and paleontologist in the Department of Natural Sciences at National Museums Northern Ireland.
“The great rarity of such fossils here is because most of Ireland’s rocks are the wrong age for dinosaurs, either too old or too young, making it nearly impossible to confirm dinosaurs existed on these shores.”
The two fossil bones were found by the late Roger Byrne, a schoolteacher and fossil collector, who donated them along with many other fossils to Ulster Museum.
“The fossils that Roger Byrne found were perhaps swept out to sea, alive or dead, sinking to the Jurassic seabed where they were buried and fossilized,” Dr. Simms said.
Originally it was assumed the fossils were from the same animal, but Dr. Simms and colleagues were surprised to discover that they were from two completely different dinosaurs.
One is part of a femur (upper leg bone) of a four-legged plant-eater called Scelidosaurus.
The other is part of the tibia (lower leg bone) of a two-legged meat-eater similar to Sarcosaurus.
Dr. Simms with the tibia of Sarcosaurus on the left and the femur of Scelidosaurus on the right. Image credit: National Museums Northern Ireland.
“Analyzing the shape and internal structure of the bones, we realized that they belonged to two very different animals,” said Dr. Robert Smyth, a paleontologist in the School of the Environment, Geography and Geological Sciences at the University of Portsmouth.
“One is very dense and robust, typical of an armored plant-eater.”
“The other is slender, with thin bone walls and characteristics found only in fast-moving two-legged predatory dinosaurs called theropods.”
“Despite being fragmentary, these fossils provide valuable insight on a very important period in dinosaur evolution, about 200 million years ago,” he added.
“It’s at this time that dinosaurs really start to dominate the world’s terrestrial ecosystems.”
“Scelidosaurus keeps on turning up in marine strata, and I am beginning to think that it may have been a coastal animal, perhaps even eating seaweed like marine iguanas do today,” said Professor David Martill, also from the School of the Environment, Geography and Geological Sciences at the University of Portsmouth.
The findings were published in the Proceedings of the Geologists’ Association.
Michael J. Simms et al. First dinosaur remains from Ireland. Proceedings of the Geologists’ Association, published online November 11, 2020; doi: 10.1016/j.pgeola.2020.06.005