‘Elgin Reptiles’: the origins of the modern terrestrial fauna

Dr Davide Foffa
Research Fellow 2018

Dr Davide Foffa
National Museum Scotland

The Triassic was a critical time for the evolution of life on Earth, with the first appearance of some of the most successful animals that ever lived, including lizards, dinosaurs, turtles and crocodilians, the descendants of which are still important components of today’s terrestrial ecosystems. Well-preserved fossils of the most primitive members of these groups are rare, their anatomy is still poorly understood, and thus the origins and early evolutions of these animals are still matters of debate.

Some of the most promising fossils that could fill these gaps are the ‘Elgin reptiles’ from the Late Triassic Lossiemouth Sandstone Formation of Northern Scotland. These animals are thought to be the closest relatives to modern reptile lineages, so learning their anatomy is essential to answering the questions: “Why are groups that first appeared 200+ million years ago still dominating terrestrial assemblages today, and how did they become so successful?”. However, the ‘Elgin reptile’ fossils are difficult to study because their unique preservation as cavities in the sandstone makes large parts of these specimens impossible to study with traditional methods. Cutting-edge X-ray CT scanning technology offers a solution to these issues, because it can resolve in great detail sand-grain size features hidden within the rocks, as shown by our preliminary tests. In this project, I will use microCT scanning techniques to create detailed 3D reconstructions of the skeletons of six key ‘Elgin reptiles’ species.

"Why are groups that first appeared 200+ million years ago still dominating terrestrial assemblages today, and how did they become so successful?"

These new and otherwise unachievable data will help to finally understand the anatomy of the earliest members of the lizard, turtle, dinosaur and crocodilian family trees, with a high potential of discovering new species. The following phases of this project will use these data to shed light on the origins and relationships of some of the most successful groups that ever lived, while describing the composition, structure and palaeoecology of one of the first modern-style terrestrial ecosystems.

This project is expected to produce significant scientific results on a hotly-debated and popular topic, durable high-quality materials for future works, and to attract significant public interest through improved displays and outreach activities at the host and collaborating institutions.