Nests, eggs, and embryos: revealing reproductive behaviour and ontogeny of early dinosaurs

This project will cast new light on the early evolution of dinosaur reproductive behaviour, and the establishment of dinosaur-dominated faunas, by describing exceptional new fossils from the Triassic and Early Jurassic, a critically important time interval of dinosaur evolution.

The main focus will be dinosaur nests from the latest Triassic (c. 202 Ma) of Sweden and the earliest Jurassic (c. 200 Ma) of Poland. The Swedish site, the oldest known theropod nest site, consists of ‘mounds’ containing egg remains.

It is associated with the largest known resting trace of a theropod, probably left by an individual protecting the nest. The Polish site yields theropod eggs containing embryo bones.

At both sites I will examine nest architectures, clutch patterns, eggshell microstructures, and (where possible) embryo ontogeny, as well as the fossil records of the surrounding sediments.

Juvenile theropod bones from an older Polish locality (c. 230 Ma) will create a comparative context for analysing ontogenetic evolution.

The project will involve fieldwork, studies of museum collections, and collaborations with world-leading researchers in Edinburgh and Uppsala. Cutting-edge techniques such as synchrotron microtomography and 3D optical scanning will be used to study the material.

The results will illuminate the poorly known period when dinosaurs were making the transition from rare, small, low-diversity faunal components to faunally dominant and sometimes gigantic terrestrial vertebrates.