Sydney: A 190 million-year-old dinosaur nesting site the ‘oldest ever’ has been unearthed in South Africa.

The discovery of the prosauropod dinosaur Massospondylus has revealed significant clues about the evolution of complex reproductive behaviour in early dinosaurs.

Led by University of Toronto (Mississauga) palaeontologist Robert Reisz, with co-author Eric Roberts from James Cook University and a group of international researchers, the study describes clutches of eggs, many with embryos, as well as tiny dinosaur footprints.

According to the authors, the newly-unearthed dinosaur nesting ground is over 100 million years older than previously known nesting sites.

Roberts, senior lecturer of geology, said the sediments were an incredible source of information about the life and times of early dinosaurs."Clues recorded in the rock, such as the tracks of the hatchling dinosaurs, traces of ancient ripples and evidence desiccation cracks all suggest that these animals were nesting in a dynamic shoreline environment with fluctuating climate conditions," he said.

Roberts said over 10 nests had been discovered at several levels at the site, each with up to 34 round eggs in tightly clustered clutches.