Massospondylus nesting site – with fossilised eggs and tiny footprints – is 100m years older than any previously discovered

This article is more than 8 years old

This article is more than 8 years old

A dinosaur nesting site older than any discovered before suggests that the creatures were caring mothers early in their evolution.

Scientists uncovered clutches of fossilised eggs at the site in the Golden Gate Highlands national park, South Africa, many containing embryos. They also found footprints of hatchlings showing that young dinosaurs stayed in the nest long enough to double in size.

The nests belonged to Massospondylus, a six-metre (20ft) ancestor of long-necked "sauropod" dinosaurs that lived 190m years ago. The newly discovered nesting ground is 100m years older than any found before.

At least 10 nests were uncovered and each contained up to 34 round eggs in tightly clustered clutches. Their distribution indicates that dinosaurs returned repeatedly to the same spot to lay their eggs.

Their highly organised nature suggests the mothers may have arranged their eggs carefully after laying them, according to the research published in the journal Proceedings of the National Academy of Sciences.

"Even though the fossil record of dinosaurs is extensive, we actually have very little fossil information about their reproductive biology, particularly for early dinosaurs," said Dr David Evans, curator of vertebrate palaeontology at the Royal Ontario Museum in Canada.

"This amazing series of 190m-year-old nests gives us the first detailed look at dinosaur reproduction early in their evolutionary history, and documents the antiquity of nesting strategies that are only known much later in the dinosaur record."

The scientists believe many more nests at the site, now buried in rock, remain to be discovered.