SA researchers help uncover new facts about dinosaur young

2012-01-24 07:27

Tiny footprints and fossil embryos at the oldest dinosaur nesting site have revealed new details about how they reared their young.

The nest belong to mid-sized dinosaurs from the Early Jurassic Period known as Massospondylus, which grew to four to six metres long as adults. Their eggs, however, are only six centimetres in diameter.

The traces left behind show that hatchlings stayed in the nest until they doubled in size, and that the young Massospondylus walked on four legs while young, but then likely stood upright on two legs as adults.

The analysis, led by South African and Canadian researchers, is based on findings at an excavation in the Golden Gate Highlands National Park in the Eastern Free State, and is published in the Proceedings of the National Academy of Sciences.

The fossils date to 190 million years ago, presenting the oldest known evidence of such behaviour among dinosaurs.

The first fossilised dinosaur embryo was in Golden Gate in 1976, and the first details about unhatched dinosaurs found inside fossilised eggs at the site were published to international fanfare in 2005.

At least 10 nests have now been uncovered at various levels, each holding as many as 34 eggs in close-knit clutches.

“The eggs, embryos, and nests come from the rocks of a nearly vertical road cut only 25 metres long,” said paleontologist Robert Reisz, a professor of biology at University of Toronto Mississauga.

“Even so, we found 10 nests, suggesting that there are a lot more in the cliff, still covered by tons of rock. We predict that many more nests will be eroded out in time as natural weathering processes continue.”

Researchers believe the layout of the nests suggest that the site was returned to repeatedly by the dinosaur mothers, who laid eggs together as a group and carefully organised their eggs in their nests.

“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 David Evans, associate curator, Vertebrate Palaeontology at the Royal Ontario Museum.

“This amazing series of 190 million 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.”

Join the conversation! encourages commentary submitted via MyNews24. Contributions of 200 words or more will be considered for publication.

We reserve editorial discretion to decide what will be published.
Read our comments policy for guidelines on contributions. publishes all comments posted on articles provided that they adhere to our Comments Policy. Should you wish to report a comment for editorial review, please do so by clicking the 'Report Comment' button to the right of each comment.

Comment on this story
Comments have been closed for this article.

Inside News24

Traffic Alerts
There are new stories on the homepage. Click here to see them.


Create Profile

Creating your profile will enable you to submit photos and stories to get published on News24.

Please provide a username for your profile page:

This username must be unique, cannot be edited and will be used in the URL to your profile page across the entire network.


Location Settings

News24 allows you to edit the display of certain components based on a location. If you wish to personalise the page based on your preferences, please select a location for each component and click "Submit" in order for the changes to take affect.

Facebook Sign-In

Hi News addict,

Join the News24 Community to be involved in breaking the news.

Log in with Facebook to comment and personalise news, weather and listings.