Scientists identified a new dinosaur species, Nyana rooiwalensis, which lived over 200 million years ago in South Africa. Even as a youngster, this creature weighed 400 kilograms. Researchers used X-rays and bone analysis to study the fossil. The authors noted, "adult Nyana may have reached multi-tonne body masses" as they grew.
It probably walked on two legs and weighed about 400 kilograms (880 pounds), despite still being a youngster. Meet Nyana rooiwalensis, a newly identified dinosaur species that lived more than 200 million years ago in what is now South Africa.
The prehistoric creature is described in a new paper published in the journal Royal Society Open Science and was identified from a near-complete skull and several other fossilized bones.
Nyana belonged to a group of dinosaurs called sauropodomorphs, which eventually gave rise to enormous, long-necked giants such as Brachiosaurus and Diplodocus.
What makes this discovery particularly interesting is that it dates back to the Late Triassic, a time when these early dinosaurs were evolving and diversifying. Fossilized skulls from sauropodomorphs of this age are relatively rare, particularly in southern Africa, where it was found.
And although the remains were incomplete, they still had plenty to tell the scientists who examined them.
A prehistoric puzzle
The starting point for researchers led by Atashni Moopen of South Africa's University of the Witwatersrand was to use powerful X-rays to create a detailed 3D model of the skull.
They then compared its features with those of other sauropodomorphs to place Nyana on the dinosaur family tree.
The research team also examined thin slices of limb bones under a microscope for clues about its age and growth. This revealed that Nyana was still growing rapidly when it died. In fact, the researchers believe it was at least in its third year of growth despite its already considerable size.
But what about its weight? The scientists estimated this by measuring the circumference of its thigh bone and comparing it with growth curves derived from related dinosaurs. And although Nyana was already a hefty size, it still had plenty of growing to do.
"Extrapolation of these growth curves suggests that adult Nyana may have reached multi-tonne body masses," wrote the study authors in their paper.
The bigger picture
But the discovery, as fascinating as it may be, isn't just about one dinosaur. The researchers believe it could also shed new light on how these early dinosaurs evolved and spread around the world.
"It provides critical new data on skull morphology in early-diverging massopodans [an early group of sauropodomorph dinosaurs] that will be of use to future phylogenetic studies, suggests a novel biogeographical link between southern Africa and North America and supports the adoption of rapid growth strategies early in sauropodomorph evolution."