The oldest African dinosaur, which lived about 230 million years ago, was discovered in Zimbabwe: called Mbiresaurus raathi, it was a relative of the sauropods characterized by a long neck.
About a meter tall, weighed less than 30 pounds, had a small head, serrated triangular teeth, and moved on two legs.
Its nearly complete fossil fills a geographical gap in the fossil record of the oldest dinosaurs, showing that their dispersal was conditioned by climatic factors.
This is indicated by the study published in Nature by an international group of paleontologists led by Virginia Tech.
The Mbiresaurus raathi fossil was found along with the remains of other Late Triassic animals, such as a herrerasauride dinosaur, ancient mammalian relatives such as the cynodon, armored reptiles such as aetosaurs, and rincosaurus reptiles.
Similar fossil deposits from the same era had already been found in South America and India.
"The oldest dinosaurs come from roughly the same ancient latitudes along the southern temperate climate belt that was about 50 degrees south," explains researcher Christopher Griffin.
Precisely for this reason, his team decided to conduct excavations in northern Zimbabwe, in the areas that fell within that ancient climate zone, thus bridging the gap between southern Brazil and India.
To test the hypothesis that the first dinosaurs were indeed confined by climatic constraints in the south of the ancient supercontinent Pangea, the researchers conducted a statistical study on the dinosaur evolutionary tree, thus discovering that their dispersion towards the north occurred at a period of high humidity on a global level (Carnian Rain Event) which broke the climatic 'barriers'.