A new fossil find in Brazil rewrites the history of the dinosaurs

HOW the dinosaurs died out after ruling the planet for over 150m years was a mystery that consumed palaeontologists throughout much of the 20th century. These days it is mostly accepted that they were done in by the climatic after-effects of the impact of a giant asteroid, specifically the one that carved a vast crater 180km across near the Yucatan Peninsula in Mexico. Now the focus has shifted from how they died out to where they came from in the first place. In a paper just published in Current Biology, a team led by Max Langer at the University of São Paulo reports the excavation of four fossils that shed some intriguing light on two different aspects of that question.

The fossils, found by Sergio Cabreira at the Lutheran University of Brazil, come from the Santa Maria formation in the south of the country. One of them, at 230m years in age, is one of the oldest dinosaur fossils ever found. Typically, such ancient finds are nothing more than bone fragments, but this specimen, named Buriolestes schultzi, is in remarkably good shape. It is a distant ancestor of the long-necked sauropods such as Diplodocus and Brachiosaurus. Those giant animals, which stood up to 16 metres high and weighed 50 tonnes or more, were vegetarians.