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For the first time, the fossil remains of a duck-billed dinosaur have been found in Africa. The discovery suggests that dinosaurs sometimes swam across wide oceans, and were more capable in water than we thought.

鈥淎s best we can tell, dinosaurs swam across ocean barriers,鈥� says Nicholas Longrich at the University of Bath in the UK.

Duck-billed dinosaurs, or hadrosaurs, were common towards the end of the dinosaur era. They were large animals that mostly ate plants. The bones in their snouts were flattened, giving them a duck-like appearance.

Hadrosaur fossils are common in North America and Eurasia, but hadn鈥檛 previously been found in Africa. This is explained by the positions of the continents at the time at which they lived. Europe and North America were part of one large continent called Laurasia, while a second large continent called Gondwana held what are now Africa and South America. Hadrosaurs were thought to live only on Laurasia.

Longrich and his colleagues obtained parts of the upper jaw of a 67-million-year-old hadrosaur from Morocco. It had been found in a phosphate mine. They have since donated the fossil to the Marrakech Museum of Natural History.

There is no evidence of a land bridge linking Laurasia and Gondwana, says Longrich. The most likely explanation is that hadrosaurs crossed open water, demonstrating a swimming ability also seen in some of today鈥檚 large mammals.

鈥淓lephants swim well and they get out to islands,鈥� says Longrich. Elephants lived on Mediterranean islands like Sicily until about 20,000 years ago.

狈辞飞补诲补测蝉,听dinosaurs are typically thought to have been strictly terrestrial. The only large dinosaur acknowledged to have spent a lot of time in water is the predator Spinosaurus.

Longrich says this might be because, decades ago, many palaeontologists thought dinosaurs would 鈥渉ang out in swamps鈥�, assuming they were too bulky to move on land. Later studies disproved this. 鈥淧eople realised that this hardcore aquatic dinosaur was a bunch of nonsense, and kind of overcorrected for that by saying all dinosaurs are terrestrial,鈥� he says.

鈥淒inosaurs are a diverse group,鈥� says Longrich. He points out that many animals that we think of as terrestrial are really semiaquatic, including polar bears and moose. The same may be true of some dinosaurs. 鈥淚t makes sense that some of them at least were playing with it a bit,鈥� he says.