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Fish swam in fear

发布时间:2019-03-08 05:13:13来源:未知点击:

By Jeff Hecht in Boston BIG predatory dinosaurs came in even more shapes and sizes than palaeontologists thought. A newly discovered giant fish-eater from Africa named Suchomimus, or “crocodile mimic”, had a powerful jaw that measured 1 metre long but was only 10 centimetres wide. Suchomimus lived some 100 million years ago. “It was the most common predator at the time,” says Paul Sereno of the University of Chicago. Over 80 per cent of the fossils of predators his team has found at a site in Niger belong to the species. Tyrannosaurs and other well-known big predatory dinosaurs had huge skulls with wide jaws and preyed on land animals. Suchomimus was adapted to eating fish—although it probably took some terrestrial prey as well. With narrow, crocodile-like jaws and a long flexible neck it would have stalked in up to 2 metres of water. At about 11 metres long and weighing 4 tonnes, Suchomimus was close to Tyrannosaurus rex in size, but had broader shoulders and powerful forelimbs. Suchomimus belongs to a little-known group called the spinosaurs. The original specimen, Spinosaurus, which was discovered in Egypt, was destroyed in an Allied bombing raid on Munich during the Second World War. It is thought to have had a sail running right down its back. Suchomimus appears to have had a smaller, half-metre-long sail over its hips. Its closest known relative was Baryonyx, a smaller fish-eating dinosaur discovered in southern England, Sereno’s group reports in Science (vol 282, p 274). A third spinosaur is known from Brazil. No one had suspected that a spinosaur would have been the dominant predator in any ecosystem, however. Sereno suggests that this reflects palaeontologists’ limited knowledge of African dinosaurs. “This may be equivalent to finding the first tyrannosaur bones in 1905 in North America,