The first fossil dinosaur to be found with an intact body covering has feathers from head to tail. strengthening the view that m

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问题    The first fossil dinosaur to be found with an intact body covering has feathers from head to tail. strengthening the view that modern birds evolved from dinosaurs, scientists say in an article published in London Wednesday,
   The 130 million-year-old Dromaeosaur found in China provided the best evidence that some dinosaurs developed primitive feathers, not for flight but to keep warm, according to a report in the scientific journal Nature.
   The Dromaeosaurs were small, fast-running predators closely related to the Velociraptor which starred in the film Jurassic Park. Like Velociraptor, they had a sickle-like claw on the middle toe, sharp teeth, and a bone structure similar to that of modern birds.
   The fossil was unearthed early last year by farmers digging in north-eastern China’s Liaoning Province. where other feathered dinosaurs have been found.
   The Dromaeosanr’s skeleton was found between two slabs of fine grained rock, and resembles that of a large duck with a long tail and an oversized head. indicating that it was a young specimen.
   Its head and tail are covered with downy fibres, while other parts of the body sprout tufts or sprays of filaments resembling primitive feathers. The backs of the arms are adorned with branched structures similar to the barbs of a modem bird feather.
   Dr Mark Norell, from the American Museum of Natural History, New York, head of a U. S. team examining the find with Chinese researchers, said"This fossil radically modifies our vision of these extinct animals. It shows us that ad- vanced theropod(two-legged)dinosaurs may have looked more like weird birds than giant lizards. "
   Several new species of dinosaur with feather-like structures have been found in the Liaoning fossil beds since the first, Sinosauropteryx, was discovered in 1995. In most cases the fossils have been jumbled or incomplete, making it unclear how the featherlike structures related to the animal’s body.
   Most experts now believe that modern birds evolved from dinosaurs, and cite the Liaoning fossils as evidence. Critics of the theory have, however, argued that the feather-like structures are not the remains of primitive feathers, or that the specimens are mixed-up fossils of early birds and dinosaurs.
   The new find may help resolve the debate.
The main role of some dinosaurs’ developed primitive feathers is to_____.

选项 A、fly
B、fight
C、keep warm
D、frighten the enemy

答案C

解析 第二段讲到这些恐龙原始的羽毛不是用来搏斗,而是为了保暖。故选C。
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