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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_____.
A.
fly
B.
fight
C.
keep warm
D.
frighten the enemy
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举一反三
【简答题】诗中能揭示主旨的诗句是 , 。
【多选题】下列各项中,列示在资产负债表“存货”项目中的有( )。
A.
委托代销商品
B.
受托加工物资
C.
委托加工物资
D.
发出商品
【单选题】下列哪项不属于推拿治疗原则( )
A.
整体观念,辩证施术
B.
标本同治,缓急兼顾
C.
以动为主,动静结合
D.
以静为主,动静结合
【单选题】由曲线 与 , , 所围成的平面图形的面积为  (   )
A.
B.
1
C.
D.
2
【单选题】当瘫痪时可产生“翼状肩”症状的肌是
A.
斜方肌
B.
胸小肌
C.
背阔肌
D.
前锯肌
E.
胸大肌
【判断题】茶叶 价格上升一般会导致 咖啡等茶替代品需求减少。
A.
正确
B.
错误
【单选题】以对被评估的机器设备进行模拟重置,按现行技术条件下的设计、工艺、材料、标准、价格和费用水平进行核算,这样求得的成本称为()。
A.
完全复原成本
B.
复原重置成本
C.
更新重置成本
D.
实际重置成本
【单选题】由曲线 与 轴所围成的平面图形的面积为( )
A.
1
B.
2
C.
【单选题】在联营银行中,任何一家外国投资者拥有的股权都只能保持在 ( ) 以下,只 拥 有少数股权,其余股权可以为东道国投资者所有,或由几家外国投资者共有 。
A.
50%
B.
30%
C.
40%
D.
60%
【判断题】word在进行查找和替换时,不能使用通配符
A.
正确
B.
错误
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