为什么早期的恐龙幸存下来了，而鳄踝初龙却灭绝了？ 怀特塞德表示还没有找到原因。
Why the early dinosaurs survived while the crurotarsans perished is not known, said Whiteside.
初龙是鳄鱼、恐龙类以及和现代鸟类的始祖。这次的发现有助于解释2.5亿年前初龙在世界范围内大规模存在的原因。
The findings could help to explain why the archosaurs — the ancestors of crocodilians, dinosaurs, and modern birds — emerged to dominate the world some 250 million years ago.
在20世纪初，麦地那龙线虫病在非洲和亚洲许多国家广泛流行。
At the beginning of the 20th century, guinea-worm disease was widespread in many countries in Africa and Asia.
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